Active production — 1.5 A switch, 33 kHz, buck/boost in SOIC-8
The MC34063ACD-TR is an active-production STMicroelectronics switching regulator that handles step-up (boost) and step-down (buck) conversion from a single IC. Its 1.5 A integrated switch and 33 kHz switching frequency suit moderate-power rails in cost-sensitive designs.
Parametric range and topology flexibility
The 1.5 A switch current rating is the peak limit through the internal transistor — the actual output current depends on the input-to-output voltage differential and the inductor chosen. At 33 kHz, the switching period is roughly 30 µs, so the inductor ripple current and core size are larger than a modern 500 kHz part, but the low frequency keeps switching losses minimal. The output can be configured as positive or negative, and the topology supports both buck and boost without external level-shifting — a single inductor and a few passives complete the converter. No synchronous rectifier is integrated, so an external Schottky diode handles the freewheeling path.
Temperature grade and package fit
The tape-and-reel variant (TR suffix) is the production reel quantity; cut-tape (CT) is also listed for prototype or low-volume builds.