[sdiy] Chopper amps

[Nicholas Gregorich]

I attended a TI seminar on power electronics today but they were giving away a couple ADCs, a DAC, and a precision opamp.

Its the OPA333, a chopper amp.

http://focus.ti.com/docs/prod/folders/print/opa333.html#samples?DCMP=TI_Portal_Brand_Tracking&HQS=Other+OT+portal_bc_opa333

I didn't learn about choppers in school but it seems as though they compensate for offset voltages due to part mismatches, temperature drift, and time drift using some sort of clocked "sampling".

Are chopper amps used in synthesizers or other music or even audio gear?  The OPA333 is supposedly a new design that includes a notch filter to eliminate the chopper noise associated with older designs.

Unfortunately the part is specified for single supply 5V, so I don't think it is useful for SDIY application.

Anyhow, just excited to share about something I learned today (amongst a lot of DC to DC conversion) and see if its something found in the SDIY community (or even commercial products).

Nick