I need some help on getting started on a photodiode amp. design for a school project.
I will need to design a Transimpedance amplifier for a Hamamatsu S1226 Photodiode.
How do I design a TIA with 1Mhz BW. How to bascially start the design on calculating the Rf, Cf, gain, F3db, etc, etc. ?
I suppose, you are not going to design an amplifier, but to use an existing opamp IC as a transimpedance amplifier, right ?
At first you have to select an IC which is able to handle 1 MHz. Thus, its transit frequency should be at least 20...50 MHz.
For designing the passive parts around this amplifier you can make use of the attached paper. Good luck !
Thanks for the response, it is very helpful. Yes, I need to pick an op-amp IC. But how do I know how much current the PD is able to output, I am using a wide range of wavelengths 150 to 800 nm.. I need to pick a low noise, wide dynamic range op-amp. Any suggestions ?
Thanks for the response, it is very helpful. Yes, I need to pick an op-amp IC. But how do I know how much current the PD is able to output, I am using a wide range of wavelengths 150 to 800 nm.. I need to pick a low noise, wide dynamic range op-amp. Any suggestions ?
The wavelength of the light is not that important when choosing an amplifier (the only real effect it will have is the photodiode will probably give more current towards the red end of the visible spectrum for the same light power as it would for blue light).
The current supplied by the photodiode is not going to be large, so you shouldn't worry to much about that either.
The data sheet for the PD should give you an A/W reading which will allow you to calculate the current for whatever wattage of light is incident to the detector.
Some circuits have been previously mentioned so I'd go with one of them.
I'm guessing you're going to be shining modulated light onto this sensor, since you're concerned about the bandwidth of the amplifier. Modulated light detection is quite an interesting field of research.