Broadband photoelectric detection device based on transimpedance circuit

Abstract

The utility model relates to the technical field of photoelectric detectors, in particular to a broadband photoelectric detection device based on a transimpedance circuit, which comprises a photodiode D1, a photodiode D2, a transimpedance operational amplifier U1 and a current feedback amplifier U2. The cathode of the photodiode D1 is connected with the anode of the power supply, and the anode is connected with the cathode of the power supply through the photodiode D2; the anode of the photodiode D1 is also connected with the inverting input end of the transimpedance operational amplifier U1; the feedback resistor R1 and the feedback capacitor C1 are connected in parallel and then are connected between the output end and the inverted input end of the transimpedance operational amplifier U1; the output end of the transimpedance operational amplifier U1 is connected with the non-inverting input end of the current feedback amplifier U2 through a blocking capacitor C2 and a balancing resistor R3, a resistor R5 is arranged between the inverting input end and the feedback end of the current feedback amplifier U2, and the inverting input end of the current feedback amplifier U2 is grounded through a resistor R4; and the output end of the current feedback amplifier U2 is connected with the impedance matching resistor R6. The antenna is simple in structure and high in bandwidth.

Description

Technical Field

[0001] This utility model relates to the field of photodetector technology, and in particular to a broadband photodetector device based on a transimpedance circuit. Background Technology

[0002] Photoelectric detection technology plays a crucial role in quantum optics and quantum information experimental systems, and is widely used in experiments such as noise measurement of squeezed and entangled states, quantum state reconstruction, and quantum key distribution. Currently, most photodetectors employ typical transimpedance amplifier circuit structures, which suffer from a trade-off between bandwidth, gain, and signal-to-noise ratio, as well as low integration density. Currently, cascaded two- or multi-stage amplifier structures are commonly used to improve bandwidth. However, while cascaded transimpedance circuits increase bandwidth, it is still limited by the gain-bandwidth product of the amplifier itself. Utility Model Content

[0003] In order to effectively increase the bandwidth of broadband photodetectors, this invention overcomes the shortcomings of the existing technology and the technical problem to be solved is: to provide a broadband photodetector based on a transimpedance circuit.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a broadband photoelectric detection device based on a transimpedance circuit, comprising: photodiode D1, photodiode D2, transimpedance operational amplifier U1, and current feedback amplifier U2; the cathode of photodiode D1 is connected to the positive terminal of the power supply, the anode of photodiode D1 is connected to the cathode of photodiode D2, and the anode of photodiode D2 is connected to the negative terminal of the power supply; the anode of photodiode D1 is also connected to the inverting input terminal of transimpedance operational amplifier U1;

[0005] One end of the feedback resistor R1 is connected in parallel with the feedback capacitor C1, and the other end is connected to the output terminal of the transimpedance operational amplifier U1. The other end is connected to the inverting input terminal of the transimpedance operational amplifier U1, and the non-inverting input terminal of the transimpedance operational amplifier U1 is grounded.

[0006] The output of the transimpedance operational amplifier U1 is connected to the non-inverting input of the current feedback amplifier U2 through the DC blocking capacitor C2 and the balancing resistor R3. A resistor R5 is set between the inverting input and the feedback terminal of the current feedback amplifier U2, and the inverting input is grounded through the resistor R4. The output of the current feedback amplifier U2 is connected through the impedance matching resistor R6.

[0007] The broadband photodetector based on a transimpedance circuit further includes: resistors R7 and R8; the cathode of photodiode D1 is connected to the positive terminal of the power supply after series resistor R7, and the anode of photodiode D2 is connected to the negative terminal of the power supply after series resistor R8.

[0008] The wideband photoelectric detection device based on the trans-impedance circuit further comprises capacitors C3, C4, C10 and C15, and the two ends of the resistor R7 are connected to the ground through the capacitors C3 and C4 respectively, and the two ends of the resistor R8 are connected to the ground through the capacitors C10 and C15 respectively.

[0009] The wideband photoelectric detection device based on the trans-impedance circuit further comprises a resistor R9 and a capacitor C5, and the non-inverting input terminal of the trans-impedance operational amplifier U1 is connected to the ground through the parallelly connected capacitor C5 and resistor R9.

[0010] The positive power input terminal of the trans-impedance operational amplifier U1 is connected to the ground through a first filter circuit composed of the parallelly connected capacitor C8 and capacitor C11, the negative power input terminal of the trans-impedance operational amplifier U1 is connected to the ground through a second filter circuit composed of the parallelly connected capacitor C9 and capacitor C12, the positive power input terminal of the current feedback type amplifier U2 is connected to the ground through a third filter circuit composed of the parallelly connected capacitor C6 and capacitor C7, and the negative power input terminal of the current feedback type amplifier U2 is connected to the ground through a fourth filter circuit composed of the parallelly connected capacitor C13 and capacitor C14.

[0011] The positive power input terminal and the negative power input terminal of the trans-impedance operational amplifier U1 are connected to +5V DC voltage and -5V DC voltage respectively, and the positive power input terminal and the negative power input terminal of the current feedback type amplifier U2 are connected to +5V DC voltage and -5V DC voltage respectively.

[0012] The cathode of the photodiode D1 is connected to +5V DC voltage, and the anode of the photodiode D2 is connected to -5V DC voltage.

[0013] The models of the photodiode D1 and the photodiode D2 are FD150, the model of the trans-impedance operational amplifier U1 is OPA847, and the model of the current feedback type amplifier U2 is AD8000.

[0014] The wideband photoelectric detection device based on the trans-impedance circuit further comprises an SMA connector J1, the output terminal of the current feedback type amplifier U2 is connected to the pin 5 of the SMA connector J1 through an impedance matching resistor R6, and the pins 1-4 of the SMA connector J1 are connected to the ground.

[0015] Compared with the prior art, the wideband photoelectric detection device based on the trans-impedance circuit has the following beneficial effects:

[0016] The utility model provides a kind of wideband photoelectric detection device based on transimpedance circuit, by adding current feedback amplifier as weak signal secondary amplification circuit in the output terminal of operational amplifier, since the current feedback amplifier used in the utility model is not restricted by gain bandwidth product when amplifying, therefore, the utility model can effectively amplify weak signal, improve the bandwidth of photoelectric detection device, provide guarantee for the wide bandwidth of photoelectric detection device;When the current feedback amplifier with 1.5GHz working bandwidth is selected, the working bandwidth of detection device finally obtained can reach 400MHz, signal-to-noise ratio can reach 20dB, it is simple in structure, low in cost, good in performance. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a kind of wideband photoelectric detection device based on transimpedance circuit for the utility model embodiment one circuit structure schematic diagram;

[0018] Figure 2 It is a kind of wideband photoelectric detection device based on transimpedance circuit for the utility model embodiment two circuit structure schematic diagram. DETAILED DESCRIPTION

[0019] To make the purpose, technical scheme and advantages of the utility model embodiment more clear, the technical scheme in the utility model embodiment will be clearly and completely described below, obviously, the described embodiment is a part of the embodiment of the utility model, instead of all the embodiments;Based on the embodiment in the utility model, all other embodiments obtained by the ordinary skill in the art without making creative labor are within the protection scope of the utility model.

[0020] Embodiment one

[0021] As Figure 1 Shown, the utility model embodiment one provides a kind of wideband photoelectric detection device based on transimpedance circuit, including: photodiode D1, photodiode D2, transimpedance operational amplifier U1, current feedback amplifier U2;The cathode of photodiode D1 is connected with power supply anode, the anode of photodiode D1 is connected with the cathode of photodiode D2, the anode of photodiode D2 is connected with power supply cathode;The anode of photodiode D1 is also connected with the inverting input terminal of transimpedance operational amplifier U1.

[0022] Wherein, the feedback resistor R1 and the feedback capacitor C1 are connected in parallel, one end of which is connected with the output end of the transimpedance operational amplifier U1, and the other end is connected with the non-inverting input end of the transimpedance operational amplifier U1, and the inverting input end of the transimpedance operational amplifier U1 is grounded. The output end of the transimpedance operational amplifier U1 is connected with the inverting input end of the current feedback type amplifier U2 through the DC blocking capacitor C2 and the balancing resistor R3, and the resistor R5 is arranged between the inverting input end and the feedback end of the current feedback type amplifier U2, and the inverting input end is grounded through the resistor R4; and the output end of the current feedback type amplifier U2 is provided with the impedance matching resistor R6.

[0023] Further, in the embodiment, the output end of the current feedback type amplifier U2 is connected with the pin 5 of the SMA connector J1 through the impedance matching resistor R6, and the pins 1-4 of the SMA connector J1 are grounded.

[0024] Further, in the embodiment, the power supply of the transimpedance operational amplifier U1 and the current feedback type amplifier U2 is ±5V. Specifically, the positive power input end and the negative power input end of the transimpedance operational amplifier U1 are connected with +5V DC voltage and -5V DC voltage respectively; and the positive power input end and the negative power input end of the current feedback type amplifier U2 are connected with +5V DC voltage and -5V DC voltage respectively.

[0025] Specifically, in the embodiment, the PIN type photodiode is selected for the photodiode D1 and the photodiode D2, and the model is FD150, the junction capacitance is 1.5pF, the dark current is 0.5nA, and the responsivity to 1064nm laser is 0.8A / W. The model of the transimpedance operational amplifier U1 is OPA847, the bandwidth is 3.9GHz, the input voltage noise is 0.85 , and the input capacitance is 3.7pF; and the model of the current feedback type amplifier U2 is AD8000. In the embodiment, the transimpedance operational amplifier can be replaced by an operational amplifier with similar basic parameters according to the requirement, and the current feedback type amplifier U2 can be replaced by another operational amplifier with similar basic parameters according to the requirement.

[0026] Specifically, in the embodiment, the cathode of the photodiode D1 is connected with +5V DC voltage; and the anode of the photodiode D2 is connected with -5V DC voltage. In the embodiment, the two photodiodes work under +5V voltage, and the function thereof is to convert the detected optical signal into a photocurrent signal, and then the photocurrent signal enters the current feedback type amplifier U2 for two-stage amplification through the transimpedance operational amplifier U1.

[0027] Preferably, in the embodiment, the transimpedance operational amplifier U1 is of OPA847 type, the current feedback amplifier U2 is of AD8000 type, the resistance R1 is of 20kΩ, the capacitance C1 is of 0.1pF, the capacitance C2 is of 100nF, the resistance R3 is of 27Ω, the resistance R4 is of 22Ω, the resistance R5 is of 330Ω, and the resistance R6 is of 50Ω.

[0028] Embodiment two

[0029] As Figure 2 shown in the embodiment two, the wideband photoelectric detection device based on a transimpedance circuit comprises: a photodiode D1, a photodiode D2, a transimpedance operational amplifier U1, and a current feedback amplifier U2; the cathode of the photodiode D1 is connected with a positive electrode of a power supply, the anode of the photodiode D1 is connected with the cathode of the photodiode D2, and the anode of the photodiode D2 is connected with a negative electrode of the power supply; the anode of the photodiode D1 is also connected with an inverting input end of the transimpedance operational amplifier U1; a feedback resistance R1 and a feedback capacitance C1 are connected in parallel, one end of which is connected with an output end of the transimpedance operational amplifier U1, and the other end is connected with the inverting input end of the transimpedance operational amplifier U1; the non-inverting input end of the transimpedance operational amplifier U1 is grounded; the output end of the transimpedance operational amplifier U1 is connected with the non-inverting input end of the current feedback amplifier U2 through a DC blocking capacitor C2 and a balancing resistance R3; a resistance R5 is arranged between the inverting input end and the feedback end of the current feedback amplifier U2; the inverting input end is grounded through the resistance R4; and the output end of the current feedback amplifier U2 is provided with an impedance matching resistance R6.

[0030] Different from the embodiment one, the wideband photoelectric detection device based on a transimpedance circuit in the embodiment further comprises: a resistance R7 and a resistance R8; the cathode of the photodiode D1 is connected with the positive electrode of the power supply in series with the resistance R7; and the anode of the photodiode D2 is connected with the negative electrode of the power supply in series with the resistance R8. Specifically, in the embodiment, the cathode of the photodiode D1 is connected with a +5V direct current voltage in series with the resistance R7; and the anode of the photodiode D2 is connected with a -5V direct current voltage in series with the resistance R8.

[0031] Further, the wideband photoelectric detection device based on a transimpedance circuit in the embodiment further comprises a capacitance C3, a capacitance C4, a capacitance C10, and a capacitance C15; the two ends of the resistance R7 are respectively grounded through the capacitance C3 and the capacitance C4; and the two ends of the resistance R8 are respectively grounded through the capacitance C10 and the capacitance C15.

[0032] Further, the wideband photoelectric detection device based on the trans-impedance circuit in the embodiment further comprises a resistor R9 and a capacitor C5, and the non-inverting input terminal of the trans-impedance operational amplifier U1 is connected to the ground through the parallelly connected capacitor C5 and resistor R9.

[0033] Further, the wideband photoelectric detection device based on the trans-impedance circuit in the embodiment further comprises a capacitor C8 and a capacitor C11, a capacitor C9 and a capacitor C12, a capacitor C6 and a capacitor C7, and a capacitor C13 and a capacitor C14; the positive power input terminal of the trans-impedance operational amplifier U1 is connected to the ground through a first filter circuit composed of the parallelly connected capacitor C8 and capacitor C11, the negative power input terminal of the trans-impedance operational amplifier U1 is connected to the ground through a second filter circuit composed of the parallelly connected capacitor C9 and capacitor C12, the positive power input terminal of the current feedback amplifier U2 is connected to the ground through a third filter circuit composed of the parallelly connected capacitor C6 and capacitor C7, and the negative power input terminal of the current feedback amplifier U2 is connected to the ground through a third filter circuit composed of the parallelly connected capacitor C13 and capacitor C14.

[0034] Further, the wideband photoelectric detection device based on the trans-impedance circuit in the embodiment further comprises an SMA connector J1, and the output terminal of the current feedback amplifier U2 is connected to pin 5 of the SMA connector J1 through an impedance matching resistor R6, and pins 1-4 of the SMA connector J1 are connected to the ground.

[0035] Preferably, in the embodiment, the model of the trans-impedance operational amplifier U1 is OPA847, the model of the current feedback amplifier U2 is AD8000, the resistance of the resistor R1 is 20kΩ, the capacitance of the capacitor C1 is 0.1pF, the capacitance of the capacitor C2 is 100nF, the resistance of the resistor R3 is 27Ω, the resistance of the resistor R4 is 22Ω, the resistance of the resistor R5 is 330Ω, and the resistance of the resistor R6 is 50Ω. Through experimental tests, the working bandwidth of the wideband photoelectric detection device can reach 400MHz, and the signal-to-noise ratio can reach 20dB.

[0036] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A wideband photodetector device based on a transimpedance circuit, characterized by It includes: Photodiode D1, photodiode D2, transimpedance operational amplifier U1, current feedback amplifier U2; the cathode of photodiode D1 is connected with the positive pole of power supply, the anode of photodiode D1 is connected with the cathode of photodiode D2, the anode of photodiode D2 is connected with the negative pole of power supply; the anode of photodiode D1 is also connected with the inverting input terminal of transimpedance operational amplifier U1; The feedback resistor R1 is connected with the feedback capacitor C1 at one end, and the other end is connected with the output terminal of transimpedance operational amplifier U1, and the other end is connected with the inverting input terminal of transimpedance operational amplifier U1, and the noninverting input terminal of transimpedance operational amplifier U1 is grounded; The output terminal of transimpedance operational amplifier U1 is connected with the noninverting input terminal of current feedback amplifier U2 through the DC blocking capacitor C2 and the balancing resistor R3, and the resistor R5 is arranged between the inverting input terminal and the feedback terminal of current feedback amplifier U2, and the inverting input terminal is grounded through the resistor R4; the output terminal of current feedback amplifier U2 is connected through the impedance matching resistor R6.

2. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, It also includes: Resistor R7 and resistor R8; the cathode of photodiode D1 is connected with the positive pole of power supply after being connected with resistor R7 in series, and the anode of photodiode D2 is connected with the negative pole of power supply after being connected with resistor R8 in series.

3. The wideband photodetector device based on a transimpedance circuit according to claim 2, characterized in that, It also includes: It also includes capacitor C3, capacitor C4, capacitor C10 and capacitor C15, the two ends of resistor R7 are respectively connected with the ground through capacitor C3 and capacitor C4, and the two ends of resistor R8 are respectively connected with the ground through capacitor C10 and capacitor C15.

4. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, It also includes resistor R9 and capacitor C5, and the noninverting input terminal of transimpedance operational amplifier U1 is grounded through the parallelly connected capacitor C5 and resistor R9.

5. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, The positive power input terminal of transimpedance operational amplifier U1 is grounded through the first filter circuit composed of parallelly connected capacitor C8 and capacitor C11, the negative power input terminal of transimpedance operational amplifier U1 is grounded through the second filter circuit composed of parallelly connected capacitor C9 and capacitor C12, the positive power input terminal of current feedback amplifier U2 is grounded through the third filter circuit composed of parallelly connected capacitor C6 and capacitor C7, and the negative power input terminal of current feedback amplifier U2 is grounded through the fourth filter circuit composed of parallelly connected capacitor C13 and capacitor C14.

6. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, The positive power input terminal and the negative power input terminal of transimpedance operational amplifier U1 are respectively connected with +5V direct current voltage and-5V direct current voltage; the positive power input terminal and the negative power input terminal of current feedback amplifier U2 are respectively connected with +5V direct current voltage and-5V direct current voltage.

7. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, The cathode of photodiode D1 is connected with +5V direct current voltage; the anode of photodiode D2 is connected with-5V direct current voltage.

8. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, The model of photodiode D1 and photodiode D2 is FD150, the model of transimpedance operational amplifier U1 is OPA847, and the model of current feedback amplifier U2 is AD8000.

9. The wideband photodetector device based on a transimpedance circuit according to claim 1, wherein, It also includes SMA connector J1, the output terminal of current feedback amplifier U2 is connected with pin 5 of SMA connector J1 through impedance matching resistor R6, and pins 1-4 of SMA connector J1 are grounded.

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