CN-122026891-A - Pin multiplexing circuit of data conversion chip

CN122026891ACN 122026891 ACN122026891 ACN 122026891ACN-122026891-A

Abstract

The invention provides a data conversion chip pin multiplexing circuit which comprises a voltage division module, a mode adjusting module and a pin multiplexing control module, wherein the voltage division module is used for dividing a power supply voltage of a data conversion chip into intervals and generating at least two reference voltage signals based on interval division results, the mode adjusting module is used for comparing the reference voltage signals with external input voltage signals and generating a mode adjusting signal according to comparison results, and the pin multiplexing control module is used for starting or closing pin multiplexing according to the first mode adjusting signal. The invention can be compatible with various serial communication protocols without adding additional pins, and can realize the minimized multiplexing of the pins.

Inventors

LIU SHUKAI
CHEN YANG
TANG SHULIN
CHEN ZHIMING

Assignees

长沙泰科阳微电子有限公司

Dates

Publication Date: 20260512
Application Date: 20260408

Claims (10)

1. The data conversion chip pin multiplexing circuit is characterized by comprising a voltage division module, a mode adjusting module and a pin multiplexing control module; The data conversion device comprises a voltage dividing module, a mode adjusting module, a voltage dividing module and a power supply voltage control module, wherein the voltage dividing module is used for dividing a power supply voltage of a data conversion chip in intervals and generating at least two reference voltage signals based on an interval dividing result; the mode adjusting module is used for comparing the reference voltage signal with an external input voltage signal and generating a mode adjusting signal according to a comparison result; the system comprises a data conversion chip, a pin multiplexing control module, a mode regulation signal, a first output end of the mode regulation module, a second output end of the mode regulation module, a pin multiplexing control module and a power supply, wherein the mode regulation signal is used for regulating the working state of the data conversion chip, the mode regulation signal comprises a first mode regulation signal and a second mode regulation signal, the first mode regulation signal is used for controlling the pin multiplexing control module to start pin multiplexing or close pin multiplexing, the second mode regulation signal is used for controlling the data conversion chip to be turned on and off, the second input end of the mode regulation module is connected to a functional pin of the data conversion chip and is used for receiving the external input voltage signal, the first output end of the mode regulation module is connected to an internal power supply starting and stopping circuit of the data conversion chip, and the second output end of the mode regulation module is connected to the input end of the pin multiplexing control module; The pin multiplexing control module is used for starting or closing pin multiplexing according to the first mode adjusting signal, and the output end of the pin multiplexing control module is connected to a target pin.
2. The data conversion chip pin multiplexing circuit according to claim 1, wherein the voltage dividing module is formed by connecting a first resistor, a second resistor and a third resistor in series, one end of the first resistor is connected to a power pin of the data conversion chip, the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the third resistor, and the other end of the third resistor is connected to a ground pin of the data conversion chip; an output port is led out from the middle of the first resistor and the second resistor and used for transmitting a first reference voltage signal, another output port is led out from the middle of the second resistor and the third resistor and used for transmitting a second reference voltage signal, and the first reference voltage signal is larger than the second reference voltage signal.
3. The data conversion chip pin multiplexing circuit of claim 2, wherein the first resistor, the second resistor, and the third resistor are equal in resistance.
4. The data conversion chip pin multiplexing circuit of claim 3, wherein the mode adjustment module comprises a first comparator, a second comparator, a first inverter, a second inverter, a nand gate, a third inverter, a fourth inverter, a nor gate; The positive input end of the first comparator, the negative input end of the second comparator and the input end of the fourth inverter are connected in parallel and then connected to the functional pin; the negative input end of the first comparator is connected between the first resistor and the second resistor, and the positive input end of the second comparator is connected between the second resistor and the third resistor; the output end of the first comparator is connected to the input end of the first inverter, and the output end of the first inverter is connected to the first input end of the NAND gate; the output end of the second comparator is connected to the input end of the second inverter, and the output end of the second inverter is connected to the second input end of the NAND gate; The output end of the NAND gate is connected to the input end of the third inverter, and the output end of the third inverter is respectively connected to the input end of the pin multiplexing control module and the first input end of the NOR gate; the output end of the fourth inverter is connected to the second input end of the NOR gate, and the output end of the NOR gate is connected with the internal start-up circuit; and the output end of the NOR gate outputs the second mode adjusting signal.
5. The pin multiplexing circuit of the data conversion chip according to claim 4, wherein the pin multiplexing control module comprises a plurality of one-out-of-two multiplexers; The control end of each of the two-way multiplexers is connected to the output end of the third inverter and is used for receiving the first mode adjusting signal, the first input end of the two-way multiplexer is connected to the data input end inside the chip, the second input end of the two-way multiplexer is connected to the serial protocol interface signal end, and the output end of the two-way multiplexer is connected to the target pin.
6. The data conversion chip pin multiplexing circuit of claim 5, wherein the one-out-of-two multiplexer is implemented using a transmission gate structure.
7. The data conversion chip pin multiplexing circuit of claim 5, wherein the serial protocol interface signal terminal is an SPI protocol interface signal terminal, comprising SCK, MOSI, MISO, CS.
8. The data conversion chip pin multiplexing circuit of claim 5, wherein the serial protocol interface signal terminal is an I2C protocol interface signal terminal comprising SDA and SCL.
9. The data conversion chip pin multiplexing circuit of claim 4, wherein the mode adjustment module is configured to: When the external input voltage signal is smaller than the second reference voltage signal, the first mode adjusting signal controls the multiplexing of the closed pins, and the second mode adjusting signal controls the data conversion chip to be opened; When the external input voltage signal is between the second reference voltage signal and the first reference voltage signal, the first mode adjusting signal controls the starting pin multiplexing, and the second mode adjusting signal controls the starting of the data conversion chip; when the external input voltage signal is larger than the first reference voltage signal, the first mode adjusting signal controls the shutdown pin multiplexing, and the second mode adjusting signal controls the shutdown of the data conversion chip.
10. The data conversion chip pin multiplexing circuit of claim 4, wherein the first comparator and/or the second comparator is a comparator with hysteresis function for suppressing a mode error switching when the external input voltage signal is at a threshold critical point.

Description

Pin multiplexing circuit of data conversion chip Technical Field The invention belongs to the technical field of integrated circuits, and particularly relates to a pin multiplexing circuit of a data conversion chip, which is particularly suitable for realizing pin multiplexing control of various serial communication protocols in miniaturized packaging of a high-precision data conversion chip. Background Along with the increasing demands of the fields of the internet of things, wearable equipment, industrial control and the like for chip miniaturization and high integration, the chip packaging size becomes one of key factors restricting product design. The package size is mainly limited by the number of chip pins, the fewer pins, the smaller the package can be, the lower the cost, and the better the signal integrity. However, high precision data conversion chips (ADC/DAC chips, e.g., 14 bits/16 bits) typically require calibration prior to shipment to correct for capacitance/resistance mismatch problems due to process variations, ensuring conversion accuracy. The calibration process typically requires configuration of on-chip registers via a serial communication protocol, such as I2C, SPI. In the conventional scheme, the I2C protocol requires two pins of SDA and SCL, while the SPI protocol requires SCK, MOSI, MISO, CS four pins, which directly conflict with the "few pins" design goal. In the prior art, some pin multiplexing schemes exist, such as protocol switching through a switching module and interface multiplexing through configuration of a main device, but these schemes still need at least two pins, and the requirement of 'zero-additional pins' cannot be fundamentally solved. Disclosure of Invention The invention aims to solve the technical problem of providing a data conversion chip pin multiplexing circuit which is compatible with various serial communication protocols without adding additional pins and realizes the minimum multiplexing of pins. The invention provides a data conversion chip pin multiplexing circuit, which comprises a voltage division module, a mode adjusting module and a pin multiplexing control module, wherein the voltage division module is connected with the mode adjusting module; The data conversion device comprises a data conversion chip, a voltage division module, a mode adjustment module, a voltage division module, a voltage control module and a control module, wherein the data conversion chip is used for converting a power voltage of the data conversion chip into a power voltage; The mode adjusting module is used for comparing the reference voltage signal with an external input voltage signal and generating a mode adjusting signal according to a comparison result; the system comprises a data conversion chip, a pin multiplexing control module, a mode regulation signal, a second mode regulation signal, a first output end of the mode regulation module, a second output end of the mode regulation module, a first control module and a second control module, wherein the mode regulation signal is used for regulating the working state of the data conversion chip; The pin multiplexing control module is used for starting or closing the pin multiplexing according to the first mode adjusting signal, and the output end of the pin multiplexing control module is connected to the target pin. Optionally, the voltage dividing module is formed by connecting a first resistor, a second resistor and a third resistor in series, wherein one end of the first resistor is connected to a power pin of the data conversion chip, the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the third resistor, and the other end of the third resistor is connected to a grounding pin of the data conversion chip; an output port is led out from the middle of the first resistor and the second resistor and used for transmitting a first reference voltage signal, another output port is led out from the middle of the second resistor and the third resistor and used for transmitting a second reference voltage signal, and the first reference voltage signal is larger than the second reference voltage signal. Optionally, the resistances of the first resistor, the second resistor and the third resistor are equal in size. Optionally, the mode adjustment module includes a first comparator, a second comparator, a first inverter, a second inverter, a nand gate, a third inverter, a fourth inverter, and a nor gate; The positive input end of the first comparator, the negative input end of the second comparator and the input end of the fourth inverter are connected in parallel and then connected to the functional pin; the negative input end of the first comparator is connected between the first resistor and the second resistor, and the positive input end of the second comparator is connected between the second resistor and the third resistor; the outp