I am having difficulty finding a power op amp with the following characteristics. Can anyone offer suggestions?
_Single supply_ 12VDC operation, IOW no biasing network required. Frequency range DC to 1KHz Max current out 1A
It is being used as a positioning coil driver. Other parameters are non-critical.
Thank you for any help with a part number.
Kenneth Warren
Any op amp rated for operation at (V+ - V-)
Depending on the nature of your input signal, you may not require biasing to mid-supply. I cannot name an amplifier off the top of my head but Apex, Texas Instruments, and National have op-amps with high output current that are > 1A. BTW, 1A continuous output current?
Usually an opamp plus a power-darlington BJT or a Mosfet is used for this application. Since the current is only of one polarity, a very simple stage is needed. Maybe better would be a voltage controlled current source, easily implemented with a few components. The driving force of the coil is proportional to the current But you should have measured much more data of your linear motor, or given a link to a datasheet to get some better advice.
I think you might find something usable if you browse through the audio amplifier (speaker driver) chips, instead of opamps. There are even some class D (switching) drivers that might do the job with higher efficiency.
You might be able to use the old venerable LM12 which can operate single rail.
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