Low ripple power supply circuit with controllable dual voltage output

Abstract

The invention discloses a low-ripple power supply circuit with controllable dual voltage output, and relates to a low-ripple power supply circuit with controllable dual voltage output. The invention solves the problems that in the process of adjusting the bias power supply voltage of a detector by an existing DAC, there are many controller interfaces, and the DAC is rarely used in harsh space environments and is expensive. The invention proposes to use two operational amplifiers with enable outputs to realize a dual voltage switching output function. The first operational amplifier is selected to output a high level or be in a high impedance state according to the high and low levels of an external control signal; the input end of the second operational amplifier is simultaneously connected to the output and the low level voltage of the first operational amplifier, so as to output two low and high level low ripple voltages according to the external control signal.

Description

Technical Field

[0001] The invention relates to a low-ripple power supply circuit with controllable dual-voltage output, and in particular to a low-ripple power supply circuit with controllable dual-voltage output for aerospace applications. Background Art

[0002] At present, when a detector with multiple working modes switches its working mode, the bias supply voltage of the detector also needs to change. In order to ensure sufficient imaging working characteristics, the working voltage fluctuation is required to be small. A simple solution is to use a digital-to-analog converter DAC to adjust the supply voltage and use an op amp to improve the power supply capacity. Using DAC to generate the required dual working voltage is convenient and flexible. On the one hand, the difficulty is that the high-precision parallel DAC occupies a large number of controller interfaces, and on the other hand, there are too few optional DACs with experience in harsh space environment flights, and they are expensive. Summary of the invention

[0003] The present invention provides a low ripple power supply circuit with controllable dual voltage output to solve the problems of a large number of controller interfaces in the existing DAC adjustment process for the bias supply voltage of the detector, and a small number of DACs used in harsh space environments and high prices.

[0004] A low ripple power supply circuit with controllable dual voltage output includes a high voltage power supply and a low voltage power supply; and also includes a first operational amplifier, a second operational amplifier, an imaging controller, a resistor R1, a resistor R2, and a resistor R3;

[0005] The negative input terminal of the first op amp is connected to the output terminal O, and the negative input terminal of the second op amp is connected to the output terminal O; the positive power supply terminal VCC of the first op amp and the second op amp is connected to VDD, and the negative power supply terminal VSS is connected to VEE;

[0006] The positive input terminal of the first op amp is connected to a high voltage power supply, and the output terminal O is connected to the positive input terminal of the second op amp via a resistor R1; the output terminal of the low voltage power supply is connected to the positive input terminal of the second op amp via a resistor R3; the output terminal O of the second op amp is connected to the detector via a resistor R2;

[0007] The enable terminal EN of the first op amp is connected to the imaging controller through a driver; the enable terminal EN of the second op amp is connected to VDD; the chip high voltage power supply is connected to VDD, and the chip low voltage power supply is connected to VEE.

[0008] Beneficial effects of the present invention:

[0009] 1. The power supply circuit of the present invention adopts a power chip and an operational amplifier that can be used in a harsh space environment, which can avoid the problem of difficult selection of a digital-to-analog converter with high radiation resistance performance index;

[0010] 2. The power supply circuit of the present invention does not use a digital-to-analog converter DAC, but uses a pin of a controller to perform high and low level control, which can reduce the consumption of controller pin resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 The circuit diagram is a low ripple power supply circuit with controllable dual voltage output. DETAILED DESCRIPTION

[0012] Combination Figure 1 The present embodiment is described, and the low ripple power supply circuit with controllable dual voltage output includes an op amp 1, an op amp 2, an imaging controller, a high voltage power supply, a low voltage power supply, a resistor R1, a resistor R2 and a resistor R3. Both op amp 1 and op amp 2 have a positive input terminal +, a negative input terminal -, an enable terminal EN, an output terminal O, a positive power supply terminal VCC and a negative power supply terminal VSS. The negative input terminal - and the output terminal O of op amp 1 and op amp 2 are connected together, the positive power supply terminal VCC is connected to VDD, and the negative power supply terminal VSS is connected to VEE. The positive input terminal of op amp 1 is connected to a high voltage power supply, and the voltage output by the high power supply is V_high. The output terminal O of amplifier 1 is connected to the positive input terminal + of amplifier 2 through resistor R1; the voltage output by the low voltage power supply is V_low, which is connected to the positive input terminal + of amplifier 2 after passing through resistor R3; the voltage Vout output by the output terminal O of amplifier 2 is sent to the detector through resistor R3; the enable terminal EN of amplifier 1 is connected to the driver, which is controlled by the imaging controller; the enable terminal EN of amplifier 2 is connected to VDD. The high voltage power supply of the chip is connected to VDD, and the low voltage power supply of the chip is connected to VEE.

[0013] In this embodiment, the low ripple power supply circuit with controllable dual voltage output includes an op amp 1, an op amp 2, an imaging controller, a high voltage power supply, a low voltage power supply, a resistor R1, a resistor R2 and a resistor R3. Both op amp 1 and op amp 2 have a positive input terminal +, a negative input terminal -, an enable terminal EN, an output terminal O, a positive power supply terminal VCC and a negative power supply terminal VSS. The negative input terminal - and the output terminal O of op amp 1 and op amp 2 are connected together, the positive power supply terminal VCC is connected to VDD, and the negative power supply terminal VSS is connected to VEE. The positive input terminal of op amp 1 is connected to a high voltage power supply, and the voltage output by the high power supply is V_high. The output terminal O of amplifier 1 is connected to the positive input terminal + of amplifier 2 through resistor R1; the voltage output by the low voltage power supply is V_low, which is connected to the positive input terminal + of amplifier 2 after passing through resistor R3; the voltage Vout output by the output terminal O of amplifier 2 is sent to the detector through resistor R3; the enable terminal EN of amplifier 1 is connected to the driver, which is controlled by the imaging controller; the enable terminal EN of amplifier 2 is connected to VDD. The high voltage power supply of the chip is connected to VDD, and the low voltage power supply of the chip is connected to VEE.

[0014] In this embodiment, the voltage Vout outputted from the output terminal O of the operational amplifier 2 through the resistor R3 reaches the detector, and the high level of Vout is equal to the voltage V_high outputted by the high voltage power supply; the low level of Vout is equal to the voltage V_low outputted by the low voltage power supply; when the voltage VDD appears at the EN terminal of the operational amplifier 1, the output voltage of Vout is V_high; when the voltage VEE appears at the EN terminal of the operational amplifier 1, the output voltage of Vout is V_low.

[0015] In this embodiment, the resistance of resistors R1 and R2 is 0 ohm; the resistance of resistor R3 is between 1k and 100k, which is required not to exceed 1 / 100 of the input resistance of op amp 1 or op amp 2;

[0016]

[0017] Where R IN is the input resistance value of the op amp;

[0018] The internal resistance R of the high voltage power supply high Less than or equal to 1 / 100 of the input resistance of the op amp; the internal resistance of the low voltage power supply is less than 1 / 100 of R3;

[0019]

[0020]

[0021] In this implementation, the value requirements of the high voltage VDD output by the chip high voltage power supply and the low voltage VEE output by the chip low voltage power supply are:

[0022]

[0023] Where V ZF_safe It is the safety voltage difference between the positive and negative power supplies of the op amp.

[0024] In this embodiment, the operational amplifier adopts AD8041 of ADI Company of the United States; the high voltage power supply, the low voltage power supply, the chip high voltage power supply and the chip low voltage power supply adopt LDO output; the imaging controller adopts FPGA of Xilinx Company; the detector adopts a planar array detector; the resistors R1, R2 and R3 adopt resistors in 0805 package; and the driver adopts a transistor circuit.

Claims

1. A low ripple power supply circuit with controllable dual voltage output, comprising a high voltage power supply and a low voltage power supply; the characteristics are: It also includes a first operational amplifier, a second operational amplifier, an imaging controller, a resistor R1, a resistor R2 and a resistor R3; The negative input terminal of the first op amp is connected to the output terminal O, and the negative input terminal of the second op amp is connected to the output terminal O; the positive power supply terminal VCC of the first op amp and the second op amp is connected to VDD, and the negative power supply terminal VSS is connected to VEE; The positive input terminal of the first op amp is connected to a high voltage power supply, and the output terminal O is connected to the positive input terminal of the second op amp via a resistor R1; the output terminal of the low voltage power supply is connected to the positive input terminal of the second op amp via a resistor R3; the output terminal O of the second op amp is connected to the detector via a resistor R2; The enable terminal EN of the first op amp is connected to the imaging controller through the driver; the enable terminal EN of the second op amp is connected to VDD; the chip high voltage power supply is connected to VDD, and the chip low voltage power supply is connected to VEE; The resistance values ​​of the resistors R1 and R2 are 0 ohms; the resistance value of the resistor R3 is between 1k and 100k, and is required not to exceed 1 / 100 of the input resistance of the first op amp or the second op amp; In the formula, is the input resistance value of the op amp.

2. The low ripple power supply circuit with controllable dual voltage output according to claim 1, characterized in that: The output terminal O of the second op amp outputs a voltage Vout to the detector via the resistor R2, wherein the high level of the voltage Vout is the same as the high voltage V_high output by the high voltage power supply; the low level of the voltage Vout is the same as the low voltage V_low output by the low voltage power supply; When the voltage VDD appears at the enable terminal EN of the first operational amplifier, the voltage Vout is the same as the voltage V_high; when the voltage VEE appears at the enable terminal EN of the first operational amplifier, the voltage Vout is the same as the voltage V_low.

3. The low ripple power supply circuit with controllable dual voltage output according to claim 1, characterized in that: The internal resistance of the high voltage power supply Less than or equal to 1 / 100 of the input resistance of the first op amp or the second op amp; internal resistance of the low voltage power supply Less than or equal to 1 / 100 of the resistance R3; ， 。 4. The low ripple power supply circuit with controllable dual voltage output according to claim 1, characterized in that: The voltage VDD of the chip high voltage power supply and the voltage VEE of the chip low voltage power supply are required to be: In the formula It is the safety voltage difference between the positive and negative power supplies of the first op amp or the second op amp.

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