Charge pump at 35 kHz, 25 mA output
The MAX829EUK+T: The 35 kHz switching frequency keeps external capacitor values small — typically 10 µF for the flying and reservoir caps — which suits compact single-rail designs needing a negative bias or a doubled supply without an inductor. The output configuration is selectable as positive or negative, meaning one part covers both inverting and doubling applications. No synchronous rectifier is used, so efficiency is moderate — expect around 80-85% at full load — but the simplicity of a two-capacitor charge pump is the trade-off for low BOM count.
Housed in a 5-lead SOT-23 (SC-74A, SOT-753) surface-mount package, the MAX829EUK+T occupies minimal board area. The SOT-23-5 footprint is standard; the datasheet shows the recommended land pattern on page 7 for the solder pad geometry.
For BOM planning, this part is sourced through authorized and independent distribution channels.