Simple numerical control programmable reference voltage circuit
Through simple CNC programmable reference circuit, combined with synchronous decimal reversible counting circuit and T-type resistor network digital-to-analog conversion circuit, the problem of poor stability of the existing reference voltage circuit is solved, and high-precision adjustable reference voltage output is realized, suitable for high-quality high-quality Accuracy electronic equipment.
Patent Information
- Application Number
- CN202420641861.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-31
- Publication Date
- 2024-12-10
- Estimated Expiration
- 2034-03-31
AI Technical Summary
The existing reference voltage circuit has poor stability and cannot provide high-precision adjustable reference voltage output, limiting the stable operation of high-precision electronic devices.
It adopts a simple CNC programmable reference circuit, combined with a synchronous decimal reversible counting circuit and a T-type resistor network digital-to-analog conversion circuit, and implements an input decimal output binary through IC1 (CD40192), and uses an operational amplifier LM358 to output a stable and reliable reference voltage.
It realizes high-precision adjustable reference voltage output, improves the stability and reliability of the circuit, and is suitable for large-scale, ultra-large-scale integrated circuits and digital analog systems.
Smart Images
Figure CN222145439U_ABST
Abstract
Description
Technical field:
[0001] The utility model belongs to the technical field of sonar electronic engineering, and in particular relates to a simple digitally controlled programmable reference voltage circuit. Background technology:
[0002] In high-precision electronic devices, it is generally required to provide them with high-precision voltage output to ensure the normal and stable operation of the electronic devices.
[0003] Generally, a resistor divider can be used as a reference voltage, but it can only be used as a bias voltage for the amplifier or to provide the operating current for the amplifier. This is mainly because it has no voltage stabilization function of its own. Therefore, the stability of the output voltage is completely dependent on the stability of the power supply voltage. However, the stability of the reference voltage circuit in the prior art is poor. Utility model content:
[0004] The technical problem to be solved by the utility model is to provide a simple digitally controlled programmable reference voltage circuit. Aiming at the single output of the existing reference voltage, such a multi-group reference voltage circuit has a small volume, a simple structure, and a high reliability. It is suitable for large-scale and ultra-large-scale integrated circuits and an indispensable basic circuit module in almost all digital analog systems, and realizes a high-precision adjustable reference voltage output.
[0005] The technical solution of the utility model is to provide a simple digital control programmable reference voltage circuit, including an electrically connected synchronous decimal reversible counting circuit and a T-type resistor network digital-to-analog conversion circuit, wherein the synchronous decimal reversible counting circuit is composed as follows: the power supply is connected in series with the first resistor R1 and then connected to the UP end of IC1, the first touch switch S1 is connected in parallel with the first capacitor C1, one end of the first capacitor C1 connected in parallel is connected to the UP end of IC1, and the other end of the first capacitor C1 is grounded; the power supply is connected in series with the second resistor R2 and then connected to the DOWN end of IC1, the second touch switch S2 is connected in parallel with the second capacitor C2, one end of the second capacitor C2 connected in parallel is connected to the DOWN end of IC1, and the other end of the second capacitor C2 is grounded; one end of the third capacitor C3 is connected to the power supply, the other end of the third capacitor C3 is connected to the CLR end of IC1, one end of the third resistor R3 is connected to the CLR end of IC1, and the other end of the third resistor R3 is grounded. The setting end LD and the power supply end VDD of IC1 are connected to the positive power supply. The ground terminal GND of IC1 is grounded; the QA, QB, QC, and QD terminals of IC1 are connected to a T-type resistor network.
[0006] Preferably, the T-type resistor network digital-to-analog conversion circuit is composed as follows:
[0007] One end of the fourth resistor R4 is grounded, and the other end of the fourth resistor R4 is connected to the A connection point. The sixth resistor R6, the eighth resistor R8, the tenth resistor R10, and the twelfth resistor R12 are each connected end to end and connected in series to the inverting input terminal of the operational amplifier IC2.1. One end of the fifth resistor R5 is connected to the QA terminal of IC1, and the other end of the fifth resistor R5 is connected to the A connection point; one end of the seventh resistor R7 is connected to the QB terminal of IC1, and the other end of the seventh resistor R7 is connected to the B connection point; one end of the ninth resistor R9 is connected to the QC terminal of IC1, and the other end of the ninth resistor R9 is connected to the C connection point; one end of the eleventh resistor R11 is connected to the QD terminal of IC1, and the other end of the eleventh resistor R11 is connected to the QD terminal of IC1. One end of the overcurrent protection resistor Rf1 is connected to the inverting input terminal of the operational amplifier IC2.1, and the other end of the overcurrent protection resistor Rf1 is connected to the operational amplifier output terminal OUT1 of the operational amplifier IC2.1. The non-inverting input terminal of the operational amplifier IC2.1 is grounded. The negative power supply terminal of the operational amplifier IC2.1 is grounded. The positive power supply terminal of the operational amplifier IC2.1 is connected to VCC, wherein the A connection point is located between the fourth resistor R4 and the sixth resistor R6 connected in series, and the B connection point, the C connection point, and the D connection point are respectively located between the sixth resistor R6 and the eighth resistor R8, the eighth resistor R8 and the tenth resistor R10, and the tenth resistor R10 and the twelfth resistor R12 connected in series.
[0008] Compared with the prior art, the utility model has the following advantages:
[0009] The utility model realizes decimal input and binary output through IC1 (CD40192) synchronous decimal reversible counter, and the counting result is output from QA, QB, QC and QD terminals to the T-type resistor network digital-to-analog conversion circuit, and then outputs a stable and reliable reference voltage through the integrated operational amplifier LM358, thereby realizing high-precision adjustable reference voltage output. Description of the drawings:
[0010] Figure 1 This is a schematic diagram of a reference voltage circuit of the utility model.
[0011] Figure 2 The utility model is a schematic diagram of a synchronous decimal reversible counting circuit.
[0012] Figure 3 The figure is a schematic diagram of a T-type resistor network digital-to-analog conversion circuit of the present utility model. Specific implementation method:
[0013] The present invention will be further described below with reference to the accompanying drawings:
[0014] The utility model discloses a simple digitally controlled programmable reference voltage circuit, which comprises a synchronous decimal reversible counting circuit and a T-type resistor network digital-to-analog conversion circuit, and realizes a high-precision adjustable reference voltage output.
[0015] See also Figure 2 As shown, the +5V power supply is connected in series with the first resistor R1 and then connected to the UP terminal of IC1 (CD40192), the first touch switch S1 is connected in parallel with the first capacitor C1, one end of the first capacitor C1 is connected in parallel to the UP terminal of IC1, and the other end of the first capacitor C1 is grounded. The +5V power supply is connected in series with the second resistor R2 and then connected to the DOWN terminal of IC1, the second touch switch S2 is connected in parallel with the second capacitor C2, one end of the second capacitor C2 is connected in parallel to the DOWN terminal of IC1, and the other end of the second capacitor C2 is grounded. One end of the third capacitor C3 is connected to the +5V power supply, and the other end of the third capacitor C3 is connected to the CLR terminal of IC1. One end of the third resistor R3 is connected to the CLR terminal of IC1, and the other end of the third resistor R3 is grounded. The digital terminal LD and the power supply terminal VDD of IC1 are connected to the positive power supply 5V. The ground terminal GND of IC1 is grounded. The first touch switch S1 and the second touch switch S2 as the control unit are controlled. Each time the first touch switch S1 or the second touch switch S2 is pressed, a low level is given. If the button is not pressed, it is in a high level state. The counter outputs binary by pressing the UP / DOWN low level button. It will be cleared every time the power is turned on, and the output binary is 0000; Addition counting: When the first touch switch S1 is pressed once to send the low level to the counter UP, the output is binary 0001. Pressing once increases the value once, and so on. Pressing the ninth time will get the output binary 1001. Pressing it again will start from binary 0000; Subtraction counting: When the second touch switch S2 is pressed once to send the high level to the counter DOWN, the output is binary 1001. Pressing the button once decreases the value once. Pressing the button the ninth time will get the output binary 0001. Pressing it again will start from binary 0000. As shown in Table 1 below:
[0016] Table 1
[0017] Decimal QD QC QB QA 0 0 0 0 0 1 0 0 0 1 2 0 0 1 0 3 0 0 1 1 4 0 1 0 0 5 0 1 0 1 6 0 1 1 0 7 0 1 1 1 8 1 0 0 0 9 1 0 0 1
[0018] In addition, the QA, QB, QC, and QD terminals of IC1 are connected to a T-type resistor network.
[0019] See also Figure 3 , the T-type resistor network digital-to-analog conversion circuit is composed as follows:
[0020] One end of the fourth resistor R4 is grounded, and the other end of the fourth resistor R4 is connected to the A connection point. The sixth resistor R6, the eighth resistor R8, the tenth resistor R10, and the twelfth resistor R12 are each connected end to end and connected in series to the inverting input terminal of the operational amplifier IC2.1. One end of the fifth resistor R5 is connected to the QA terminal of IC1, and the other end of the fifth resistor R5 is connected to the A connection point; one end of the seventh resistor R7 is connected to the QB terminal of IC1, and the other end of the seventh resistor R7 is connected to the B connection point; one end of the ninth resistor R9 is connected to the QC terminal of IC1, and the other end of the ninth resistor R9 is connected to the C connection point; one end of the eleventh resistor R11 is connected to the QD terminal of IC1, and the other end of the eleventh resistor R11 is connected to the QD terminal of IC1. One end of the overcurrent protection resistor Rf1 is connected to the inverting input terminal of the operational amplifier IC2.1, and the other end of the overcurrent protection resistor Rf1 is connected to the operational amplifier output terminal OUT1 of the operational amplifier IC2.1. The non-inverting input terminal of the operational amplifier IC2.1 is grounded. The negative power supply terminal of the operational amplifier IC2.1 is grounded. The positive power supply terminal of the operational amplifier IC2.1 is connected to VCC, wherein the A connection point is located between the fourth resistor R4 and the sixth resistor R6 connected in series, and the B connection point, the C connection point, and the D connection point are respectively located between the sixth resistor R6 and the eighth resistor R8, the eighth resistor R8 and the tenth resistor R10, and the tenth resistor R10 and the twelfth resistor R12 connected in series.
[0021] See also Figure 1 , Figure 2 , Figure 3 , output reference voltage method, when QA, QB, QC, QD are high level, use U REF Indicates that when QD is high level U REF , QC, QB, QA are low level, two 2R on the left side of A connection point are connected in parallel to get R, and connected in series with R on the right side of A connection point to get 2R, U REF The current passing through 2R is divided into two through the D connection point, and the current flowing to both sides is I / 2. The current flowing through the twelfth resistor R12 as the load resistor is IL=I / 2. The resistors on both sides of the D connection point are connected in parallel to obtain R, and I=U REF / 3R.
[0022] When QC is high level U REF , QD, QB, QA are low level, and the current I flowing through the twelfth resistor R12 L =I / 4,I=U REF / 3R. And so on, when QB and QA enter high level U REF , the current flowing through the I3 and I4 branches is I=U REF / 3R, where the current flowing through the twelfth resistor R12 is I / 8, I / 16. According to the superposition principle, the current flowing through the twelfth resistor R12 can be written as I L for:
[0023] IL=(1 / 2QD+1 / 4QC+1 / 8QB+1 / 16QA)I
[0024] =UREF / 3R(1 / 2QD+1 / 4QC+1 / 8QB+1 / 16QA)
[0025] RF=3R, then UO=IL*RF=-If*RF; IL=IΣ=-If
[0026] This circuit works in the linear region. The input to the reverse input terminal of the operational amplifier meets the short circuit requirement. The non-inverting input terminal is grounded and the reverse input terminal is virtually grounded, which is equivalent to both the non-inverting input terminal and the reverse input terminal being grounded.
[0027] -UO=If*RF=UREF(1 / 2QD+1 / 4QC+1 / 8QB+1 / 16QA)
[0028] T-Network Resistor Output Voltage:
[0029] -UO=IΣ*RF=UREF(1 / 2QD+1 / 4QC+1 / 8QB+1 / 16QA)
[0030] ,UREF=5V, and 9 groups of reference voltages are calculated as shown in Table 2 below:
[0031] Table 2
[0032] QD QC QB QA UO 0 0 0 0 0 0 1 0 0 0 1 -0.3125V 2 0 0 1 0 -0.6250V 3 0 0 1 1 -0.9375V 4 0 1 0 0 -1.2500V 5 0 1 0 1 -1.5625V
[0033] The 9 groups of voltages measured in the actual application circuit are shown in Table 3 below:
[0034] Table 3
[0035] QD QC QB QA UO 0 0 0 0 0 0 1 0 0 0 1 -0.313V 2 0 0 1 0 -0.625V 3 0 0 1 1 -0.938V 4 0 1 0 0 -1.250V 5 0 1 0 1 -1.563V 6 0 1 1 0 -1.875V 7 0 1 1 1 -2.188V 8 1 0 0 0 -2.500V 9 1 0 0 1 -2.813V
[0036] After experimental testing, a simple digitally controlled programmable reference voltage circuit shown in this embodiment, including a synchronous decimal reversible counting circuit and a T-type resistor network digital-to-analog conversion circuit, achieves a high-precision adjustable reference voltage output.
[0037] The cooling device of the utility model has high safety protection, has the ability of early alarm of cooler leakage fault, and greatly increases the service life of the cooler through filtering and drainage functions, and is also very convenient for maintenance.
Claims
1. A simple digitally controlled programmable reference voltage circuit, characterized in that: The invention comprises an electrically connected synchronous decimal reversible counting circuit and a T-type resistor network digital-to-analog conversion circuit, wherein the synchronous decimal reversible counting circuit is composed as follows: a power supply is connected in series with a first resistor R1 and then connected to an UP terminal of IC1, a first touch switch S1 is connected in parallel with a first capacitor C1, one end of the first capacitor C1 connected in parallel is connected to the UP terminal of IC1, and the other end of the first capacitor C1 is grounded; a power supply is connected in series with a second resistor R2 and then connected to a DOWN terminal of IC1, a second touch switch S2 is connected in parallel with a second capacitor C2, one end of the second capacitor C2 connected in parallel is connected to the DOWN terminal of IC1, and the other end of the second capacitor C2 is grounded; one end of a third capacitor C3 is connected to the power supply, and the other end of the third capacitor C3 is connected to the CLR terminal of IC1, one end of a third resistor R3 is connected to the CLR terminal of IC1, and the other end of the third resistor R3 is grounded, a number setting terminal LD and a power supply terminal VDD of IC1 are connected to a positive power supply, and a ground terminal GND of IC1 is grounded; and QA, QB, QC, and QD terminals of IC1 are connected to the T-type resistor network.
2. The simple digitally controlled programmable reference voltage circuit according to claim 1, characterized in that: The T-type resistor network digital-to-analog conversion circuit is composed as follows: One end of the fourth resistor R4 is grounded, and the other end of the fourth resistor R4 is connected to the A connection point. The sixth resistor R6, the eighth resistor R8, the tenth resistor R10, and the twelfth resistor R12 are each connected end to end and connected in series to the inverting input terminal of the operational amplifier IC2.
1. One end of the fifth resistor R5 is connected to the QA terminal of IC1, and the other end of the fifth resistor R5 is connected to the A connection point; one end of the seventh resistor R7 is connected to the QB terminal of IC1, and the other end of the seventh resistor R7 is connected to the B connection point; one end of the ninth resistor R9 is connected to the QC terminal of IC1, and the other end of the ninth resistor R9 is connected to the C connection point; one end of the eleventh resistor R11 is connected to the QD terminal of IC1, and the other end of the eleventh resistor R11 is connected to the QD terminal of IC1. One end of the overcurrent protection resistor Rf1 is connected to the inverting input terminal of the operational amplifier IC2.1, and the other end of the overcurrent protection resistor Rf1 is connected to the operational amplifier output terminal OUT1 of the operational amplifier IC2.
1. The non-inverting input terminal of the operational amplifier IC2.1 is grounded. The negative power supply terminal of the operational amplifier IC2.1 is grounded. The positive power supply terminal of the operational amplifier IC2.1 is connected to VCC, wherein the A connection point is located between the fourth resistor R4 and the sixth resistor R6 connected in series, and the B connection point, the C connection point, and the D connection point are respectively located between the sixth resistor R6 and the eighth resistor R8, the eighth resistor R8 and the tenth resistor R10, and the tenth resistor R10 and the twelfth resistor R12 connected in series.
3. The simple digitally controlled programmable reference voltage circuit according to claim 1, characterized in that: IC1 is CD40192.