J
John Larkin
- Jan 1, 1970
- 0
But this reliability issue has nothing to do with the topology.
Another reason I like this opamp-Vcc current splitter thing (it really
deserves a decent name) is that you can know for sure what the maximum
drive is going to be into the power current mirrors. So even if the
loop goes wide open, you can fully define, by design, the output stage
peak power dissipation, and arrange for soa shutdown before the
silicon melts. That helps make the design reliable and fault-tolerant.
I've seen (er, designed) discrete amps that had great foldback current
limiting in the output stages, and consequently, when overloaded, blew
up the drivers.
Discretes don't have poles? I just use an opamp here that has 100x the
loop bandwidth, and don't worry about that part.
John