Low-voltage key charging multi-mode LED driving chip and charging circuit

Abstract

The utility model relates to the field of charging chips, and provides a low-voltage button charging multi-mode LED driving chip, which comprises a logic circuit, a function setting circuit, an oscillator circuit, a biasing circuit, a charging circuit, a first transistor and a detection module, the output end of the logic circuit is connected with the controlled end of the oscillator circuit, the output end of the oscillator circuit is connected with the input end of the bias circuit, the output end of the bias circuit is connected with the grid electrode of the first transistor through the charging circuit, the source electrode of the first transistor is connected with a VDD port, and the drain electrode of the first transistor is connected with a BAT port. The VDD port is used for being connected with a charging power supply, the BAT port is used for being connected with the positive electrode of a battery, the input end of the detection module is connected with the VDD port and the BAT port, and the output end of the detection module is connected with the input end of the logic circuit; the utility model has different output modes and protection functions.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of charging chip, specifically, relate to a low voltage key charging multi -mode LED drive chip. BACKGROUND

[0002] With the wide application of lithium battery, the use of lithium battery charging chip is also more and more widely, and the existing charging chip is mostly single mode, and the battery protection function is insufficient, which cannot meet the user's use demand. INVENTION CONTENTS

[0003] The utility model solves the problem of how to provide a low voltage key charging LED drive chip with different output modes and protection functions.

[0004] In order to solve the above problem, the utility model provides a low voltage key charging multi -mode LED drive chip, including: logic circuit, function setting circuit, oscillator circuit, bias circuit, charging circuit, first transistor and detection module, the input end of function setting circuit is connected with the logic circuit, the output end of logic circuit is connected with the controlled end of oscillator circuit, the output end of oscillator circuit is connected with the input end of bias circuit, the output end of bias circuit is connected with the gate of first transistor through charging circuit, the source of first transistor is connected with VDD port, and the drain is connected with BAT port, VDD port is used for connecting charging power supply, BAT port is used for connecting the positive pole of battery, the input end of detection module is connected with VDD port and BAT port respectively, and the output end is connected with the input end of logic circuit.

[0005] Further, the function setting circuit includes a key function circuit and a setting port circuit.

[0006] Further, one end of the key function circuit is connected with port K1, and the other end is connected with the input end of the logic circuit, and the port K1 is used for connecting the external setting key.

[0007] Further, the setting port circuit includes a port SEL1, a port SEL2 and a port LSET connected with the input end of the logic circuit.

[0008] Further, the detection module includes a first detection circuit and a second detection circuit, the input end of the first detection circuit is connected with the VDD port, and the output end is connected with the logic circuit, the input end of the second detection circuit is connected with the BAT port, and the output end is connected with the logic circuit.

[0009] Further, the detection module further includes a third detection circuit, the input end of the third detection circuit is connected with a thermistor arranged on the chip, and the output end is connected with the logic circuit.

[0010] Further, the forward LED driving circuit and the reverse LED driving circuit are further included, the input end of the forward LED driving circuit is connected with the logic circuit, the output end is connected with an LED port, the LED port is used for connecting the positive pole of an external LED lamp, the input end of the reverse LED driving circuit is connected with the logic circuit, the output end is connected with a VOUT port, and the VOUT port is used for connecting the negative pole of the external LED lamp.

[0011] The utility model further provides a charging circuit, including first chip that adopts above low voltage button charges multi -mode LED drive chip, the built -in pull up of LSET port of first chip, the BAT port of first chip connects first battery positive pole, first battery negative pole ground, VDD port connects the power supply port of USB interface, K1 port is grounded through first button, LED port is grounded through first LED lamp, VOUT port connects first battery positive pole through second LED lamp.

[0012] Compared with the prior art, the utility model has the advantages that:

[0013] The function setting circuit of the chip is connected with the logic circuit, the logic circuit receives corresponding signals by different connection states of the three setting ports in the function setting circuit, the control mode of the bias signal to the charging transistor is changed, the chip has corresponding output modes when charging, in the detection module, the control of each mode is ensured by detecting the power supply and the battery voltage, the charging voltage protection is also realized, the chip temperature is collected when charging by the thermal element arranged in the detection module on the chip, the charging temperature protection is realized, the chip has multiple modes and protection functions, and the use demand of users is met. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the whole structure schematic drawing of low voltage button charges multi -mode LED drive chip of the utility model embodiment;

[0015] Figure 2 It is the packaging mode schematic drawing of low voltage button charges multi -mode LED drive chip of the utility model embodiment;

[0016] Figure 3 It is the principle structure schematic drawing of charging circuit of the utility model embodiment using ESOP8 package;

[0017] Figure 4 It is the principle structure schematic drawing of charging circuit of the utility model embodiment using SOT23-6 package. DETAILED DESCRIPTION

[0018] In order to make the above purpose, features and advantages of the utility model more obvious and easy to understand, the specific embodiments of the utility model are explained in detail below with reference to the drawings.

[0019] In the description of the utility model, it needs to explain, unless another explicit stipulation and limit, term '' set '', '' install '', '' link '', '' connect '' should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected, can be mechanical connection, can be direct connection, also can be indirectly connected through intermediate medium, can be two element internal communication, for ordinary skilled person in the art, can understand the concrete meaning of above-mentioned term in the utility model with specific circumstances.

[0020] In the description of the specification, the description of the terms "embodiment", "one embodiment", and "one implementation" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or implementation are included in at least one embodiment or implementation of the utility model. In this specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or implementation. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or implementations in a suitable manner.

[0021] As shown in Figure 1 The utility model provides a low pressure key charging multi -mode LED drive chip, include: logic circuit, function setting circuit, oscillator circuit, bias circuit, charging circuit, first transistor and detection module, function setting circuit links the input of logic circuit, the output of logic circuit links the controlled end of oscillator circuit, the output of oscillator circuit links the input of bias circuit, the output of bias circuit links the grid of first transistor through charging circuit, the source of first transistor links VDD port, drain connects BAT port, VDD port is used for connecting charging power supply, BAT port is used for connecting the positive pole of battery, the input of detection module links VDD port and BAT port respectively, and the output links the input of logic circuit.

[0022] The function setting circuit includes a key function circuit and a setting port circuit.

[0023] One end of the key function circuit is connected to port K1, and the other end is connected to the input of the logic circuit. Port K1 is used to connect an external setting key.

[0024] The setting port circuit includes port SEL1, port SEL2 and port LSET connected to the input of the logic circuit.

[0025] The detection module includes a first detection circuit and a second detection circuit. The input of the first detection circuit is connected to the VDD port, and the output is connected to the logic circuit. The input of the second detection circuit is connected to the BAT port, and the output is connected to the logic circuit.

[0026] The detection module further comprises a third detection circuit, an input end of the third detection circuit is connected with a thermistor arranged on the chip, and an output end is connected with the logic circuit.

[0027] The forward LED driving circuit has an input end connected with the logic circuit and an output end connected with an LED port for connecting the positive pole of an external LED lamp, and the reverse LED driving circuit has an input end connected with the logic circuit and an output end connected with a VOUT port for connecting the negative pole of the external LED lamp, and the two LED lamps are used for indication during charging.

[0028] Specifically, the utility model discloses a lithium battery charge and discharge management special chip, can charge for 3.7V lithium battery when charging, and the highest current can configure 1A. Through input signal and voltage acquisition, the logic circuit passes through the corresponding duty cycle signal control bias circuit of oscillator output, and the bias signal controls the charging transistor, and makes the transistor work in different states, when VDD pin voltage rises above the threshold level or when a battery is connected with the output end of charger, a charging cycle starts. If BAT pin level is below 2.7V, then the charger enters trickle charging mode. In this mode, the chip provides 1 / 10 of the set charging current to raise the battery voltage to a safe level, so as to realize full current charging. When the voltage of BAT pin rises above 2.7V, the charger enters constant current mode, and the constant charging current is provided to the battery. When the voltage of BAT pin reaches the final floating voltage 4.2V, the chip enters constant voltage charging mode, and the charging current starts to decrease. When the charging current decreases to 1 / 10 of the set value, the charging cycle ends. Once the charging cycle is terminated, the chip immediately uses a comparator with a 3ms filter time to continuously monitor the voltage on the BAT pin. When the battery voltage drops to 4.05V, which corresponds to 80% to 90% or less of the battery capacity, the charging cycle restarts. This ensures that the battery is maintained in a fully charged state and eliminates the need for periodic charging cycle initiation.

[0029] Different charging modes can be selected according to the connection mode of port SEL1, port SEL2 and port LSET.

[0030] Port SEL1 and SEL2 can select different 4 preset duty cycle output modes according to the pull-up and pull-down connection method thereof.

[0031] The LSET pin of the port is connected to GND and features an automatic current reduction function. At 100% duty cycle output, it outputs 100% current for 0 to 3 minutes, then linearly decreases by 10% every 3 minutes. It drops to a minimum of 45% output current and maintains 45% current until the current reduction restarts the timing.

[0032] Therefore, based on the built-in pin states, the chip has two packages, such as... Figure 2 As shown: ESOP8 and SOT23-6. The ESOP8 package has an internal pull-up on the LSET pin, which is high (1) when floating and has no current reduction function when floating; the SOT23-6 package has an internal pull-down on the ISET pin, which has automatic current reduction function by default.

[0033] When using an ESOP8 package, the charging circuit of the chip in this embodiment is as follows: Figure 3 As shown, when using an SOT23-6 package, the charging circuit of the chip in this embodiment is as follows: Figure 4 As shown.

[0034] by Figure 3 For example, the LSET port of the first chip has a built-in pull-up switch, the BAT port of the first chip is connected to the positive terminal BAT+ of the first battery, the negative terminal BAT- of the first battery is grounded, the VDD port is connected to the power supply port of the USB interface USB1`, the K1 port is grounded through the first button SW1, the LED port is grounded through the first LED LED-R, and the VOUT port is connected to the positive terminal BAT+ of the first battery through the second LED LED-W.

[0035] Although the disclosure is as stated above, the scope of protection of this disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this utility model.

Claims

1. A low voltage key-charging multi-mode LED driver chip, characterized in that, It comprises: logic circuit, function setting circuit, oscillator circuit, bias circuit, charging circuit, first transistor and detection module, the input end of the function setting circuit is connected with the input end of the logic circuit, the output end of the logic circuit is connected with the controlled end of the oscillator circuit, the output end of the oscillator circuit is connected with the input end of the bias circuit, the output end of the bias circuit is connected with the gate of the first transistor through the charging circuit, the source of the first transistor is connected with the VDD port, and the drain is connected with the BAT port, the VDD port is used for connecting the charging power supply, the BAT port is used for connecting the positive electrode of the battery, the input end of the detection module is connected with the VDD port and the BAT port respectively, and the output end is connected with the input end of the logic circuit.

2. The low voltage key charge multi-mode LED driver chip according to claim 1, wherein, The function setting circuit comprises a key function circuit and a setting port circuit.

3. The low voltage key charge multi-mode LED driver chip according to claim 2, wherein, One end of the key function circuit is connected with the port K1, and the other end is connected with the input end of the logic circuit, and the port K1 is used for connecting the external setting key.

4. The low voltage key charge multi-mode LED driver chip according to claim 3, wherein, The setting port circuit comprises the port SEL1, the port SEL2 and the port LSET connected with the input end of the logic circuit.

5. The low voltage key charge multi-mode LED driver chip according to claim 4, wherein, The detection module comprises a first detection circuit and a second detection circuit, the input end of the first detection circuit is connected with the VDD port, and the output end is connected with the logic circuit, and the input end of the second detection circuit is connected with the BAT port, and the output end is connected with the logic circuit.

6. The low voltage key charge multi-mode LED driver chip of claim 5, wherein, The detection module further comprises a third detection circuit, the input end of the third detection circuit is connected with the thermistor arranged on the chip, and the output end is connected with the logic circuit.

7. The low voltage key charge multi-mode LED driver chip according to claim 6, wherein, It further comprises a forward LED drive circuit and a reverse LED drive circuit, the input end of the forward LED drive circuit is connected with the logic circuit, and the output end is connected with the LED port, and the LED port is used for connecting the positive electrode of the external LED lamp, the input end of the reverse LED drive circuit is connected with the logic circuit, and the output end is connected with the VOUT port, and the VOUT port is used for connecting the negative electrode of the external LED lamp.

8. A charging circuit comprising: The first chip and the first battery, characterized in that the first chip adopts the low-voltage key charging multi-mode LED drive chip according to any one of claims 1-7, the LSET port of the first chip is internally pulled up, the BAT port of the first chip is connected with the positive electrode of the first battery, the negative electrode of the first battery is connected with the ground, the VDD port is connected with the power supply port of the USB interface, the K1 port is connected with the ground through the first key, the LED port is connected with the ground through the first LED lamp, and the VOUT port is connected with the positive electrode of the first battery through the second LED lamp.

Images