I've been looking at DACs on Digikey and other electronics sites in hopes of finding a circuit to drive > 20 electrical nodes with ~10 mA per channel, 0->8V, with ~16-bit precision. I've seen evaluation boards from Analog Devices that offer 40 channels with the specifications, but they can only handle 1 mA load current. Does anyone have any suggestions for pre-made systems that could handle this sort of situation?
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closed as off-topic by Michael Karas, tcrosley, Matt Young, alexan_e, Daniel Grillo Feb 3 '14 at 18:50
This question appears to be off-topic. The users who voted to close gave this specific reason:
DACs typically don't sink or source much current; typically to drive the output harder you use an op-amp which can drive to your requirements on the output of the DAC. If you need even more current than that, you can use a pass transistor or FET on the op-amp output and close the loop around it.
This psocdeveloper forum post goes into more detail about using a FET in the output path of a voltage-following op-amp which is connected to the output of a DAC in order to boost the current capability of the DAC. As I mentioned though, practically any op-amp can give you 10mA sink/source capability so you probably do not need to go this far.
A quick Digikey search shows op-amps like the MAX4495, AD8625 and HT1104 can supply 15mA per channel. You might want to take a look there and see where it leads you.