Charge pump with ratiometric output
The MAX865EUA+ from Analog Devices is a charge pump DC-DC converter that generates a regulated output voltage from an input as low as 1.5 V and up to 6 V. Its ratiometric function means the output tracks the input as a fixed multiple — the fixed outputs are -Vin and 2Vin, giving you either a negative rail or a doubled positive rail from a single supply. With two outputs configurable as positive or negative, this part suits applications where a bipolar supply is needed from a single battery cell or low-voltage rail — think op-amp front-ends, LCD bias, or sensor signal chains that need a clean -5 V from a 5 V bus.
20 mA output and switching frequency
Each output delivers up to 20 mA continuous. At this current level the charge pump's internal switching losses are low enough that the 18 kHz to 34 kHz oscillator range keeps ripple manageable without external filtering — the lower end of the band is below audible frequencies, which matters for audio-path supplies. The absence of synchronous rectification means the output diodes carry the forward drop — budget around 0.4 V to 0.5 V per diode at 20 mA, which sets the practical headroom needed between input and the desired output rail.
Temperature grade and board integration
Housed in the 8-uMAX/uSOP package (3.00 mm width, 0.118" pitch), this surface-mount part fits tight board layouts. The 8-MSOP footprint is common, so the PCB land pattern is standard; no special thermal pad or exposed paddle to design around.
Active production and compliance
Supplied in tube packaging — typical for small MSOP quantities in prototyping or low-volume production. For reel packaging check the -T suffix variant if pick-and-place volume requires it.