Serial port module with delayed power-on and IoT test fixture
By designing a serial port module with delayed power-on, the problem of module damage caused by overvoltage and high current was solved, achieving a stable voltage and current supply and ensuring the reliability and security of serial communication.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HUIZHOU GAOSHENGDA TECH CO LTD
- Filing Date
- 2022-11-28
- Publication Date
- 2026-05-26
AI Technical Summary
Existing serial port modules are prone to damage during mass production testing due to overcharging and high current, making them unsuitable for large-volume module testing and programming.
A serial port module with delayed power-on is designed, including a main control module, a delay module, a power distribution switch module, a serial port output module, a level control module, and a power supply module that are electrically connected. The delay module provides a power-on delay for the device under test, the voltage regulator provides stable voltage and current, the level control module controls the signal on and off, and the electrostatic tube prevents reverse current.
It solves the problem of module damage caused by instantaneous voltage and overcharging current, provides stable voltage and current, reduces data transmission errors, and ensures the reliability and security of serial communication.
Smart Images
Figure CN115865071B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of serial port module technology, specifically a serial port module with delayed power-on and an IoT test fixture. Background Technology
[0002] In today's world, the concept of whole-house intelligence is widely promoted, and smart products have entered countless households. While people still primarily need products like light bulbs, refrigerators, air conditioners, washing machines, and televisions—essential items for 21st-century life—they have also spurred the ingenuity of many "lazy" individuals. Smart control of light bulbs, refrigerators, air conditioners, washing machines, and televisions—via mobile apps, cloud control, and gesture control—is becoming increasingly sophisticated, greatly facilitating modern life. Achieving this more intelligent control inevitably relies on WiFi smart control modules. The rapid growth of these modules has also led to the use of serial ports in testing tools. Various modules are now available on the market. Existing serial port modules generally meet the functions of testing and programming, but when introduced into mass production testing modules, there is a risk of overcharging and high current damaging the modules. Existing serial port output modules cannot be used for large-scale module testing and programming.
[0003] Therefore, a serial port module with delayed power-on was designed. Summary of the Invention
[0004] To address the aforementioned issues, this invention provides a serial port module with delayed power-on, which solves the problem of traditional modules causing damage to the serial port or the device under test due to instantaneous voltage and overcharge current.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A serial port module with delayed power-on includes a main control module, a delay module, a power distribution switch module, a serial port output module, a level control module, and a power supply module that are electrically connected.
[0007] The power module is connected to an external power source to provide different operating voltages and currents to other modules in the module.
[0008] The main control module is electrically connected to the power module and the device under test, respectively. It is controlled by the software, moves data from memory, packages the data, converts it from serial to serial, and outputs it to the outside of the main control module.
[0009] The delay module is electrically connected to the power distribution switch module to provide a power-on delay for the power output to the device;
[0010] The power distribution switch module is electrically connected to the device under test and controls the power supply to the device under test.
[0011] The level control module is electrically connected to the power module, the delay module, and the device under test, respectively.
[0012] The serial port output module is connected to the device under test to control the on / off state of the signal path.
[0013] Optionally, in one embodiment of the present invention, the power module includes a power connection unit, a power conversion unit, a voltage regulator unit, and a voltage switching unit. The power connection unit is electrically connected to an external power source to provide an input voltage, and the power connection unit is electrically connected to both the voltage regulator unit and the voltage switching unit. The voltage switching unit is electrically connected to the power conversion unit, and the power conversion unit is electrically connected to the delay module.
[0014] Optionally, in one embodiment of the present invention, the delay module includes a first delay unit and a second delay unit electrically connected. The input terminal of the first delay unit is electrically connected to the power conversion unit, and the output terminal is electrically connected to the second delay unit, the level control module and the serial port output module respectively. The output terminal of the second delay unit is electrically connected to the power distribution switch module.
[0015] Optionally, in one embodiment of the present invention, the serial port module further includes a connection terminal J2, which is electrically connected to the power distribution switch module, the serial port output module, the power conversion unit and the level control module respectively.
[0016] Optionally, in one embodiment of the present invention, a jumper JP1 is connected between the connection terminal J2 and the signal input terminal of the power conversion unit.
[0017] Optionally, in one embodiment of the present invention, the first delay unit and the second delay unit are respectively provided with a first power monitoring chip U5 and a second power monitoring chip U8. The voltage input terminal VDD of the first power monitoring chip U5 is electrically connected to the signal output terminal Y of the power conversion unit. The reset terminal RST of the first power monitoring chip U5 is electrically connected to the voltage input terminal VDD of the second power monitoring chip U8. The reset terminal RST of the second power monitoring chip U8 is electrically connected to the control terminals IN1 and IN2 of the serial port output module.
[0018] Optionally, in one embodiment of the present invention, the level control module includes a transistor U7 and resistors R11, R12, and R13. One end of resistor R12 is connected to the emitter of transistor U7, and the other end is grounded. Resistor R13 is connected in series with the base of transistor U7. Resistor R11 is connected in series with the collector of transistor U7. The collector of transistor U7 is electrically connected to the output terminal of the voltage regulator unit. The emitter of transistor U7 is electrically connected to pin 10 of connection terminal J2. The base of transistor U7 is electrically connected to the reset terminal RST of the first power monitoring chip U5.
[0019] Optionally, in one embodiment of the present invention, the power distribution switch module includes a power switch unit and a protection unit. The protection circuit unit is electrically connected to the power switch unit, the level control module, and the serial port output module, respectively. The protection circuit unit includes a grounded Zener diode D4 and grounded electrostatic discharge tubes D5, D6, and D7. The output terminal OUT of the power switch unit is connected to pin 3 of the connection terminal J2 and the Zener diode D4 is connected on the connection line. The normally open switch path NO1 of the serial port output module is electrically connected to pin 1 of the connection terminal J2 and the electrostatic discharge tube D5 is connected on the connection line. The normally open switch path NO2 of the serial port output module is electrically connected to pin 2 of the connection terminal J2 and the electrostatic discharge tube D6 is connected on the connection line. The electrostatic discharge tube D7 is connected to the emitter of the transistor U7.
[0020] Optionally, in one embodiment of the present invention, the voltage switching unit includes a switcher, the input terminal of which is connected to different voltage terminals respectively, and outputs different voltages by switching. A resistor is connected between the input terminal and the output terminal of the switcher respectively.
[0021] An IoT test fixture includes a serial port module, wherein the serial port module is the aforementioned serial port module with delayed power-on.
[0022] Beneficial effects of the invention
[0023] This invention provides a serial port module with delayed power-on. The module incorporates a delay circuit, solving the problems of traditional modules where instantaneous voltage and overcurrent can cause damage to the serial port or the device under test, and the need for repeated power-on. A voltage regulator provides stable operating voltage and current. An electrostatic discharge tube is included in the module circuit for reverse polarity protection and voltage stabilization. The delay function reduces data transmission errors during serial communication, making transmission more reliable. A level control module ensures the module can be powered by a larger current. Attached Figure Description
[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0025] Figure 1 A schematic diagram of the complete circuit configuration of Embodiment 1 of the present invention;
[0026] Figure 2 Schematic diagram of the main control module in Embodiment 1 of the present invention;
[0027] Figure 3 Schematic diagram of the USB interface in Embodiment 1 of the present invention;
[0028] Figure 4Schematic diagram of the voltage regulator unit in Embodiment 1 of the present invention;
[0029] Figure 5 Embodiment 1 of the present invention: power conversion unit;
[0030] Figure 6 Schematic diagram of the delay module in Embodiment 1 of the present invention
[0031] Figure 7 Schematic diagram of the level control module in Embodiment 1 of the present invention;
[0032] Figure 8 Schematic diagram of the voltage switching unit in Embodiment 1 of the present invention;
[0033] Figure 9 Schematic diagram of the serial port output module in Embodiment 1 of the present invention;
[0034] Figure 10 Schematic diagram of the power switch unit in Embodiment 1 of the present invention;
[0035] Figure 11 Schematic diagram of the protection circuit unit in Embodiment 1 of the present invention;
[0036] Figure 12 Schematic diagram of connection terminal J2 in Embodiment 1 of the present invention;
[0037] Figure 13 Schematic diagram of jumper JP1 in Embodiment 1 of the present invention. Detailed Implementation
[0038] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.
[0039] Example 1
[0040] Existing serial port modules generally meet the functions of testing and programming. However, when introducing mass production testing modules, there is a tendency for overcharging and high current to burn out the modules, making them unsuitable for large-volume module testing and programming. Therefore, to address this issue, a serial port module with delayed power-on was designed, and its specific solution is as follows:
[0041] like Figure 1-13 As shown, a serial port module with delayed power-on includes a main control module, a delay module, a power distribution switch module, a serial port output module, a level control module, and a power supply module that are electrically connected.
[0042] like Figure 12As shown, the serial port module also includes a connection terminal J2, which is electrically connected to the power distribution switch module, the serial port output module, the power conversion unit and the level control module respectively. The connection terminal J2 includes 10 pins for connecting each module.
[0043] A jumper JP1 is connected between terminal J2 and the signal input terminal of the power conversion unit. JP1 shorts DUT_ON_L to ground for debugging the power supply of the entire circuit.
[0044] The power module is connected to an external power source to provide different operating voltages and currents to other modules in the module.
[0045] like Figure 3-5 As shown in Figure 8, specifically, the power module includes a power connection unit, a power conversion unit, a voltage regulator unit, and a voltage switching unit. The power connection unit is electrically connected to an external power supply to provide input voltage, and the power connection unit is electrically connected to the voltage regulator unit and the voltage switching unit respectively. The voltage switching unit is electrically connected to the power conversion unit, and the power conversion unit is electrically connected to the delay module.
[0046] like Figure 3 As shown, in this embodiment, the power connection unit is a USB interface. The USB interface is connected to the power supply device and plugged into the computer's interface. The computer provides 5V voltage. The module inputs 5V power voltage through the USB interface. The voltage terminal VBUS and the positive and negative terminals D+ and D- of the data terminal of the USB interface are respectively connected to grounding electrostatic tubes D1, D2, and D3. The electrostatic tubes D1, D2, and D3 are mainly used for electrostatic protection to prevent the USB interface from being damaged by electrostatic discharge.
[0047] like Figure 4 As shown, in this embodiment, the voltage regulator unit includes a voltage regulator chip U1. The input terminal of the voltage regulator chip U1 is electrically connected to the voltage terminal VBUS of the USB interface. The voltage regulator chip U1 steps down the 5V voltage to a 3.3V voltage output. The voltage regulator chip U1 is mainly used to provide a stable 3.3V voltage.
[0048] like Figure 5 As shown, in this embodiment, the power conversion unit includes a logic gate chip U3. The voltage input terminal VCC and signal input terminal A of U3 are electrically connected to pin 2 of the switch J3. The signal output terminal Y of U3 is electrically connected to the voltage input terminal VDD of the first delay unit. The power conversion unit uses a rated application of loff for partial shutdown to prevent damage current backflow.
[0049] The main control module is electrically connected to the power module and the device under test, respectively. It is controlled by the software, moves data from memory, packages the data, converts it from serial to serial, and outputs it to the outside of the main control module.
[0050] like Figure 2 , 3 As shown, the main control module includes a main control chip U2, which is a USB interface chip. The voltage input terminal VCC of U2 is electrically connected to the voltage terminal of the USB interface, using a 5V operating voltage. The I / O voltage terminal VCCIO of U2 is electrically connected to pin 2 of the switch J3. The two configurable I / O terminals USB-DP and USB-DM of U2 are electrically connected to the positive and negative terminals D+ and D- of the data terminal of the USB interface, respectively. The control output terminal RTS and the control input terminal CTS of U2 are connected to the device through the connection terminal J2. The data output terminal TXD and the data receiving terminal RXD of U2 are connected to the switching terminals COM1 and COM2 of the analog switch chip U6, respectively.
[0051] The delay module is electrically connected to the power distribution switch module to provide a power-on delay for the power output to the equipment;
[0052] In this embodiment, the delay module provides a 200ms power-on delay for the power output to the device. The delay module includes a first delay unit and a second delay unit that are electrically connected. The input terminal of the first delay unit is electrically connected to the power conversion unit, and the output terminal is electrically connected to the second delay unit, the level control module, and the serial port output module, respectively. The output terminal of the second delay unit is electrically connected to the power distribution switch module.
[0053] like Figure 6 As shown, specifically, the first delay unit and the second delay unit are respectively equipped with a first power monitoring chip U5 and a second power monitoring chip U8. The voltage input terminal VDD of the first power monitoring chip U5 is electrically connected to the signal output terminal Y of the power conversion unit. The reset terminal RST of the first power monitoring chip U5 is electrically connected to the voltage input terminal VDD of the second power monitoring chip U8. The reset terminal RST of the second power monitoring chip U8 is electrically connected to the control terminals IN1 and IN2 of the analog switch chip U6. The power monitoring chips U5 and U8 are used for power monitoring to maintain power stability and delay the power output to the device by 200ms. The power monitoring chip U5 performs power monitoring and delay on DUT_ON_H and VCC_DUT_EN_1. U5 outputs VCC_DUT_EN_1, and U8 outputs VCC_DUT_EN_2, which is connected to the logic enable terminal EN of U4.
[0054] The power distribution switch module is electrically connected to the device under test and controls the power supply to the device under test.
[0055] like Figure 10 , 11As shown, the power distribution switch module includes a power switch unit and a protection unit. The protection circuit unit is electrically connected to the power switch unit, the level control module, and the serial port output module, respectively. The protection circuit unit includes a grounded Zener diode D4 and grounded electrostatic discharge tubes D5, D6, and D7. The power switch unit includes a power load switch chip U4. The output terminal OUT of U4 is connected to pin 3 of the connection terminal J2 and a Zener diode D4 is connected on the connection line. The normally open switch path NO1 of the analog switch chip U6 is electrically connected to pin 1 of the connection terminal J2 and an electrostatic discharge tube D5 is connected on the connection line. The normally open switch path NO2 of the analog switch chip U6 is electrically connected to pin 2 of the connection terminal J2 and an electrostatic discharge tube D6 is connected on the connection line. The electrostatic discharge tube D7 is connected to the emitter of the transistor U7.
[0056] like Figure 8 As shown, the voltage switching unit includes a switcher J3, which has two input terminals. The two input terminals are connected to different voltage terminals respectively. Specifically, pin 1 of the switcher J3 is electrically connected to the voltage terminal of the USB interface, pin 3 is connected to the output terminal OUT of the voltage regulator unit U1, and pin 2 is the output pin. Different voltages are output by switching. Resistors R16 and R17 are connected between the two input terminals and the output terminal of the switcher J3 respectively.
[0057] The level control module is electrically connected to the power module, the delay module, and the device under test, respectively.
[0058] like Figure 7 As shown, in this embodiment, the level control module includes a transistor U7 and resistors R11, R12, and R13. One end of resistor R12 is connected to the emitter of transistor U7, and the other end is grounded. Resistor R13 is connected in series with the base of transistor U7. Resistor R11 is connected in series with the collector of transistor U7. The collector of transistor U7 is electrically connected to the output terminal of the voltage regulator unit. The emitter of transistor U7 is electrically connected to pin 10 of the connection terminal J2. The base of transistor U7 is electrically connected to the reset terminal RST of the first power monitoring chip U5. The high and low levels of the SEL selection terminal are controlled by the NPN transistor.
[0059] The serial port output module is connected to the device under test to control the on / off state of the signal path.
[0060] like Figure 9 As shown, the serial port output module includes an analog switch chip U6 whose voltage input terminal VCC is electrically connected to pin 2 of the switcher J3. The switching terminals COM1 and COM2 of U6 are connected to normally open switch paths NO1 and NO2, respectively. The normally open switch paths NO1 and NO2 are connected to the device through the connection terminal J2. The control pins IN1 and IN2 of U6 are connected to the output of the first delay unit.
[0061] Circuit operating principle:
[0062] like Figure 1-13As shown, the design scheme connects to the host device (a computer) via USB MALE. Electrostatic discharge transistors D1, D2, and D3 are connected to VBUS, D+, and D- to provide reverse polarity protection and voltage regulation, resulting in a 5V voltage VBUS_5V. The data terminals are D+ and D-. VBUS_5V is connected to the voltage regulator chip U1, outputting a 3.3V voltage VCC_3P3V. Jumpers for VBUS_5V and VCC_3P3V are added, corresponding to resistors R16 and R17 in switch J3. Switch J3 allows for free selection of the voltage obtained from VCC_DUT, reserved for signal integrity debugging of this design. VBUS_5V is used to supply power to the main control chip U1. 2. Power supply: Connected to the I / O voltage terminal VCCIO. The positive and negative terminals D+ and D- of the data terminal are connected to the configurable I / O terminals USB-DP and USB-DM of the main control chip U2, respectively, for USB-to-UART serial port conversion, resulting in D_RXD, D_TXD, U_RTS, and U_CTS. VCC_DUT is enabled, and the SEL selection terminal is controlled by transistor U7 to achieve high and low levels. VCC_OUT follows the power supply voltage of the main control chip U2 and is connected to VCCIO. This pin is designed for USB bus power supply and can be connected to 3V3OUT at +3.3V level, or connected to VCC at +5V CMOS level. This pin can also be sequentially provided with external +1.8V to +2.8V power supply for discharge: discharge from the lower level. It should be noted that in this case, this supply should be from the same source as the VCC supply. This means that in a bus-powered design, the regulator provided by the +5V on the USB bus should be used. This PIN can control power delay and voltage regulation. This circuit converts VCC_DUT through logic gate chip U3. U3 is used for applications that partially shut down the rated Ioff. The Ioff circuit disables the -2000-V human body model output to prevent damage current backflow and obtains the voltage DUT_ON_H. DUT_ON_H passes through the first power monitoring chip U5 to obtain VCC_DUT_EN_1. VCC_DUT_EN_1 passes through the second power monitoring chip U8 to obtain VCC_DUT_EN_2. VCC_DUT_EN_1 controls the analog switch chip U6. The analog switch chip U6 is a dual-channel single-pole single-throw analog switch. U6 provides low on-state resistance and excellent inter-channel on-state resistance matching, and has excellent total harmonic distortion performance with extremely low power consumption.This line tunes D_TXD and D_RXD to DUT_TXD and DUT_RXD via a switch, using them as a serial port for terminal use. VCC_DUT_EN_2 controls the shutdown of VCC_DUT and the setting of the power distribution switch. This can handle applications with large capacitors that may encounter load and short circuits. When the output load exceeds the current limit and a short circuit occurs, the device limits the output by switching to constant current mode, pulling the overcurrent logic unit to output a low level, thereby protecting the circuit. After internal conversion, this line produces VCC_DUT_OUT output. When using V... When VCC_DUT_OUT is applied, this voltage will be delayed by 200ms compared to the normal power-on voltage. An electrostatic discharge (ESD) protection diode is added to the VCC_DUT_OUT power supply for reverse polarity protection. Bidirectional transient suppression diodes (D5, D6, and D7) are added to DUT_TXD, DUT_RXD, and SEL1_H for voltage regulation. These are used through the main interface signal output, defined as DUT_TXD, DUT_RXD, DUT_VCC, U_RTS, U_CTS, and SEL1_H. This solution is compatible with the debugging of most IoT solution modules.
[0063] One embodiment discloses an IoT test fixture, including a serial port module, which is the aforementioned serial port module with delayed power-on.
[0064] The serial port module of this invention features a delay circuit, which solves the problems of traditional modules being damaged by instantaneous voltage and overcharge current, leading to breakdown of the serial port or the device under test, and the need for repeated power-on of the module. A voltage regulator provides stable operating voltage and current. An electrostatic discharge tube is added to the module circuit for reverse polarity protection and voltage regulation. The delay function reduces data transmission errors during serial communication, making transmission more reliable. A level control module ensures that the module can be powered by a larger current.
[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A serial port circuit with delayed power-on, characterized in that, It includes a main control module, a delay module, a power distribution switch module, a serial port output module, a level control module, and a power supply module with electrical connections; The power module is connected to an external power source to provide different operating voltages and currents to other modules in the module. The main control module is electrically connected to the power module and the device under test, respectively. It is controlled by the software, moves data from memory, packages the data, converts it from serial to serial, and outputs it to the outside of the main control module. The delay module is electrically connected to the power distribution switch module to provide a power-on delay for the power output to the device; The power distribution switch module is electrically connected to the device under test and controls the power supply to the device under test. The level control module is electrically connected to the power module, the delay module, and the device under test, respectively. The serial port output module is connected to the device under test to control the on / off state of the signal path. The power supply module includes a power connection unit, a power conversion unit, a voltage regulator unit, and a voltage switching unit. The power connection unit is electrically connected to an external power supply to provide input voltage, and is also electrically connected to the voltage regulator unit and the voltage switching unit. The voltage switching unit is electrically connected to the power conversion unit, and the power conversion unit is electrically connected to a delay module. The delay module includes a first delay unit and a second delay unit that are electrically connected. The input terminal of the first delay unit is electrically connected to the power conversion unit, and its output terminal is electrically connected to the second delay unit, the level control module, and the serial port output module. The output terminal of the second delay unit is electrically connected to a power distribution switch module. The level control module includes a transistor U7 and resistors R11, R12, and R13. One end of resistor R12 is connected to the emitter of transistor U7, and the other end is grounded. Resistor R13 is connected in series with the base of transistor U7. Resistor R11... The collector of transistor U7 is connected in series, and the collector of transistor U7 is electrically connected to the output terminal of the voltage regulator unit. The emitter of transistor U7 is electrically connected to pin 10 of connection terminal J2, and the base of transistor U7 is electrically connected to the reset terminal RST of the first power monitoring chip U5. The power distribution switch module includes a power switch unit and a protection unit. The protection unit is electrically connected to the power switch unit, the level control module, and the serial port output module, respectively. The protection unit includes a grounded Zener diode D4 and a grounded static diode D5. The power switch unit's output terminal OUT is connected to pin 3 of terminal J2, and a Zener diode D4 is connected to the connection line. The normally open switch path NO1 of the serial port output module is electrically connected to pin 1 of terminal J2, and an electrostatic discharge tube D5 is connected to the connection line. The normally open switch path NO2 of the serial port output module is electrically connected to pin 2 of terminal J2, and an electrostatic discharge tube D6 is connected to the connection line. The electrostatic discharge tube D7 is connected to the emitter of transistor U7.
2. The serial port circuit with delayed power-on according to claim 1, characterized in that: The serial port circuit also includes a connection terminal J2, which is electrically connected to the power distribution switch module, the serial port output module, the power conversion unit, and the level control module.
3. The serial port circuit with delayed power-on according to claim 2, characterized in that: A jumper JP1 is connected between the connection terminal J2 and the signal input terminal of the power conversion unit.
4. The serial port circuit with delayed power-on according to claim 1, characterized in that: The first delay unit and the second delay unit are respectively equipped with a first power monitoring chip U5 and a second power monitoring chip U8. The voltage input terminal VDD of the first power monitoring chip U5 is electrically connected to the signal output terminal Y of the power conversion unit. The reset terminal RST of the first power monitoring chip U5 is electrically connected to the voltage input terminal VDD of the second power monitoring chip U8. The reset terminal RST of the second power monitoring chip U8 is electrically connected to the control terminals IN1 and IN2 of the serial port output module.
5. The serial port circuit with delayed power-on according to claim 1, characterized in that: The voltage switching unit includes a switcher, the input terminal of which is connected to different voltage terminals respectively, and outputs different voltages by switching. A resistor is connected between the input terminal and the output terminal of the switcher respectively.
6. An IoT test fixture, comprising a serial port circuit, characterized in that, The serial port circuit is the serial port circuit with delayed power-on as described in any one of claims 1-5.