For this application, the design
requirements are as follows:
- VS+ = 5 V, VS– = –5 V, VCM =
GND, REFA = GND
- IREF (1 µA) connected to
I2
- Input current range: 10 nA ≤
I1 ≤ 100 µA
- Photodiode: GP8195-12
- VR = 5
V
- 20 pA dark current
(typical)
- 1-pF typical
capacitance (1.5‑pF maximum)
- Spectral response
range from λ = 0.9 μm to λ = 1.7 μm
For bench testing of the system, the
following configuration is used:
- Laser diode: LPS-1310-FC
- λ = 1.31 μm
- Threshold current 5
mA to 20 mA
- Current control mode
used
- Laser controller: THOR
CLD1010
- Variable attenuator:
VOA50-FC-SM 50-dB in-line
- External modulation: Agilent
33250A 80‑MHz waveform generator