graeme_cunningham
Newbie level 3
I am quantifying the characteristics and performance of a device that includes a photodiode.
Currently my set up involves the photocurrent generated by a photodiode going into a pre-amplifier and then additional signal processing elements.
My new experiment involves the use of low current ammeter. The meter is different from a normal ammeter in that it sinks the current rather than being a low impendence element in series in the circuit. I need to be able to switch between the photocurrent flowing into pre amplifier and flowing into the ammeter.
Obviously I could add a switch to the PCB, however(for reasons I won’t go into) I can’t access the board during the test. There is however cable coming off the PCB.
I am thinking of using a miniature PCB single pole double throw relay, which I could activate remotely. Does this sound like a good idea or can anyone suggest a better solution. Can anyone recommend a suitable component as I do not have any experience in their use.
My main design restriction is that I want to minimise noise as much as I can. I will be measuring current in the 1-100nA range. Many Thanks in advance.
Graeme
Currently my set up involves the photocurrent generated by a photodiode going into a pre-amplifier and then additional signal processing elements.
My new experiment involves the use of low current ammeter. The meter is different from a normal ammeter in that it sinks the current rather than being a low impendence element in series in the circuit. I need to be able to switch between the photocurrent flowing into pre amplifier and flowing into the ammeter.
Obviously I could add a switch to the PCB, however(for reasons I won’t go into) I can’t access the board during the test. There is however cable coming off the PCB.
I am thinking of using a miniature PCB single pole double throw relay, which I could activate remotely. Does this sound like a good idea or can anyone suggest a better solution. Can anyone recommend a suitable component as I do not have any experience in their use.
My main design restriction is that I want to minimise noise as much as I can. I will be measuring current in the 1-100nA range. Many Thanks in advance.
Graeme
