Step-up regulator with dual-topology flexibility
The MAX631ACPA+ is a step-up switching regulator from Analog Devices that operates in either boost or charge-pump topology, configurable for positive or negative output voltages. It delivers up to 450 mA via its integrated switch at a 45 kHz switching frequency. Input voltage spans 2 V to 16.5 V, and the output is adjustable from a 1.31 V reference or fixed at 5 V, covering common 5 V rail generation from lower-voltage sources like two-cell batteries or 3.3 V buses.
Package and thermal fit for through-hole designs
Housed in an 8-pin DIP (0.300" width, 7.62 mm row spacing), the MAX631ACPA+ uses through-hole mounting — the 8-PDIP body dissipates heat through the leads into the PCB copper; no exposed pad or heatsink is needed at the 450 mA switch current level. The commercial temperature grade (0 °C to 70 °C) suits benchtop instrumentation, telecom line cards, and indoor power supplies where ambient stays within that band. No synchronous rectifier is used, so efficiency at light loads is lower than a modern synchronous part — budget the diode forward drop into the thermal calculation.