How to build up or where to buy an ac current source?

[a8811323]

Hi,
I have a conductivity sensor that is supplied ac current. For my project I want to supply a constant ac current (200-3000 Hz) normally in 0.1mA to 0.35mA range, typically 0.3mA. Is there any commercial product can output such current source? The most of product is actually working only for dc such as current regulator. Can anyone tell me how to search for this kind of chip?
Regards
Chenjin

 

[KlausST]

Hi,

For my project I want to supply a constant ac current (200-3000 Hz) normally in 0.1mA to 0.35mA range, typically 0.3mA.

Usually almost any OPAMP with the approriate circuit can do the job.
Look for "Howland constant current source" for example.

Klaus

 

[FvM]

Maximum output voltage and required impedance are important parameters.

 

[a8811323]

Maximum output voltage and required impedance are important parameters.

Hi
The output current I give already increased the consideration of the maximum output voltage and impedance parameters. My question is since the current I needed is so small, are there many commercial products can meet this requirement?

 

[FvM]

The output current I give already increased the consideration of the maximum output voltage and impedance parameters.

Doesn't answer the question, unfortunately.

are there many commercial products can meet this requirement?

Commercial product means IC, signal processing module, test instrument?

In case you are referring to ready made AC current source ICs, I'm not aware of any. In some way, OTAs can be considered as AC capable current source, but I guess, it's not what you want.

The question how to build up a current source was already answered by KlausST.