What the 1.5A switch rating means for your BOM
The MC34063ECN integrates a 1.5A switch — that's the peak current the internal transistor can handle, not the continuous output. For a buck converter at 12V in, 5V out, you'll get about 500-700 mA output before the switch current limit kicks in. The 33kHz switching frequency forces you into larger magnetics — a 100-220 µH inductor and 100-470 µF output cap are typical, so the BOM footprint is noticeably bigger than a modern 500 kHz part.
Input voltage range and topology flexibility
It accepts 3V to 40V input and can regulate an adjustable output from 1.25V up to 38V. The output can be positive or negative, and the part supports both buck and boost topologies. That makes it a single-component solution for a bench supply or a multi-rail board where you need both step-up and step-down from the same IC — just rewire the external network.
Package and temperature — where it fits
The 8-DIP package is through-hole, so it's breadboard-friendly and easy to hand-solder in prototyping or low-volume production.
It's a mature, widely second-sourced part — the MC34063A from multiple vendors is pin-compatible. No stock-holding claim here — it's sourced per RFQ.