Semiconductor device having protection circuit

Abstract

The present invention relates to a semiconductor device having a protection circuit and, more specifically, to a semiconductor device having a protection circuit capable of preventing a failure of a device due to a reflected signal or an overvoltage signal by measuring the strength of a signal and adjusting the path of the signal and the strength of the signal on the basis of the measured strength.

Description

Semiconductor device with protection circuit

[0001] The present invention relates to a semiconductor device having a protection circuit, and more particularly, to a semiconductor device having a protection circuit capable of preventing a device from being damaged by a reflected signal or an overvoltage signal by measuring the intensity of a signal and controlling the path of the signal and the intensity of the signal based on the measured intensity.

[0002]

[0003] Systems that transmit and receive wireless signals, such as radar systems or communication systems, basically include many types of semiconductor devices, and semiconductor devices such as transmission and reception modules are formed through combinations of these semiconductor devices.

[0004] These semiconductor devices for wireless transmission and reception utilize dual RF signal paths for transmitting or receiving RF signals, and include a separate dual control device to perform path changes for RF signals, real-time status detection of the semiconductor device, and real-time control.

[0005] FIGS. 1 to 3 are examples of a conventional semiconductor device for wireless transmission and reception, which may be configured to include a hardware transmission and reception unit (A) connected to a data processing unit such as an FPGA, a switch, a drive amplifier (DRA), a high-power amplifier (HPA), a limiter (LMT), a low-noise amplifier (LNA), a circulator (CLR), and a wireless transmission and reception unit (B).

[0006] An antenna (ANT) for transmitting and receiving wireless signals may be connected to the wireless transceiver (B), and although not shown, the hardware transceiver (A) may include a control unit or core chip for controlling the transmission signal path and the reception signal path.

[0007] In these semiconductor devices for wireless transmission and reception, the transmission signal path and the reception signal path can be selected by controlling the switch and circulator (CLR) through the control circuit depending on whether the signal is being transmitted or received.

[0008] Here, the transmission signal path, as illustrated in FIG. 1, refers to a path in which a transmission signal (Output Signal) is transmitted sequentially from a hardware transceiver (A) through a switch (Switch), a driving amplifier (DRA), a high power amplifier (HPA), and a circulator (CLR) to a receiving terminal (B), and the reception signal path, as illustrated in FIG. 2, refers to a path in which a reception signal (Input Signal) is transmitted sequentially from a wireless transceiver (B) through a circulator (CLR), a limiter (LMT), a low noise amplifier (LNA), and a switch (Switch) to a hardware transceiver (A), and this path definition applies equally to the claims and the entire description of the invention relating to a semiconductor device having a protection circuit according to the present invention.

[0009] However, these conventional semiconductor devices have a problem in that, during the process of transmitting a transmission signal, the transmission signal may be reflected or input from the wireless transceiver due to mismatch between the semiconductor device and the antenna, a short circuit between the antenna and the receiver, or the antenna not being mounted, or signal reflection due to various reasons at a short distance, and the reflected signal may be input back into the circuit or element inside the semiconductor device.

[0010] At this time, a circulator included in a conventional semiconductor device prevented reflected signals from flowing into internal components, particularly high-power amplifiers. Specifically, the circulator is a passive, non-reciprocal element with a circular structure and three terminals, configured to output a signal input to one terminal to the terminal immediately adjacent to it. It only transmits signals in the forward direction and not in the reverse direction.

[0011] Therefore, if a reflected signal is generated for any reason and input to the circulator, the reflected signal is not transmitted to the high-power amplifier located in the transmission signal path, but is transmitted only to the reception signal path, thereby preventing the reflected signal from entering the high-power amplifier.

[0012] In other words, the reflected signal introduced into the receiving signal path by the circulator is transmitted to the limiter, and the limiter reduces the intensity of the reflected signal to be below the set voltage when it is above the limiter's limit level, so that the failure or damage to the internal components of the semiconductor device due to the introduction of the reflected signal can be prevented to some extent.

[0013] However, there is a limit to the method of limiting the intensity of the reflected signal using such a limiter, and on the other hand, due to the characteristics of the limiter, when the limit is exceeded, the exceeded reflected signal is reflected again from the limiter and flows into the circulator, as shown in Fig. 3.

[0014] In this case, depending on the characteristics of the circulator, an excessive reflection signal flows into the high power amplifier (HAP), which is the terminal right next to it, and a problem occurs in which this reflection signal damages the high power amplifier.

[0015] Therefore, this type of circuit configuration is not effective in preventing damage or failure of high-power amplifiers, and also has the problem that it does not fit with the recent trend of miniaturization and lightweight because the circulator applied to the circuit configuration for wireless transmission and reception is large, heavy, and expensive.

[0016]

[0017] The present invention is intended to solve the above-mentioned problem, and the purpose of the present invention is to provide a semiconductor device having a protection circuit capable of preventing a failure of an element due to a reflected signal or an overvoltage signal by measuring the intensity of a signal and controlling the path of the signal and the intensity of the signal based on the measured intensity.

[0018]

[0019] In order to achieve the object of the present invention, a semiconductor device having a protection circuit according to the present invention comprises a transmitting signal processing stage, a receiving signal processing stage and a wireless transmitting / receiving stage, a signal detection unit connected to the wireless transmitting / receiving stage and detecting the intensity of a signal transmitted from the wireless transmitting / receiving stage toward the receiving signal processing stage, a first switch connected to the signal detection unit and operated based on the intensity of the signal detected by the signal detection unit, a first resistive termination unit and a signal connection line electrically connected to the first switch so that a signal can be transmitted by the operation of the first switch, but is arranged logically in parallel so that signals can be transmitted alternatively from each other, and a control unit that controls the first switch based on the intensity of the signal detected by the signal detection unit, wherein the control unit operates the first switch so that a signal is transmitted to the signal connection line when the intensity of the signal detected by the signal detection unit is within a preset value, and operates the first resistive termination unit when the intensity of the signal detected by the signal detection unit exceeds a preset value. It is characterized by operating the first switch so that a signal is transmitted to the terminal.

[0020] Here, the semiconductor device having the protection circuit further includes a second switch connected to an opposite end of the signal connection line to which the first switch is connected, and the control unit controls the first switch so that the signal is transmitted through the signal connection line when transmitting or receiving a signal, and operates the second switch so that the transmission signal processing end and the signal connection line are connected when transmitting a signal and the signal can be transmitted, and operates the second switch so that the reception signal processing end and the signal connection line are connected when receiving a signal and the signal can be transmitted.

[0021] In addition, the semiconductor device having the protection circuit further includes a second resistive termination section that is arranged logically in parallel with the transmission signal processing section and the reception signal processing section and can be electrically connected to the signal connection line by the second switch, and the control section can cause the second switch to be connected to the reception signal processing section when the intensity of the signal detected by the signal detection section is within a preset value, and cause the second switch to be connected to the second resistive termination section when the intensity of the signal detected by the signal detection section exceeds the preset value.

[0022] In addition, the semiconductor device having the protection circuit further includes a switch protection unit arranged in parallel with the first switch so that an electrical branch point is formed between the first switch and the signal detection unit, and a signal can be separated and transmitted at the branch point, and a signal transmitted from the signal detection unit to the first switch is branched at the branch point and input to the switch protection unit, and the switch protection unit provides an impedance value that varies according to the intensity of the input signal, so that the intensity of the signal transmitted to the first switch can be adjusted.

[0023] In addition, the switch protection unit may include a response voltage generation unit that receives the intensity of a signal detected by the signal detection unit and generates a response voltage corresponding to the intensity of the input signal, and an impedance variation unit that provides an impedance value that varies according to the response voltage.

[0024] In addition, the impedance variation unit includes at least one transistor having one end connected to the branch point and an impedance element connected between the at least one transistor and ground, and the impedance value of the at least one transistor can be varied by the corresponding voltage.

[0025] Additionally, the impedance fluctuation unit may further include a voltage limiter connected between the branch point and the at least one transistor.

[0026]

[0027] According to the present invention, it is possible to prevent a device from being damaged by a reflected signal or an overvoltage signal by measuring the intensity of a signal and controlling the path of the signal and the intensity of the signal based on the measured intensity.

[0028] In addition, the effect of preventing device failure can be further increased by sequentially arranging resistive elements and controlling the signal path.

[0029] In addition, by adopting a switch protection unit, it is possible to prevent the switch itself from malfunctioning due to a reflected signal or overvoltage signal.

[0030] In addition, the switch protection unit can prevent switch failure while transmitting a signal to the switch by providing variable impedance including an impedance variation unit.

[0031] In addition, by employing a voltage limiter in the switch protection unit, the impedance value increases when the voltage is low, effectively preventing current from flowing to the switch protection unit, and the impedance value decreases when the voltage is high, allowing current to flow, thereby protecting the switch, thereby increasing power efficiency and preventing power waste.

[0032]

[0033] Figures 1 to 3 are configuration diagrams of conventional semiconductor devices.

[0034] Figure 4 is a configuration diagram of a semiconductor device having a protection circuit according to an embodiment of the present invention.

[0035] Fig. 5 is a configuration diagram of a semiconductor device having a protection circuit as shown in Fig. 4 during transmission.

[0036] Fig. 6 is a configuration diagram of a semiconductor device having a protection circuit as shown in Fig. 4 at the time of reception.

[0037] FIG. 7 is a configuration diagram showing the operation of the first switch when the signal intensity detected by the signal detection unit in the semiconductor device having the protection circuit illustrated in FIG. 4 exceeds a preset value.

[0038] FIG. 8 is a schematic diagram showing another embodiment of a second switch in a semiconductor device having the protection circuit illustrated in FIG. 4.

[0039] FIG. 9 is a configuration diagram showing the operation of the second switch when the signal intensity detected by the signal detection unit in the semiconductor device having the protection circuit illustrated in FIG. 8 exceeds a preset value.

[0040] Fig. 10 is a configuration diagram of a semiconductor device having a protection circuit as shown in Fig. 8, in which a switch protection unit is employed.

[0041] Figures 11 and 12 are configuration diagrams of a switch protection unit of a semiconductor device having the protection circuit illustrated in Figure 10.

[0042] Figures 13 and 14 are configuration diagrams of a voltage limiter of a semiconductor device having the protection circuit illustrated in Figure 12.

[0043]

[0044] The features and effects of the present invention described above will become more apparent through the following detailed description with reference to the accompanying drawings, so that those skilled in the art can easily practice the technical idea of ​​the present invention. The present invention can be modified in various ways and can take many forms, and specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, but should be understood to include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention. The terminology used in this application is only for the purpose of describing specific embodiments and is not intended to limit the present invention.

[0045] Hereinafter, the configuration, effects and preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0046] The present invention relates to a semiconductor device having a protection circuit capable of protecting a circuit from a reflected signal or an overvoltage signal as described above. To this end, a semiconductor device having a protection circuit according to an embodiment of the present invention includes, as illustrated in FIG. 4, a transmission signal processing unit (110), a reception signal processing unit (120), a wireless transceiver unit (130), a signal detection unit (140), a first switch (150), a signal connection line (160), a first resistive termination unit (170), and a second switch (180), and may further include, as illustrated in FIGS. 8 to 10, a second resistive termination unit (190), a branch point (J), and a switch protection unit (200).

[0047] Here, the transmission signal processing unit (110) is a configuration for processing a signal to be transmitted, and may include a driving amplifier and a high-power amplifier connected to the hardware transmission / reception unit as described above, but is not limited thereto.

[0048] This transmission signal processing unit modulates or amplifies signals generated from mobile phones, control units, MCUs, FPGAs, hardware, etc. to enable wireless communication, and can be formed by combining various components for this purpose.

[0049] The receiving signal processing unit (120) is a component that processes the received signal, and may be composed of a limiter, a low-noise amplifier, etc. as described above, but is not limited thereto.

[0050] This reception signal processing unit (120) also plays a role in demodulating, removing noise, or amplifying a signal received as a wireless signal so that it can be utilized in a mobile phone, control unit body, M-chip, FPGA, hardware, etc., and various elements for this purpose can be combined and formed.

[0051] The wireless transceiver (130) is a configuration for transmitting and receiving wireless signals, and can be connected to an antenna (not shown), and other configurations not mentioned between the antenna and the semiconductor device having the protection circuit according to the embodiment of the present invention can be included, but it is arranged to be closest to the antenna and to be able to exchange signals with the antenna through the wireless transceiver (130).

[0052] This wireless transmitter / receiver (130) receives a wireless signal through an antenna and transmits it toward a reception signal processing unit (120).

[0053] The signal detection unit (140) is connected to the wireless transmission / reception unit (130) and detects the intensity of the signal transmitted from the wireless transmission / reception unit (130) toward the reception signal processing unit (120).

[0054] Here, the signal transmitted toward the receiving signal processing unit (120) may be a normal signal received through the antenna in a normal situation, but may also be a reflected signal or an abnormal signal.

[0055] Here, an abnormal signal refers to an abnormal signal such as a signal with a high voltage momentarily transmitted through an antenna.

[0056] Meanwhile, a reflected signal refers to a signal that is reflected and returned instead of being transmitted to the outside due to misalignment with the antenna, a short circuit between the wireless transceiver (130) and the antenna, or the antenna not being mounted when transmitting a signal from a semiconductor device such as the present invention, and refers to a signal that travels in the reception direction opposite to the direction of the transmission signal from the wireless transceiver (130) and returns toward the first switch (150) from the wireless transceiver (130).

[0057] The signal detection unit (140) detects the intensity of a signal transmitted from the wireless transceiver (130) toward the first switch (150), regardless of its type. To this end, the signal detection unit (140) may be configured to include, but is not limited to, a coupler, which is an RF passive element that distributes or combines signal power.

[0058] The intensity of the signal detected by the signal detection unit (140) is transmitted to the control unit (not shown), and the control unit operates the first switch (150) and the second switch (180) based on the intensity of the reflected signal, which will be described later.

[0059] The first switch (150) is electrically connected to the signal detection unit (140) and is operated based on the intensity of the signal detected by the signal detection unit (140).

[0060] Strictly speaking, as described above, the control unit receives the intensity of the signal detected by the signal detection unit (140) and, based on this, determines which component among the first resistive termination unit (170) and the signal connection line (160) the first switch (150) will transmit the signal to, thereby operating the first switch (150).

[0061] The signal connection line (160) and the first resistive termination (170) are electrically connected to the first switch (150) so that a signal can be transmitted selectively by the operation of the first switch (150).

[0062] The signal connection line (160) and the first resistive termination unit (170) are logically arranged in parallel, and the first switch (150) is provided so that the control unit can transmit a signal to either the signal connection line (160) or the first resistive termination unit (170).

[0063] Here, the signal connection line (160) transmits a signal transmitted from the first switch (150) connected to one side to the second switch (180) connected to the other side when the first switch (150) is operated to transmit a signal to the signal connection line (160).

[0064] Meanwhile, the first resistive termination (170) can perform a function of absorbing and extinguishing a signal transmitted through the first switch (150) when the first switch (150) is operated to transmit a signal to the first resistive termination (170), and as an example, the first resistive termination (170) can be grounded.

[0065] The second switch (180) is connected to the opposite end of the signal connection line (160) to which the first switch (150) is connected, i.e., the other side.

[0066] The second switch (180) is also operated by the control unit. When a signal is to be transmitted, as shown in FIG. 5, the control unit controls the first switch (150) so that the signal can be transmitted through the signal connection line (160), and at the same time operates the second switch (180) so that the transmission signal processing unit (110) and the signal connection line (160) can be connected to transmit the signal.

[0067] Meanwhile, when a signal is to be received, as shown in Fig. 6, the control unit controls the first switch (150) so that the signal can be transmitted through the signal connection line (160), and at the same time, the second switch (180) is operated so that the reception signal processing unit (120) and the signal connection line (160) can be connected to transmit the signal.

[0068] Based on this configuration, we will now first explain a first embodiment of an algorithm for protecting a semiconductor device having a protection circuit according to the present invention.

[0069] The control unit operates the first switch (150) so that the signal transmitted from the wireless transceiver (130) is transmitted to the signal connection line (160) as shown in FIG. 7, when the intensity of the signal detected by the signal detection unit (140) described above is within a preset value.

[0070] In other words, if the intensity of the signal detected by the signal detection unit (140) is a voltage or current value that does not damage the components, it is determined to be a normal signal, and the first switch (150) is controlled so that the signal passes through a normal reception signal path.

[0071] Meanwhile, the control unit operates the first switch (150) so that the signal is transmitted to the first resistive termination unit (170) when the intensity of the signal detected by the signal detection unit (140) exceeds a preset value.

[0072] That is, if the intensity of the signal detected by the signal detection unit (140) is a voltage or current value that may damage the elements (if it exceeds a preset value), it is determined to be an abnormal signal or a reflected signal, and the signal is prevented from passing through the receiving signal path, while at the same time, the signal is transmitted to the first resistive termination unit (170), thereby absorbing and extinguishing the signal having excessive intensity.

[0073] A semiconductor device having a protection circuit according to the present invention using this algorithm can prevent damage to a high-power amplifier, etc. in a receiving signal processing unit (120) due to a reflected signal.

[0074] Meanwhile, a second embodiment of an algorithm for protecting a semiconductor device having a protection circuit according to the present invention will be described below.

[0075] The semiconductor device having a protection circuit according to the present invention has a second resistive termination portion (190), which is an additional path configuration that can be selected by the second switch (180), as described above.

[0076] This second resistive termination section (190) is electrically connected to the second switch (180), as shown in FIG. 8, and is logically arranged in parallel with the transmission signal processing section (110) and the reception signal processing section (120).

[0077] The second resistive termination (190) can perform the function of absorbing and extinguishing a signal transmitted through the second switch (180) like the first resistive termination (170), and as an example, the second resistive termination (190) can be grounded.

[0078] The signal transmitted through the first switch (150) and the signal connection line (160) is configured to be transmitted to either the receiving signal processing unit (120), the transmitting signal processing unit (110), or the second resistive termination unit (190) depending on the operation of the second switch (180).

[0079] Here, a second embodiment of an algorithm for protecting a semiconductor device having a protection circuit according to the present invention is implemented, specifically as follows.

[0080] The control unit operates the second switch (180) so that the signal transmitted from the signal connection line (160) is transmitted to the receiving signal processing unit (120) when the intensity of the signal detected by the signal detection unit (140) described above is within a preset value, as shown in FIG. 8.

[0081] In other words, if the intensity of the signal detected by the signal detection unit (140) is a voltage or current value that does not damage the components, it is judged to be a normal signal, and the second switch (180) is controlled so that the signal passes through a normal reception signal path.

[0082] Meanwhile, when the intensity of the signal detected by the signal detection unit (140) exceeds a preset value, the control unit operates the second switch (180) so that the signal is transmitted to the second resistive termination unit (190), as shown in FIG. 9.

[0083] That is, if the intensity of the signal detected by the signal detection unit (140) is a voltage or current value that may damage the elements (if it exceeds a preset value), it is judged as an abnormal signal or a reflected signal, and the signal is prevented from passing through the receiving signal path, while at the same time, the signal is transmitted to the second resistive termination unit (190), thereby absorbing and extinguishing the signal having excessive intensity.

[0084] A semiconductor device having a protection circuit according to the present invention using this algorithm can prevent damage to a high-power amplifier, etc. in a receiving signal processing unit (120) due to a reflected signal.

[0085] Here, in terms of the effect of this configuration, as discussed in the first embodiment above, damage caused by reflected signals can be prevented to some extent by the configuration of the first switch (150) and the first resistive termination (170).

[0086] However, a high intensity signal may be transmitted to the signal connection line (160) for a very short time due to an operation delay or breakdown of the first switch (150), and in such a case, the elements in the transmission signal processing unit (110) may be damaged, so a double protection circuit is configured.

[0087] Therefore, for example, if the shielding rate of a signal or reflected signal exceeding a preset value in intensity by the first switch (150) and the first resistive termination (170) is 90%, and the shielding rate of a signal or reflected signal exceeding a preset value in intensity by the second switch (180) and the second resistive termination (190) is 90%, in Example 1, the probability of damage to the transmission signal processing unit (110) due to a reflected signal or the like is 10%, but in Example 2, since it is configured in a double manner, the probability of damage to the transmission signal processing unit (110) due to a reflected signal or the like is 0.1*0.1=0.01, that is, 1%, so it can be said that there is virtually no possibility of damage to the reception signal processing unit (120) due to a reflected signal.

[0088] Next, a semiconductor device having a protection circuit according to the present invention may further include a branch point (J) and a switch protection unit (200) in addition to the above configuration.

[0089] A branch point (J) is formed between the first switch (150) and the signal detection unit (140), and serves to electrically branch the signal. This branch point (J) may not be a physical element, and may include a contact formed to separate the signal along the signal transmission path.

[0090] The switch protection unit (200) is provided so that a signal separated from the branch point (J) can be transmitted, as shown in FIG. 10, and for this purpose, it is arranged logically in parallel with the first switch (150).

[0091] Accordingly, the signal transmitted from the wireless transmitter / receiver (130) to the signal detection unit (140) is branched at the branch point (J), and some of the signal is transmitted to the first switch (150) and the remainder is transmitted to the switch protection unit (200).

[0092] The switch protection unit (200) is provided to protect the first switch (150), and when the path of the reflected signal is considered, since the second switch (180) is located in series at the rear end of the first switch (150), if the first switch (150) is protected, the second switch (180) can naturally also be protected.

[0093] Before explaining the configuration of the switch protection unit (200), the characteristics of the first switch (150) and the second switch (180) used in the semiconductor device having the protection circuit according to the present invention will first be explained.

[0094] RF switches such as the first switch (150) and the second switch (180) used in a semiconductor device used for wireless transmission and reception like the present invention are elements commonly used in communication modules, and perform the role of passing an RF signal or bypassing the RF signal to ground (the first resistive termination in the present invention).

[0095] RF switches are also used to change the operating frequency of the antenna. RF switches are connected between the antenna and the impedance element, and also switch the connection of the impedance element to the antenna.

[0096] These RF switches require high voltage withstand characteristics, allowing them to withstand high RF signal power. When the RF switch is off, high voltages are applied, which can disrupt RF linearity and lead to physical damage.

[0097] Since the voltage that a switch in the off state can withstand is limited, it is important to prevent breakdown of the RF switch. In general, to prevent breakdown of the RF switch, a method of connecting multiple transistors in series is often used for RF switches.

[0098] When multiple transistors are used in series to form an RF switch, the voltage distributed to each transistor is lowered, which prevents breakdown of the RF switch.

[0099] However, since the breakdown of the RF switch occurs when the voltage is distributed high only to a specific stage among the transistors of several stages, a method of connecting more and more transistors in series is used to solve this problem. However, this method, when connecting an excessive number of transistors in series, has the problem that the on-state characteristics of the switch deteriorate.

[0100] Meanwhile, to compensate for this, a method of increasing the total width of the transistor is also used, but this method has the problem of causing the size of the integrated circuit to become excessively large.

[0101] Therefore, in the present invention, a signal is branched through a branch point (J), and the first switch (150) and the switch protection unit (200) are logically arranged in parallel.

[0102] Therefore, when a signal of an intensity exceeding a preset value is transmitted, i.e., a high voltage is applied, the first switch (150) is protected by preventing the high intensity signal from being directly and completely transmitted to the first switch (150) by being branched at the branch point (J).

[0103] Meanwhile, in the case where a normal signal, i.e. a signal with an intensity within a preset value, is transmitted, as will be described later, an impedance fluctuation unit (220) and a voltage limiter (240) are employed to prevent the signal from being transmitted to the switch protection unit (200), thereby preventing the signal reception efficiency from being reduced.

[0104] Below, the configuration of this switch protection unit (200) is described in detail.

[0105] The switch protection unit (200), as illustrated in FIG. 11, includes a corresponding voltage generation unit (210), a buffer (215), an impedance variation unit (220), and an impedance element (230), and may further include a voltage limiter (240).

[0106] The response voltage generation unit (210) receives a signal intensity information signal of a signal detected by the signal detection unit (140) and generates a response voltage corresponding to the intensity of the input signal.

[0107] The corresponding voltage generation unit (210) outputs the generated corresponding voltage to the buffer (215), and the buffer (215) drives the impedance variation unit (220) according to the corresponding voltage.

[0108] The impedance variation unit (220) varies the internal impedance value according to the output of the buffer (215), and therefore, logically speaking, the impedance variation unit (220) can be seen as providing an impedance value that varies according to the corresponding voltage.

[0109] In detail, the impedance variation unit (220) lowers the internal impedance value when the corresponding voltage increases (i.e., rises). Therefore, according to the voltage-current distribution law, a high-voltage signal (a signal having a strength exceeding a preset value) mostly flows toward the switch protection unit (200) with a low impedance value, thereby protecting the first switch (150).

[0110] Meanwhile, the impedance fluctuation unit (220) increases the internal impedance value when the corresponding voltage decreases (i.e., drops). Therefore, according to the voltage-current distribution law, normal signals (signals with a strength within a preset value) rarely flow toward the switch protection unit (200) with a high impedance value, and most of them are transmitted to the first switch (150), thereby preventing the reception efficiency of the signal from deteriorating when it is a normal signal.

[0111] The impedance variation unit (220) includes at least one transistor (T1 to Tn) that is connected in series with each other, as illustrated in FIG. 11. Here, in FIG. 11, the transistor is expressed as including a plurality of transistors, but is not limited thereto, and may be configured to include only at least one transistor.

[0112] A plurality of transistors (T1 to Tn) each receive the output of the buffer (215) through a gate resistor (Rg). In addition, the drain of the transistor (T1) is connected to the branch point (J), the drain of the transistor (T2) is connected to the source of the transistor (T1), and by the same logic, the drain of each transistor (Tn) can be connected to the source of the transistor (Tn-1). Meanwhile, the source of the transistor (Tn) is connected to the impedance element (230).

[0113] Each of these transistors (T1 to Tn) may be a FET (Field Effect Transistor), MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or BJT (Bipolar Junction Transistor), but is not limited thereto and any element that produces the same effect may be applied without limitation.

[0114] An impedance element (230) is provided between the impedance variation unit (220) and the ground. That is, the impedance element (230) is connected between the source of the transistor (Tn) and the ground.

[0115] The impedance element (230) includes at least one of a resistor, a capacitor, and an inductor, and provides a predetermined impedance value depending on the frequency of the RF signal.

[0116] Meanwhile, the switch protection unit (200) may further include a voltage limiter (240) connected between the branch point (J) and the impedance fluctuation unit (220), as illustrated in FIG. 12.

[0117] The voltage limiter (240) may be implemented using at least one diode. Alternatively, the voltage limiter (240) may include multiple diodes connected in series, as illustrated in FIG. 13 . Although FIG. 13 illustrates the configuration using multiple diodes, the present invention is not limited thereto and may be implemented using a single diode.

[0118] Meanwhile, since the RF signal is an alternating current, the voltage limiter (240) may include a first diode (241) and a second diode (242) connected back-to-back, as illustrated in FIG. 14.

[0119] The first diode (241) may include a plurality of diodes that are connected in series with each other, and the second diode (242) may include a plurality of diodes that are connected in series with each other and in the opposite direction to the first diode (241).

[0120] That is, the first diode (241) and the second diode (242) can be connected back-to-back. Accordingly, when the RF signal is a positive (+) value, the first diode (241) can operate as a voltage limiter, and when the RF signal is a negative (-) value, the second diode (242) can operate as a voltage limiter.

[0121] Meanwhile, of course, in FIGS. 13 and 14, the first diode (241) and the second diode (242) are expressed as including multiple diodes, but they can be implemented with only one diode.

[0122] By connecting this voltage limiter (240) between the branch point (J) and the impedance fluctuation unit (220), the efficiency of the switch protection unit (200) according to the present invention can be increased.

[0123] To explain this, the voltage limiter (240) is characterized by a characteristic in which, when a threshold voltage or higher is applied to both ends, when the voltage limiter (240) is turned on, a predetermined limiter voltage is applied to both ends.

[0124] That is, the voltage limiter (240) has a low impedance value above the threshold voltage. Meanwhile, by the same principle, the voltage limiter (240) is turned off and has a high impedance value below the threshold voltage.

[0125] When this is applied to the operation of the switch protection unit (200) according to the present invention, when a signal with an intensity exceeding a preset value is transmitted, the voltage limiter (240) is turned on, so that the voltage limiter (240) has a low impedance value, and therefore, according to the voltage-current distribution law, a high voltage signal (a signal with an intensity exceeding a preset value) mostly flows toward the switch protection unit (200) with a low impedance value, thereby protecting the first switch (150).

[0126] Meanwhile, when a signal with an intensity within a preset value is transmitted, the voltage limiter (240) is turned off, so that the voltage limiter (240) has a high impedance value. Therefore, according to the voltage-current distribution law, a normal signal (a signal with an intensity within a preset value) hardly flows toward the switch protection unit (200) with a high impedance value, and most of it is transmitted to the first switch (150), so that the reception efficiency of the signal can be prevented from being lowered when it is a normal signal.

[0127] The present invention has been described in terms of embodiments, and due to the above configuration, a semiconductor device having a protection circuit according to the present invention can protect not only the internal configuration including the reception signal processing unit (120), but also the first switch (150) and the second switch (180) due to reflected signals, etc.

[0128] The semiconductor device having a protection circuit according to an embodiment of the present invention has been described above. By employing the semiconductor device having a protection circuit according to the present invention, a user can measure the intensity of a signal, and control the path of the signal and the intensity of the signal based on the measured intensity, thereby preventing the occurrence of a failure of an element due to a reflected signal or an overvoltage signal.

[0129] In addition, the effect of preventing device failure can be further increased by sequentially arranging resistive elements and controlling the signal path.

[0130] In addition, by adopting a switch protection unit, it is possible to prevent the switch itself from malfunctioning due to a reflected signal or overvoltage signal.

[0131] In addition, the switch protection unit can prevent switch failure while transmitting a signal to the switch by providing variable impedance including an impedance variation unit.

[0132] In addition, by employing a voltage limiter in the switch protection unit, the impedance value increases when the voltage is low, effectively preventing current from flowing to the switch protection unit, and the impedance value decreases when the voltage is high, allowing current to flow, thereby protecting the switch, thereby increasing power efficiency and preventing power waste.

[0133] Above, a semiconductor device having a protection circuit according to each embodiment of the present invention has been described, and although the detailed description of the present invention described above has been described with reference to preferred embodiments of the present invention, it will be understood by those skilled in the art or having ordinary knowledge in the art that various modifications and changes can be made to the present invention within a scope that does not depart from the spirit and technical scope of the present invention described in the claims of the present invention.

Claims

1. Transmission signal processing unit, reception signal processing unit and wireless transmission / reception unit; A signal detection unit connected to the wireless transceiver and detecting the strength of a signal transmitted from the wireless transceiver toward the reception signal processing unit; A first switch connected to the signal detection unit and operated based on the intensity of a signal detected by the signal detection unit; A first resistive termination and a signal connection line electrically connected to the first switch so that a signal can be transmitted by the operation of the first switch, but arranged logically in parallel so that signals can be transmitted alternatively from each other; and It includes a control unit that controls the first switch based on the intensity of the signal detected by the signal detection unit; The above control unit, A semiconductor device having a protection circuit characterized in that when the intensity of a signal detected by the signal detection unit is within a preset value, the first switch is operated so that a signal is transmitted to the signal connection line, and when the intensity of a signal detected by the signal detection unit exceeds the preset value, the first switch is operated so that a signal is transmitted to the first resistive termination.

2. In paragraph 1, A semiconductor device having the above protection circuit, Further comprising a second switch connected to the opposite end of the end to which the first switch of the signal connection line is connected, The above control unit, Controlling the first switch so that the signal is transmitted through the signal connection line when transmitting or receiving a signal; When transmitting a signal, the second switch is operated so that the transmitting signal processing unit and the signal connection line are connected to transmit a signal. A semiconductor device having a protection circuit characterized in that, when a signal is received, the second switch is operated so that the reception signal processing unit and the signal connection line are connected to transmit a signal.

3. In paragraph 2, A semiconductor device having the above protection circuit, It further includes a second resistive termination section that is arranged logically in parallel with the above-mentioned transmitting signal processing section and receiving signal processing section and can be electrically connected to the signal connection line by the second switch. The above control unit, A semiconductor device having a protection circuit characterized in that when the intensity of a signal detected by the signal detection unit is within a preset value, the second switch is operated so that the signal is transmitted to the receiving signal processing unit, and when the intensity of a signal detected by the signal detection unit exceeds the preset value, the second switch is operated so that the signal is transmitted to the second resistive termination unit.

4. In paragraph 1, A semiconductor device having the above protection circuit, An electrical branch point is formed between the first switch and the signal detection unit, and a switch protection unit is further included that is arranged in parallel with the first switch so that a signal can be separated and transmitted at the branch point. A semiconductor device having a protection circuit, characterized in that a signal transmitted from the signal detection unit to the first switch is branched at the branch point and input to the switch protection unit, and the switch protection unit provides an impedance value that changes according to the intensity of the input signal, thereby controlling the intensity of the signal transmitted to the first switch.

5. In paragraph 4, The above switch protection part, A response voltage generation unit that receives the intensity of a signal detected by the signal detection unit and generates a response voltage corresponding to the intensity of the input signal; and A semiconductor device having a protection circuit, characterized by including an impedance variation unit that provides an impedance value that varies according to the corresponding voltage.

6. In paragraph 5, The above impedance fluctuation part is, At least one transistor connected at one end to the branch point; and comprising an impedance element connected between at least one transistor and ground, A semiconductor device having a protection circuit, wherein at least one of the transistors has an impedance value that changes depending on the corresponding voltage.

7. In paragraph 6, The above impedance fluctuation part is, A semiconductor device having a protection circuit, characterized in that it further comprises a voltage limiter connected between the branch point and the at least one transistor.

Images