I need a differential output AC constant current source of around 100 or 200mA. Freq is around 20 Hz.
Can I build that using a pair of Howland Current pump ?
Or is there any reference design using any ADI parts ?
AD8016 and AD8017 are amplifiers with high output current.
Here are the links for their datasheets:
AD8016 - http://www.analog.com/static/imported-files/data_sheets/AD8016.pdf
AD8017 - http://www.analog.com/static/imported-files/data_sheets/AD8017.pdf
Also, an additional resource for current source circuits is AN-968. You can read it here - http://www.analog.com/static/imported-files/application_notes/AN-968.pdf
Hope this helps!
You may refer to Figure 3 of CN0143 and Figure 3 of CN0151. I think it would help you by just tweaking the values of the resistors and capacitors to get your desired output load of 100mA to 200mA.
CN0151 uses a Howland current pump but is in a single-ended output configuration. Just use two of it and modify it.
Here are the links:
CN0143 - http://www.analog.com/static/imported-files/circuit_notes/CN0143.pdf
CN0151 - http://www.analog.com/static/imported-files/circuit_notes/CN0151.pdf
Hope this helps.
AD8510 is low current op-amp.
Any suggestion on amplifiers for 200mA current source ?
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