High-stability reference voltage source with low initial error

Abstract

The utility model discloses a high-stability reference voltage source with low initial error, which comprises a voltage reference chip U1, a pin 1 and a pin 2 of the voltage reference chip U1 are electrically connected and are electrically connected with one end of a capacitor C1, a pin 2 of the voltage reference chip U1 is electrically connected with one end of a resistor R4, and the other end of the resistor R4 is electrically connected with the other end of the capacitor C1. A pin 2 of the voltage reference chip U1 and one end of the resistor R4 are electrically connected with the same anti-static circuit, and a pin 3 of the voltage reference chip U1 is grounded. According to the utility model, the resistor R2 is matched with the voltage stabilizer LM, so that the output voltage can be stabilized, the high-stability voltage with low initial error can be further output, the electrostatic clamp can be effectively pressed within a specified range through the arrangement of the anti-static circuit, and an effective anti-static effect is achieved; and the influence of static electricity on external electric elements can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of reference voltage sources, in particular to a high-stability reference voltage source with low initial error. Background Art

[0002] Reference voltage sources are widely used in analog and integrated circuits, and their accuracy and stability have an important impact on the performance of the entire system. The existing reference voltage sources have low stability. In addition, when the voltage output by the reference voltage source is transmitted to an external electrical component, the electrical component can absorb or release electrons, which will cause an imbalance in charge and generate static electricity. Considering the low stability and lack of anti-static function of the reference voltage source in the above-mentioned prior art, we propose a high-stability reference voltage source with low initial error. Utility Model Content

[0003] The utility model aims to solve the shortcomings in the prior art and proposes a high-stability reference voltage source with low initial error.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] A high-stability reference voltage source with low initial error includes a voltage reference chip U1, wherein pin 1 and pin 2 of the voltage reference chip U1 are electrically connected and are electrically connected to one end of a capacitor C1, pin 2 of the voltage reference chip U1 is electrically connected to one end of a resistor R4, pin 2 of the voltage reference chip U1 and one end of the resistor R4 are electrically connected to the same anti-static circuit, pin 3 of the voltage reference chip U1 is grounded, the other end of the capacitor C1 is electrically connected to the positive electrode of a diode D2, the negative electrode of the diode D1 and one end of the capacitor C2, the negative electrode of the diode D2 and the resistor R4 The other end of the resistor R4 is also electrically connected to the pin 3 of the voltage regulator LM, the pin 2 of the voltage regulator LM is electrically connected to the cathode of the diode D1, the pin 5 of the voltage regulator LM is electrically connected to one end of the resistor R2, the other end of the resistor R2 is electrically connected to the power supply voltage VCC, the pin 4 of the voltage regulator LM is electrically connected to one end of the resistor R1, the other end of the resistor R1 is grounded, the pin 4 and pin 3 of the voltage regulator LM are electrically connected to the same resistor R3, the pin 5 of the voltage regulator LM is electrically connected to the other end of the capacitor C2, and the anode of the diode D1 is grounded.

[0006] Preferably, the anti-static circuit includes a diode D3 and a diode D4, the cathode of the diode D3 and the cathode of the diode D4 are both electrically connected to pin 2 of the voltage reference chip U1, the anode of the diode D3 and the anode of the diode D4 are electrically connected to the same resistor R5, one end of the resistor R5 is electrically connected to one end of the capacitor C3 and the cathode of the diode D5, the other end of the capacitor C3 is grounded, the two ends of the resistor R5 are connected in parallel with the capacitor C4, the other end of the resistor R5 and the anode of the diode D4 are electrically connected to the cathode of the same diode D6, the other end of the resistor R5 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 is grounded, and the anode of the diode D5 and the anode of the diode D6 are both electrically connected to the output end of the anti-static circuit.

[0007] Preferably, when the power supply voltage VCC changes by 1V, the operating current of the voltage reference chip U1 changes by 1 / R2=0.0000005A=0.5uA, wherein the resistor R2 is a resistor with a huge resistance.

[0008] Preferably, the diode D3, the diode D4, the diode D5 and the diode D6 are all ESD diodes having clamping characteristics.

[0009] Preferably, the ground wires connected to the capacitors C3 and C5 are both large ground wires.

[0010] Preferably, the model of the voltage reference chip U1 is AZ431AN-ATRE1, and the model of the voltage regulator LM is LM358M.

[0011] Compared with the existing technology, the beneficial effects of the utility model are:

[0012] 1. Through the combination of resistors R1, R2 and the voltage regulator LM, when the supply voltage VCC changes very little, the change of the working current is negligible, and thus the voltage output by the voltage reference chip U1 is a highly stable voltage with low initial error;

[0013] 2. Through the diode D3, the diode D4, the diode D5, the diode D6 and the ground wire connected to the capacitor C3 and the capacitor C5, the static electricity can be effectively clamped within the specified range, achieving an effective anti-static effect, and effectively reducing the impact of static electricity on external electrical components;

[0014] The utility model can stabilize the output voltage through the setting of the resistor R2 and the voltage stabilizer LM, and then can output a high stable voltage with low initial error. Through the setting of the anti-static circuit, the static electricity can be effectively clamped within a specified range, achieving an effective anti-static effect, and can effectively reduce the impact of static electricity on external electrical components. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1A circuit diagram of a high-stability reference voltage source with low initial error proposed by the utility model;

[0016] Figure 2 The utility model discloses a circuit diagram of an anti-static circuit in a high-stability reference voltage source with low initial error. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0018] Reference Figure 1-2 A high-stability reference voltage source with low initial error includes a voltage reference chip U1, the model of the voltage reference chip U1 is AZ431AN-ATRE1, pin 1 of the voltage reference chip U1 is electrically connected to pin 2, and is electrically connected to one end of a capacitor C1, pin 2 of the voltage reference chip U1 is electrically connected to one end of a resistor R4, pin 2 of the voltage reference chip U1 and one end of the resistor R4 are electrically connected to the same anti-static circuit, pin 3 of the voltage reference chip U1 is grounded, the other end of the capacitor C1 is electrically connected to the positive electrode of a diode D2, the negative electrode of the diode D1 and one end of the capacitor C2, the negative electrode of the diode D2 is electrically connected to the other end of the resistor R4, and the other end of the resistor R4 is also electrically connected to the voltage regulator LM Pin 3, the model of the voltage regulator LM is LM358M, the pin 2 of the voltage regulator LM is electrically connected to the negative electrode of the diode D1, the pin 5 of the voltage regulator LM is electrically connected to one end of the resistor R2, and the other end of the resistor R2 is electrically connected to the power supply voltage VCC, wherein the working current of the voltage reference chip U1 changes by 1 / R2=0.0000005A=0.5uA for every 1V change in the power supply voltage VCC, wherein the resistor R2 is a resistor with a huge resistance value, the pin 4 of the voltage regulator LM is electrically connected to one end of the resistor R1, and the other end of the resistor R1 is grounded, the pin 4 and pin 3 of the voltage regulator LM are electrically connected to the same resistor R3, the pin 5 of the voltage regulator LM is electrically connected to the other end of the capacitor C2, and the positive electrode of the diode D1 is grounded;

[0019] The anti-static circuit includes a diode D3 and a diode D4, the cathode of the diode D3 and the cathode of the diode D4 are both electrically connected to pin 2 of the voltage reference chip U1, the anode of the diode D3 and the anode of the diode D4 are electrically connected to the same resistor R5, one end of the resistor R5 is electrically connected to one end of the capacitor C3 and the cathode of the diode D5, the other end of the capacitor C3 is grounded, the two ends of the resistor R5 are connected in parallel with the capacitor C4, the other end of the resistor R5 and the anode of the diode D4 are electrically connected to the cathode of the same diode D6, the other end of the resistor R5 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 is grounded, and the ground wires connected to the capacitors C3 and C5 are both large ground wires , static electricity can be introduced into the earth, the positive pole of diode D5 and the positive pole of diode D6 are electrically connected to the output end of the anti-static circuit, wherein diode D3, diode D4, diode D5 and diode D6 are all ESD diodes, which have clamping characteristics. When static electricity is discharged, the static electricity peak voltage will be clamped within a specified range by the ESD diode; the utility model can stabilize the output voltage through the setting of resistor R2 and the regulator LM, and then can output a high-stability voltage with low initial error. Through the setting of the anti-static circuit, static electricity can be effectively clamped within a specified range, achieving an effective anti-static effect, and can effectively reduce the impact of static electricity on external electrical components.

[0020] Working principle: During use, when the power supply voltage VCC enters the voltage regulator LM through the resistors R1 and R2, the voltage regulator LM will stabilize the voltage in the circuit. In addition, since the resistor R2 is a resistor with a huge resistance value, the non-inverting input terminal of its operational amplifier obtains an initial voltage. Then, when the voltage is input to the voltage reference chip U1, when the power supply voltage VCC changes very little, the change of the working current is negligible, and then the voltage output by the voltage reference chip U1 is a highly stable voltage with a low initial error;

[0021] When the voltage is output and flows through diode D3 and diode D4, since diode D3 and diode D4 are both ESD diodes, they have clamping characteristics. When static electricity is discharged, the static electricity peak voltage will be clamped within a specified range by the ESD diode, thereby ensuring the stability of the rear chip. At the same time, in conjunction with the ground wire connected to capacitor C3 and capacitor C5, static electricity can be introduced into the ground. At the same time, in conjunction with diode D5 and diode D6, the static electricity peak voltage can also be clamped within a specified range, further achieving an anti-static effect, which can effectively reduce the impact of static electricity on external electrical components.

[0022] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A high stability reference voltage source with low initial error, comprising a voltage reference chip U1, characterized in that: Pin 1 of the voltage reference chip U1 is electrically connected to pin 2, and is electrically connected to one end of a capacitor C1. Pin 2 of the voltage reference chip U1 is electrically connected to one end of a resistor R4. Pin 2 of the voltage reference chip U1 and one end of the resistor R4 are electrically connected to the same anti-static circuit. Pin 3 of the voltage reference chip U1 is grounded. The other end of the capacitor C1 is electrically connected to the positive electrode of a diode D2, the negative electrode of the diode D1, and one end of the capacitor C2. The negative electrode of the diode D2 is electrically connected to the other end of the resistor R4. The other end is also electrically connected to pin 3 of the voltage regulator LM, pin 2 of the voltage regulator LM is electrically connected to the cathode of the diode D1, pin 5 of the voltage regulator LM is electrically connected to one end of the resistor R2, the other end of the resistor R2 is electrically connected to the power supply voltage VCC, pin 4 of the voltage regulator LM is electrically connected to one end of the resistor R1, the other end of the resistor R1 is grounded, pin 4 and pin 3 of the voltage regulator LM are electrically connected to the same resistor R3, pin 5 of the voltage regulator LM is electrically connected to the other end of the capacitor C2, and the anode of the diode D1 is grounded.

2. A high stability reference voltage source with low initial error according to claim 1, characterized in that: The anti-static circuit includes a diode D3 and a diode D4, the cathode of the diode D3 and the cathode of the diode D4 are both electrically connected to pin 2 of the voltage reference chip U1, the anode of the diode D3 and the anode of the diode D4 are electrically connected to the same resistor R5, one end of the resistor R5 is electrically connected to one end of the capacitor C3 and the cathode of the diode D5, the other end of the capacitor C3 is grounded, the two ends of the resistor R5 are connected in parallel with the capacitor C4, the other end of the resistor R5 and the anode of the diode D4 are electrically connected to the cathode of the same diode D6, the other end of the resistor R5 is electrically connected to one end of the capacitor C5, the other end of the capacitor C5 is grounded, and the anode of the diode D5 and the anode of the diode D6 are both electrically connected to the output end of the anti-static circuit.

3. A high stability reference voltage source with low initial error according to claim 2, characterized in that: When the power supply voltage VCC changes by 1V, the operating current of the voltage reference chip U1 changes by 1 / R2=0.0000005A=0.5uA, wherein the resistor R2 is a resistor with a huge resistance.

4. A high stability reference voltage source with low initial error according to claim 2, characterized in that: The diode D3 , the diode D4 , the diode D5 and the diode D6 are all ESD diodes having clamping characteristics.

5. A high stability reference voltage source with low initial error according to claim 2, characterized in that: The ground wires connected to the capacitors C3 and C5 are both large ground wires.

6. A high stability reference voltage source with low initial error according to claim 1, characterized in that: The model of the voltage reference chip U1 is AZ431AN-ATRE1, and the model of the voltage regulator LM is LM358M.

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