CN215986233U

CN215986233U - 12V power supply current monitoring circuit

Info

Publication number: CN215986233U
Application number: CN202121127649.1U
Authority: CN
Inventors: 刘继伟
Original assignee: CIG Shanghai Co Ltd
Current assignee: CIG Shanghai Co Ltd
Priority date: 2021-05-24
Filing date: 2021-05-24
Publication date: 2022-03-08
Anticipated expiration: 2031-05-24

Abstract

The utility model solves the problem of realizing the current monitoring circuit design with high precision and high temperature characteristic on the common 12V system power supply of communication equipment. According to the 12V power supply current monitoring circuit provided by the utility model, the 12V power supply current monitoring circuit comprises a monitoring chip, a shunt resistor and a main control chip, wherein the monitoring chip is TPA626, and the power supply voltage of the TPA626 adopts the common voltage of 3.3V on communication equipment; the shunt resistor is a high-precision 0.01ohm resistor with 1% packaged by a patch 2512 with rated power of 1W; the TPA626 is connected with a communication interface of the main control chip by adopting IIC.

Description

12V power supply current monitoring circuit

Technical Field

The utility model belongs to the field of circuit application, and particularly relates to a 12V power supply current monitoring circuit.

Background

With the continuous development of information technology, communication equipment has more and more functions, is oriented to be wider and wider (industrial grade), has higher and higher integration level and larger energy consumption. For example, in the application of a 5G module to a communication device, since the power consumption of the 5G module is larger than that of the 4G module, if the 5G module is applied to an industrial-grade device, the environment has a higher requirement for controlling the energy consumption of the device, and the heat dissipation and comprehensive heat dissipation means thereof become a problem. In the conventional methods of adding heat radiating fins, radiating by attaching a shell and the like, comprehensive heat radiating means are more required to be considered: and the energy consumption of the module is dynamically known in real time by monitoring the current of the module, and then the power consumption is controlled by matching with the optimization of software on the service. To make such a comprehensive heat dissipation method possible, a real-time power consumption monitoring circuit with high precision and high temperature characteristics is required. Similar cases are common in communication product design, so that the design of a real-time energy consumption monitoring circuit with high precision and high temperature characteristics is an urgent requirement.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects in the prior art, the utility model provides a 12V power supply current monitoring circuit, which solves the problem of realizing the current monitoring circuit design with high precision and high temperature characteristics on a 12V system power supply commonly used by communication equipment.

According to the 12V power supply current monitoring circuit provided by the utility model, the 12V power supply current monitoring circuit comprises a monitoring chip, a shunt resistor and a main control chip, wherein the monitoring chip is TPA626, and the power supply voltage of the TPA626 adopts the common voltage of 3.3V on communication equipment; the shunt resistor is a high-precision 0.01ohm resistor with 1% packaged by a patch 2512 with rated power of 1W; the TPA626 is connected with a communication interface of the main control chip by adopting IIC.

According to the technical scheme, the TPA626 comprises one to ten pins, wherein the first pin of the TPA626 is connected with the last two high bits of the IIC address, the second pin of the TPA626 is connected with the last two low bits of the IIC address, the third pin of the TPA626 is connected with the Alert, the fourth pin of the TPA626 is connected with the IIC data signal line, the fifth pin of the TPA626 is connected with the IIC data address line, the sixth pin of the TPA626 is connected with the supply voltage of the chip, the seventh pin of the TPA is grounded, the eighth pin of the TPA is connected with the Vbus, namely the power supply to be monitored (the voltage range is 0V-30V), and the ninth pin and the tenth pin are respectively connected with two ends of the shunt resistor.

In one embodiment of the present invention, the first pin of the TPA626 is grounded via a 1K resistor.

In one embodiment of the present invention, the second pin of the TPA626 is grounded via a 1K resistor.

In one embodiment of the present invention, the pin four of the TPA626 is grounded through a 33K resistor and a 0.1 microfarad capacitor.

In one embodiment of the present invention, the pin five of the TPA626 is grounded via a 0.1 microfarad capacitor.

According to one technical scheme of the utility model, pins ten of the TPA626 are connected with a 12V power supply through a 33K resistor, pins nine of the TPA626 are connected with the 12V power supply through the 33K resistor and a 0.01ohm resistor in sequence, and a 0.01 microfarad capacitor is connected between the pins nine and ten.

According to one technical scheme, the eight-branch-line-end-to-end connection structure is further provided that the eight-branch-end-to-end connection structure comprises two branches, wherein one branch is connected with an output end of a 12V power supply through a 1K resistor, and the other branch is grounded through a 0.1 microfarad capacitor.

According to the technical scheme, six pins of the TPA626 are connected with three branches, one pin is connected with a 600 ohm resistor and then connected with a power supply, and the other two pins are connected with capacitors of 100 microfarads and 0.1 microfarads respectively and then grounded.

The utility model has the beneficial effects that:

(1) the TPA626 is adopted as an integrated monitoring chip, and a non-discrete device has better temperature characteristic and precision and can be used under industrial-grade conditions.

(2) The utility model uses a paster 2512 with rated power of 1W to package a 0.01ohm resistor with 1% high precision as a shunt resistor, and uses the characteristics of smaller current monitoring resolution and high monitoring upper limit.

(3) The main control chip of the utility model adopts IIC interface for communication with the TPA 626. And the expansibility of different main chip platforms is good.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Detailed Description

In order to facilitate an understanding of the utility model, the utility model will now be described more fully hereinafter with reference to the accompanying drawings, in which several embodiments of the utility model are shown, but which may be embodied in many different forms and are not limited to the embodiments described herein, but rather are provided for the purpose of providing a more thorough disclosure of the utility model.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present; when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present; the terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs; the terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model; as used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

As shown in fig. 1, the 12V power supply current monitoring circuit provided by the present invention adopts a digital current and power monitoring chip, TPA626, developed by 3PEAK and specially oriented to current sensing and power consumption monitoring applications to perform circuit design, the TPA626 can directly monitor the differential voltage drop at both ends of the shunt resistor, and convert it into digital output, and at the same time, can monitor the single-ended bus voltage, and calculate the power consumption information in the background, and report it to the main control chip through I2C and SMBUS.

According to the 12V power supply current monitoring circuit provided by the utility model, the 12V power supply current monitoring circuit comprises a monitoring chip, a shunt resistor and a main control chip, wherein the monitoring chip is TPA626, and the power supply voltage of the TPA626 adopts the common voltage 3.3V on communication equipment; the shunt resistor is a 1% high-precision 0.01ohm resistor packaged by a patch 2512 with rated power of 1W; the TPA626 is connected with a communication interface of the main control chip by adopting an IIC.

According to the technical scheme, the TPA626 comprises one to ten pins, wherein the first pin of the TPA626 is connected with the last two high bits of the IIC address, the second pin of the TPA626 is connected with the last two low bits of the IIC address, the third pin of the TPA626 is connected with the Alert, the fourth pin of the TPA626 is connected with the IIC data signal line, the fifth pin of the TPA is connected with the IIC data address line, the sixth pin of the TPA626 is connected with the supply voltage of the chip, the seventh pin of the TPA is grounded, the eighth pin of the TPA is connected with the Vbus, namely the power supply to be monitored (the voltage range is 0-30V), and the ninth pin and the tenth pin of the TPA are respectively connected with two ends of the shunt resistor.

In one embodiment of the present invention, pin two of the TPA626 is further configured to be grounded via a 1K resistor.

In one embodiment of the present invention, pin five of TPA626 is grounded via a 0.1 microfarad capacitor.

According to one technical scheme of the utility model, pins ten of the TPA626 are connected with a 12V power supply through a 33K resistor, pins nine of the TPA626 are connected with the 12V power supply through a 33K resistor and a 0.01ohm resistor in sequence, and a 0.01 microfarad capacitor is connected between the pins nine and ten.

According to the technical scheme, the eight-branch-line-lead-out pin comprises two branch lines, wherein one branch line is connected with the output end of a 12V power supply through a 1K resistor, and the other branch line is grounded through a 0.1 microfarad capacitor.

The current monitoring principle is as follows: TPA626 directly monitors the differential voltage drop at two ends of the shunt resistor and converts the differential voltage drop into a 16-bit ADC (analog to digital converter) with a built-in digital output TPA626, the noise is low, and the minimum level detection value is 2.5 uV. The integration precision VREF has good initial precision and temperature drift as low as about 10 ppm. The IIC used by the TPA626 and the main chip interface can directly transmit the detection result to the main chip, and the compatibility is good. The monitor current is stored in the register with the IIC address of 04 h. The current monitoring resolution of the circuit is as small as 0.25 mA.

The circuit relationship is as follows, and the minimum stepping current is I equal to 2.5 uV/R616.

The working principle of the circuit is as follows:

the description is made in connection with the description of the relevant devices or positions on fig. 1:

1. the load corresponds to the resistor R616 in FIG. 1;

2. the low offset is a sample input at +/-81.92mV full scale. (this sampling offset is built-in to TPA 626. since the high position is used for bi-directional current monitoring, this is not relevant to this patent and is not described);

3. the measured voltage is 12V _ OUT in FIG. 1;

the ADC is a 16bit (16 bit) sampler. The lowest sample output data period is 66 us.

5. And the ADC measures the variable voltage at two ends of the load in each sampling period, compares the variable voltage with the voltage on a low-bias bit, outputs current and voltage values through the conversion in the ADC and stores the current and voltage values in a corresponding register for the main chip platform to access and call corresponding data through an IIC interface.

The above-mentioned embodiments only express a certain implementation mode of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention; it should be noted that, for those skilled in the art, without departing from the concept of the present invention, several variations and modifications can be made, which are within the protection scope of the present invention; therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A12V power supply current monitoring circuit is characterized in that the 12V power supply current monitoring circuit comprises a monitoring chip, a shunt resistor and a main control chip, wherein the monitoring chip is TPA626, and the power supply voltage of the TPA626 adopts the common voltage 3.3V on communication equipment; the shunt resistor is a high-precision 0.01ohm resistor with 1% packaged by a patch 2512 with rated power of 1W; the TPA626 is connected with a communication interface of the main control chip by adopting IIC.

2. The 12V power supply current monitoring circuit according to claim 1, wherein the TPA626 comprises pins one to ten, pin one of the TPA626 is connected with the last two high bits of the IIC address, pin two is connected with the last two low bits of the IIC address, pin three is connected with Alert, pin four is connected with the IIC data signal line, pin five is connected with the IIC data address line, pin six is connected with the supply voltage of the TPA626 chip, pin seven is connected with ground, pin eight is connected with Vbus, namely the power supply to be monitored, and the voltage range of the power supply to be monitored is as follows: and the pins nine and ten are respectively connected with two ends of the shunt resistor at 0-30V.

3. The 12V power supply current monitoring circuit according to claim 2, wherein pin one of the TPA626 is grounded via a 1K resistor.

4. The 12V power supply current monitoring circuit according to claim 3, wherein pin two of the TPA626 is connected to ground via a 1K resistor.

5. The 12V power supply current monitoring circuit according to claim 4, wherein pin four of the TPA626 is connected to ground through a 33K resistor and a 0.1 microfarad capacitor.

6. The 12V power supply current monitoring circuit according to claim 5, wherein pin five of the TPA626 is grounded via a 0.1 microfarad capacitor.

7. The 12V power supply current monitoring circuit according to claim 6, wherein pin ten of TPA626 is connected with a 12V power supply via a 33K resistor, pin nine of TPA626 is connected with a 12V power supply via a 33K resistor and a 0.01ohm resistor in sequence, and a 0.01 microfarad capacitor is connected between pin nine and pin ten.

8. The 12V power supply current monitoring circuit according to claim 7, wherein the pin eight comprises two branches, one of which is connected to the output of the 12V power supply via a 1K resistor, and the other of which is grounded via a 0.1 microfarad capacitor.

9. The 12V power supply current monitoring circuit according to claim 8, wherein pin six of the TPA626 is connected to three branches, one is connected to a 600 ohm resistor and then to a power supply, and the other two are connected to capacitors of 100 microfarads and 0.1 microfarads and then to ground.