Very prone to HF oscillations (by Gerard Larooy)

Component: LM380

Category: Analog IC's

Old enough to go bald let alone vote. This audio amplifier chip was intended for people to use in products saving development time. It's not a HiFi device but it saves space. Hence it was popular in receivers.

It's very prone to HF oscillations making designers wonder why their receiver design was full of noise and spurs. Placing the LM380 close to a ferrite rod proves this. The R&D effort to get basic audio is much less than a synthesized comms receiver. The LM380 in this instance created an order of magnitude more problems than it solved. Two 380N-8's were bridged to form an amplitude modulator for a NZ made CB radio. People wondered for years why these sets caused more interchannel splatter.

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