CN205229873U - Online dynamic continuously adjustable export power supply of high accuracy - Google Patents

Abstract

The utility model relates to an online dynamic continuously adjustable export power supply of high accuracy. Include: microprocessor connects simulation pick -up chip and digital potentiometer for the receipt comes from the magnitude of voltage that simulation pick -up chip gathered, separates the current voltage of calculating the power supply chip and sets up the pin resistance value, through self SPI interface configuration digital potentiometer, digital potentiometer, operational amplifier and power supply chip are connected to the output for under microprocessor's configuration, the resistance value of the voltage regulation pin of change power supply chip, operational amplifier, output connect simulation pick -up chip for the voltage of gathering the power supply chip sets up the magnitude of voltage that the pin resistance value corresponds, realizes the real -time supervision of resistance setting, simulation pick -up chip for the magnitude of voltage that the output resistance of gathering digital potentiometer was in real time changed out, and through magnitude of voltage transfer in time to the microprocessor chip that the SPI interface will be gathered, realize full closed -loop control, the power supply chip sets up the resistance value of pin through the calibration voltage, makes the required export power supply of its output.

Description

The online dynamically continuously adjustabe out-put supply of high precision

Technical field

The utility model relates to adjustable output electric power field, specifically the online dynamically continuously adjustabe out-put supply of a kind of high precision.

Background technology

Conventional power supply chip and power module are all fixing output, or by the disposable adjustable output of outer meeting resistance.But in some environments, usually need out-put supply variable online.

The output of normal power supplies chip is open loop mode, if when running into backend electronics load change, likely do not reach the high-precision power output effect of expection.

Current a lot of electronics board, all needs different voltage to export; Conventionally need to design different power supply chip, and configure different peripheral chips, need the longer design selection time like this, and purchase, weld interval, be unfavorable for the reliability providing electronics to design.The utility model uses identical configuration circuit, can realize different voltage and export, can add Fast Electronics conceptual design, reduce the component purchase time, and be conducive to the conservative control of cost, quality.

Utility model content

For above shortcomings part in prior art, the technical problems to be solved in the utility model is to provide the online dynamically continuously adjustabe out-put supply of high precision.

The technical scheme that the utility model is adopted for achieving the above object is: the online dynamically continuously adjustabe out-put supply of a kind of high precision,

Microprocessor, connecting analog acquisition chip and digital potentiometer, for receiving the magnitude of voltage collected from analog acquisition chip, by self SPI interface configuration digital potentiometer;

Digital potentiometer, output terminal concatenation operation amplifier and power supply chip, under the configuration of microprocessor, change the resistance value of the Voltage Cortrol pin of power supply chip;

Operational amplifier, output terminal connecting analog acquisition chip and power supply chip, the voltage for gathering power supply chip arranges the magnitude of voltage corresponding to pin resistance value;

Analog acquisition chip, the magnitude of voltage that the output resistance for Real-time Collection digital potentiometer is changed out, and by SPI interface, the magnitude of voltage collected is passed to microprocessor chip in real time;

Power supply chip, arranges the resistance value of pin by adjustment voltage, make its output terminal export required out-put supply.

Described microprocessor adopts Yi Fa company STM32F103 family chip product.

Described analog acquisition chip adopts ADI company to have the AD7192 modulus conversion chip of 4 road analog acquisition passages.

Described digital potentiometer is Nonvolatile digital pot, adopts ADI company AD5235B.

Described power supply chip adopts supports 4.5V to the 36V input range of LINEAR company and the LTM8029 of 1.2V to 18V output area.

Also comprising crystal oscillator unit, connecting microprocessor, for providing system clock for microprocessor.

Described crystal oscillator unit adopts EPSON company 8MHz crystal oscillator.

Described operational amplifier adopts high precision, the low noise operational amplifier OPA2277 of TI company.

The utility model has the following advantages and beneficial effect:

1. the utility model uses identical configuration circuit, can realize different voltage and export, can add Fast Electronics conceptual design, reduce the component purchase time, and be conducive to the conservative control of cost, quality.

2. power supply export can online, dynamic, continuous setup, and power supply output accuracy can be controlled in real time;

3. can accelerate design selection process, the buying that raising original method uses multiple different electrical power chip to cause, welding quality and integrity problem.

Accompanying drawing explanation

Fig. 1 is one-piece construction block diagram of the present utility model;

Fig. 2 is circuit theory diagrams of the present utility model;

Fig. 3 is the cut-away view of digital potentiometer AD5235;

Fig. 4 is that the resistance of digital potentiometer AD5235 exports block diagram.

Embodiment

Below in conjunction with drawings and Examples, the utility model is described in further detail.

As shown in Figure 1, the utility model comprises microprocessor, analog acquisition chip, digital potentiometer, operational amplifier, power supply chip etc.

As shown in Figure 2, the utility model embodiment comprises: power supply chip U1, microprocessor U2, digital potentiometer U3, modulus conversion chip U4, operational amplifier U5, crystal oscillator Y1, electric capacity C1, C2, C3, C4, C5, C6.

Microprocessor U2 chip adopts Yi Fa company STM32F103 series of products; Modulus conversion chip U4 adopts ADI company AD7192 modulus conversion chip, and it has 4 road analog acquisition passages, 24bit sampling precision, 4.8ksps sampling rate; Digital potentiometer U3 adopts ADI company AD5235B, and it is Nonvolatile digital pot, no matter once can configure whether power down persistence configuration information, it has 1024 step adjustable extents; Power supply chip U1 adopts LINEAR company LTM8029, and it supports 4.5V to 36V input range and 1.2V to 18V output area, and can realize the current output capability of 600mA; System clock is crystal oscillator Y1, adopts EPSON company 8MHz crystal oscillator.Operational amplifier U5 adopts TI company, high precision, low noise operational amplifier OPA2277, its offset voltage 10uV, quiescent current 800uA, open-loop gain 130dB.

Microprocessor U2, by self SPI interface configuration digital potentiometer U3, makes RT, FB pin stake resistance of power supply chip U1 in the zone of reasonableness that chip handbook is arranged; According to power supply chip LTM8029 chip handbook, the resistance value required for configuration voltage exports.Use operational amplifier OPA2277, the voltage range of adjustment RT, FB pin, makes it meet modulus conversion chip AD7192 analog input threshold value.LTM8029 chip RT, FB pin voltage of modulus conversion chip AD7192 Real-time Collection after conditioning, the resistance to earth of RT, FB pin of this magnitude of voltage and corresponding power chip LTM8029; The magnitude of voltage collected, by SPI interface, is passed to microprocessor U2 by modulus conversion chip AD7192 in real time.

The concrete steps that microprocessor resolves current resistive value are:

(1) first the resistance value of power supply chip U1 plan corresponding to output voltage values is inquired according to table 1;

Table 1LTM8029 voltage output and configuration circuit relation

(2) as shown in Figure 3, use microprocessor SMT32F103 chip foundation formula (1) by SPI interface configuration digital potentiometer, realize the output of resistance value needed for power supply chip;

$R_{WB}\left(D\right)=\frac{D}{1024}\×R_{AB}+R_W---\left(1\right)$

Wherein, R _wBfor final output resistance; D is percent value; R _aBfor overall resistance; R _wfor chip room temperature resistance value.

(3) voltage of power supply adjustment pin, accesses AD7192 chip after operational amplifier, calculates the magnitude of voltage of current AD7192 input according to formula (2);

$AIN=\frac{Code\×V_{REF}}{2^N\×Gain}---\left(2\right)$

Wherein, AIN is the analog acquisition magnitude of voltage of analog acquisition chip AD7192; Code is the data value after analog acquisition chip AD7192 analog to digital conversion; VREF is the reference voltage level of analog acquisition chip AD7192; Gain is the yield value that the inside of analog acquisition chip AD7192 can be established; N is the data acquisition resolution of analog acquisition chip AD7192.

(4) after being converted by the scale-up factor of operational amplifier, can draw the magnitude of voltage of current power adjustment pin, the monitoring of this road is main to be realized, and power supply adjustment pin voltage is in power supply chip handbook allowed band;

(5) as shown in Figure 4, electric power output voltage value is introduced operation amplifier circuit AD7192 chip, the magnitude of voltage of current AD7192 input is calculated according to formula (2), current power output voltage values can be calculated after being converted by the scale-up factor of operational amplifier, after being that original target voltage values carries out closed-loop control, by regulating the resistance value of digital potentiometer, the online dynamically continuously adjustabe out-put supply of high precision can be realized.

Claims (8)

1. the online dynamically continuously adjustabe out-put supply of high precision, is characterized in that, comprising:

Microprocessor, connecting analog acquisition chip and digital potentiometer, for receiving the magnitude of voltage collected from analog acquisition chip, by self SPI interface configuration digital potentiometer;

Digital potentiometer, output terminal concatenation operation amplifier and power supply chip, under the configuration of microprocessor, change the resistance value of the Voltage Cortrol pin of power supply chip;

Operational amplifier, output terminal connecting analog acquisition chip and power supply chip, the voltage for gathering power supply chip arranges the magnitude of voltage corresponding to pin resistance value;

Analog acquisition chip, the magnitude of voltage that the output resistance for Real-time Collection digital potentiometer is changed out, and by SPI interface, the magnitude of voltage collected is passed to microprocessor chip in real time;

Power supply chip, arranges the resistance value of pin by adjustment voltage, make its output terminal export required out-put supply.

2. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, it is characterized in that, described microprocessor adopts Yi Fa company STM32F103 family chip product.

3. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, it is characterized in that, described analog acquisition chip adopts ADI company to have the AD7192 modulus conversion chip of 4 road analog acquisition passages.

4. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, it is characterized in that, described digital potentiometer is Nonvolatile digital pot, adopts ADI company AD5235B.

5. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, is characterized in that, described power supply chip adopts supports 4.5V to the 36V input range of LINEAR company and the LTM8029 of 1.2V to 18V output area.

6. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, is characterized in that, also comprises crystal oscillator unit, connecting microprocessor, for providing system clock for microprocessor.

7. the online dynamically continuously adjustabe out-put supply of high precision according to claim 6, it is characterized in that, described crystal oscillator unit adopts EPSON company 8MHz crystal oscillator.

8. the online dynamically continuously adjustabe out-put supply of high precision according to claim 1, it is characterized in that, described operational amplifier adopts high precision, the low noise operational amplifier OPA2277 of TI company.