3G InGaAs Pulse APD Diode Pins for OTDR (APD: Avalanche Photo Diode)
The APD/avalanche photo diode (3G InGaAs pulse APD diode pins for OTDR) is a p-n junction photodetector made of silicon or germanium. By applying a reverse bias voltage to the p-n junction, the incident light photons will strike the electrons in order to push them through a junction, thus achieving photoelectric current flows. When the applied reverse voltage increases, an avalanche current flow will occur. The avalanche effect of the current carrier is then used to amplify the photoelectric signal in the detection system in order to improve detector sensitivity.
This photo diode series features a small dark current, low operating voltage, and high sensitivity. It can operate in the pulse output mode or DC output mode, and is often used in OTDR systems and detection equipment for Raman backscattering systems.
Absolute Maximum Ratings| Parameter | Symbol | Min. | Typ. | Max. | Unit |
| Forward Current | IF | | | 10 | mA |
| Reverse Current | IR | | | 0.5 | mA |
| Operating Temp. | TC | -40 | | 85 | °C |
| Storage Temperature | TSTG | -40 | | 85 | °C |
| Lead Soldering Temp. | TSOL | - | | 260(10s) | °c |
| Relative Humidity | RH | 0 | | 85 | % |
| Parameter | Symbol | Min. | Typ. | Max. | Unit | Notes |
| Reverse Breakdown Voltage | VBR | 40 | 45 | 55 | V | ID = 100 μA |
| Temperature Coefficient of Reverse Breakdown Voltage1 | δ | | 0.2 | | %/°C | |
| Dark Current | ID | | 5 | 25 | nA | VR = VBR*0.9 |
| Multiplied Dark Current | IDM | | 1 | 3 | nA | M = 2 to 10 |
| Terminal Capacitance | Ct | | 0.35 | | pF | VR = VBR* 0.9, f = 1 MHz |
| Cut-off Frequency | fC | 2.5 | | | GHz | M = 10 |
| Quantum Efficiency | η | 76 | 90 | | % | λ = 1310 nm, M = 1 |
| 65 | 77 | | λ = 1550 nm, M = 1 | |||
| Responsivity | S | 0.85 | 0.90 | | A/W | λ = 1310 nm, M = 1 |
| 0.90 | 0.95 | | λ = 1550 nm, M = 1 | |||
| Excess Noise Factor | X | | 0.7 | | - | λ = 1310 nm, IPO = 1.0 μw, M = 10, f = 35 MHz, B = 1 MHz |
| F | | 5 | | λ = 1550 nm, IPO = 1.0 μw, M = 10, f = 35 MHz, B = 1 MHz | ||
| Optical Return Loss | ORL | 30 | 40 | | dB | SMF |
