CN1474502A

CN1474502A - Circuit block for generating low ripple APD bias voltage

Info

Publication number: CN1474502A
Application number: CNA031418201A
Authority: CN
Inventors: 李和祥; 陈修亮; 周春源; 吴光; 曾和平
Original assignee: East China Normal University
Current assignee: East China Normal University
Priority date: 2003-07-25
Filing date: 2003-07-25
Publication date: 2004-02-11
Anticipated expiration: 2023-07-25
Also published as: CN1474502B

Abstract

This invention relates to a privacy system especially relates to circuit module capable of generating APD bias voltage realizing low ripple high voltage power supply of APD single photon detectors in quantum privacy system, the said module is composed of oscillation booster circuit and parallel regulation circuit, among which, the oscillation booster circuit includes a filtration circuit, a multiple resonance circuit and a booster circuit effectively reducing the ripple voltage amplitude of an output voltage.

Description

Produce the circuit module of low ripple APD bias voltage

Technical field

The present invention relates to the secure communication class, particularly relate to a kind of circuit module that can produce the APD bias voltage, realize high voltage supply the low ripple of APD single-photon detector in the quantum secret communication system.

Background technology

Quantum secret communication is based on the communication of light quantum, information loads on the single photon, and transmit by single photon, unknown quantum state can not be cloned, measure quantum and can change quantum state, the listener-in just can not obtain communication information and not be found like this, and therefore in quantum secret communication, single photon detection has very important effect.The single photon detection device that uses in the quantum secret communication system mainly is an avalanche photo diode (APD), but APD need add tens volts bias voltage when work.The size of ripple directly affects APD what of dark counts when surveying on the bias voltage, and along with the increase of dark counts, the error rate of detector also can become greatly, directly influences the performance of whole quantum secret communication system.Usually use the ME7105 power supply chip to produce bias voltage in the quantum secret communication system, the bias voltage that this power supply chip produces has 20 millivolts ripple.

Summary of the invention

The objective of the invention is provides a kind of circuit module that can produce the APD bias voltage according to above-mentioned the deficiencies in the prior art part, and this module can be transformed into 5 volts of direct voltages the low current about 40 volts, the high pressure of low ripple.

The object of the invention realizes being finished by following technical scheme:

The present invention mainly is made up of oscillation step-up circuit and shunt regulating circuit.

Oscillation step-up circuit is by inductance L 1, L2, capacitor C 1, C2, C3, C4, C5, C8, resistance R 1, R3, R4, diode D1, D2, triode Q2 and one 555 integrated circuit are formed, and wherein L1 and C1, C2 form filter circuit, are connected with L2 and 555 integrated circuits respectively again; R1 one end is connected with L1, and an other end is connected with R3, D2,555 integrated circuits, connects C8, C3 again and forms multi-resonant oscillating circuit; The output of this oscillating circuit is connected with C4 with the R4 of parallel connection, is connected with Q2, and forms booster circuit with L2, D1, C5.

Resistance R 2 one ends link to each other with D1 in the above-mentioned booster circuit, and the collector electrode of Q3, Q4 in an other end and the shunt regulating circuit and the emitter of Q1 link to each other.

Shunt regulating circuit is by triode Q1, Q3, Q4, and resistance R 5, R6, R7, R8 and capacitor C 6, C7 form, and wherein the base stage of Q3 is connected with the emitter of Q4, again by R5 ground connection; The base stage of Q4 links to each other with the collector electrode of Q1, again by R6 and C6 ground connection in parallel; The base stage of Q1 is connected on the bleeder circuit of R7 and R8 composition, crosses C7 output at last.

Advantage of the present invention is, and is simple in structure, cheap, effectively reduced the ripple voltage amplitude of output voltage, can reduce the dark counts of APD.

Summary of drawings

Accompanying drawing 1 produces the circuit theory diagrams of low ripple APD bias voltage for the present invention;

Accompanying drawing 2 is the present invention's 555 integrated circuits output pulse 1,2 oscillograms;

Accompanying drawing 3 is an embodiment of the invention circuit diagram;

Concrete technical scheme

Feature of the present invention and other correlated characteristic are described in further detail by embodiment below in conjunction with accompanying drawing, so that technical staff's of the same trade understanding:

As Figure 1-3, present embodiment has been realized 50 volts of high pressure outputs of 2 millivolts of ripples, and the components and parts of use are as follows:

L1：200uH、L2：1mH；

D1：1N4148、D2：MA150；

Q1：A1015、Q2：D1991、Q3：C1627、C4：C1815；

C1：220uf、C2：0.1uF、C3：0.01uF、C4：4700pF、C5：0.1uF、

C6：10uF/63V、C7：0.47uF、C8：4700pF；

R1：1.5kΩ、R2：10kΩ、R3：1kΩ、R4：3.3kΩ、R5：56kΩ、R6：120kΩ、

R7：100kΩ、R8：220kΩ；

555 integrated circuits: NE555;

Present embodiment mainly is made up of oscillation step-up circuit and shunt regulating circuit.

Oscillation step-up circuit is by inductance L 1, L2, capacitor C 1, C2, C3, C4, C5, C8, resistance R 1, R3, R4, diode D1, D2, triode Q2 and one 555 integrated circuit are formed, wherein 5 volts of power supplys are input to 555 integrated circuits then by the filter circuit filtering that inductance L 1 and capacitor C 1, C2 form; Via the multi-resonant oscillating circuit that 555 integrated circuits and R1, R3, D2, C8 form, output pulse 1 as shown in Figure 2; After this pulse becomes as shown in Figure 2 pulse 2 through the accelerating circuit of being made up of R4, C4, promotion triode Q2.When pulse 2 is high level, triode Q2 conducting, this moment, D1 instead ended inductance L 2 accumulation energies partially; When pulse 2 became low level, triode Q2 ended, and at this moment can produce nearly 100 volts back-emf at inductance L 2 two ends, and this high voltage makes diode D1 conducting, and inductance L 2 releases energy, and capacitor C 5 is charged.When pulse 2 once more during high level, triode Q2 conducting again, D1 is partially anti-again, and the charging voltage on the C5 is by 2 pairs of load discharges of resistance R, because the Q2 turn-off time is very short, so the voltage at C5 two ends can reach about 80 volts.In the oscillator that 555 integrated circuits are formed, the numerical value that changes resistance R 1, R3 and capacitor C 8 can change the frequency and the duty ratio of output pulse, thereby can control the conducting of triode Q2 and the time scale of ending, and then changes the size of C5 both end voltage.

Shunt regulating circuit is by triode Q1, Q3, Q4, and resistance R 5, R6, R7, R8 and capacitor C 6, C7 form.In this circuit, utilized this PN junction good stabilized voltage characteristic of triode Q1 base stage (b) with emitter (e), finally realize the purpose of voltage stabilizing.Ratio by changing R7 and R8 is to change the resistance R between triode Q1 emitter (e) and the collector electrode (c) _CeThereby, make the R of Q4, Q3 _CeChange, change the resistance of resistance R 7 just can be regulated output voltage in a big way size like this, finally through C7 filtering output, ripple is in the 2-10 millivolt for this voltage.

Claims

1, a kind of circuit module that produces low ripple APD bias voltage is characterized in that mainly being made up of oscillation step-up circuit and shunt regulating circuit, and wherein oscillation step-up circuit comprises filter circuit, multi-resonant oscillating circuit, booster circuit.

2, a kind of circuit module that produces low ripple APD bias voltage according to claim 1, it is characterized in that described oscillation step-up circuit is by inductance L 1, L2, capacitor C 1, C2, C3, C4, C5, C8, resistance R 1, R3, R4, diode D1, D2, triode Q2 and one 555 integrated circuit are formed, wherein L1 and C1, C2 forms filter circuit, be connected with L2 and 555 integrated circuits respectively, R1 one end is connected with L1 again, an other end and R3, D2,555 integrated circuits connect, connect C8 again, C3 forms multi-resonant oscillating circuit, the output of this oscillating circuit is connected with C4 with the R4 of parallel connection, is connected with Q2 again, and and L2, D1, C5 forms booster circuit.

3, a kind of circuit module that produces low ripple APD bias voltage according to claim 1, it is characterized in that described shunt regulating circuit is by triode Q1, Q3, Q4, resistance R 5, R6, R7, R8 and capacitor C 6, C7 form, wherein the base stage of Q3 is connected with the emitter of Q4, again by R5 ground connection; The base stage of Q4 links to each other with the collector electrode of Q1, again by R6 and C6 ground connection in parallel; The base stage of Q1 is connected on the bleeder circuit of R7 and R8 composition, crosses C7 output at last.

4, a kind of circuit module that produces low ripple APD bias voltage according to claim 1, it is characterized in that being connected with between described oscillation step-up circuit and the shunt regulating circuit resistance R 2, the one end links to each other with D1 in the oscillation step-up circuit, and the collector electrode of Q3, Q4 in an other end and the shunt regulating circuit and the emitter of Q1 link to each other.