TIASim - Transimpedance Amplifier Simulation.
For some example designs and comparisons to TIASim see One Inch Phototdetector or Two-stage photodetector.
Analog Devices has a Photodiode Circuit Design Wizard at https://tools.analog.com/en/photodiode/
- Hobbs, Photodiode front ends
- Transimpedance Amplifiers (TIA): Choosing the Best Amplifier for the Job, http://www.ti.com.cn/cn/lit/an/snoa942a/snoa942a.pdf
- Transimpedance Considerations for High-Speed Amplifiers http://www.ti.com/lit/an/sboa122/sboa122.pdf
- RF lower than 2 kOhm -> use BJT opamp
- RF higher than 2 kOhm -> use FET opamp
- Scott et al. 2001, "High-dynamic-range laser amplitude and phase noise measurement techniques" DOI:10.1109/2944.974236
Open-loop gain, input-referred voltage and current noise, and input-capacitance are modeled for the following op-amps:
| Op-amp | Input | Bandwidth | Inp Capacitance | Supply Voltage |
|---|---|---|---|---|
| OPA814 | FET | 0.6 GHz | 2.7 pF (2.5pF cm, 0.2 pF diff) | 12.6 V |
| OPA817 | FET | 0.4 GHz | 3.0 pF (2.9pF cm, 0.1 pF diff) | 12.6 V |
| OPA657 | FET | 1.6 GHz | 5.2 pF | 13 V |
| OPA859 | FET | 1.8 GHz | 0.8 pF | 5 V |
| OPA818 | FET | 2.7 GHz | 2.4 pF (1.9pF cm, 0.5pF diff) | 13 V |
| OPA847 | BJT | 3.9 GHz | 3.7 pF | 13 V |
| OPA858 | FET | 5.5 GHz | 0.8 pF | 5 V |
| OPA855 | BJT | 8 GHz | 0.8 pF | 5 V |
| LTC6268-10 | FET | 4 GHz | 0.55 pF | 5 V |
These integrated TIAs might be good for comparisons: HMC799 (10kOhm, 700 MHz, TIA), LTC6560 (74 kOhm, 220 MHz)
| Photodiode | Material | Capacitance | Active area | Notes |
|---|---|---|---|---|
| Hamamatsu S5973 | Si | 1.6 pF | D=0.4 mm | |
| Hamamatsu S5971 | Si | 4.0 pF | D=1.2 mm | |
| Thorlabs FDS015 | Si | 0.65 pF | D=0.15 mm | FCI-125G-006HR |
| Thorlabs FDS025 | Si | 0.94 pF | D=0.25 mm | Ball lens, FCI-125G-010HRL |
| Thorlabs FGA01FC | InGaAs | 2.0 pF | D=0.12 mm | FC-connector, INGAAS-120L-FC |
| Thorlabs FGA015 | InGaAs | 1.5 pF | D=0.15 mm | |
| Fermionics FD80FC | InGaAs | 0.4 pF | D=0.08 mm | FC-connector |
https://www.ti.com/lit/ds/symlink/opa818.pdf
This image compares TIASim predicted bandwidth vs. photodiode capacitance and transimpedance to the datasheet front-page Figure. Note that the TIASim CF values are increased by a sqrt(2) factor. CF is the capacitance across RF.
This image shows measured and predicted dark and bright noise levels for an OPA818 photodetector with 1.2 kOhm transimpedance and 0.7 pF CF. The Photodiode is a Thorlabs FDS015. The -3dB badwidth is >400 MHz.
http://www.ti.com/lit/ds/symlink/opa657.pdf
This OPA657 photodetector with S5791 photodiode and 1 MOhm transimpedance shows 4 MHz bandwidth. Note that this design has no output-buffer, and the TIASim predicted response was adjusted to fit the measurement data by de-rating the op-amp GBWP.
This OPA657 detector with S5793 photodiode and 10 kOhm transimpedance (0.2 pF CF) shows ca 60 MHz bandwidth.
