The MAX1776 high-efficiency step-down converter provides an adjustable output voltage from 1.25V to VIN from supply voltages as high as 24V. An internal current-limited 0.4Ω MOSFET delivers load currents up to 600mA. Operation to 100% duty cycle minimizes dropout voltage (240mV at 600mA). The MAX1776 has a low 15µA quiescent current to improve light-load efficiency and conserve battery life. The device draws only 3µA while in shutdown. High switching frequencies (up to 200kHz) allow the use of tiny surface-mount inductors and output capacitors. The MAX1776 is available in an 8-pin µMAX package, which uses half the space of an 8-pin SO. For increased output drive capability, use the MAX1626/MAX1627 step-down controllers, which drive an external P-channel MOSFET to deliver up to 20W.
The MAX1776 is a high‑efficiency step‑down (buck) converter that accepts input voltages from 4.5 V to 24 V and provides an adjustable output from 1.25 V up to the input voltage. It features an internal 0.4 Ω P‑channel MOSFET, delivers up to 600 mA output current, and operates with up to 200 kHz switching frequency to allow small inductors and capacitors.
Typical applications include notebook computers, handheld devices, and keep‑alive power supplies. The device offers very low quiescent current (15 µA) and an ultra‑low shutdown current (3 µA), making it suitable for battery‑powered designs. Protection features include current‑limit architecture, thermal shutdown, and a 100 % maximum duty cycle for low dropout voltage.
| Input Voltage Range | 4.5 V to 24 V |
|---|---|
| Maximum Output Current | 600 mA |
| Efficiency | over 95 % |
| Dropout Voltage at 600 mA | 240 mV |
| Maximum Switching Frequency | 200 kHz |
The MAX1776 can deliver up to 600 mA of output current.
The converter operates from 4.5 V up to 24 V input.
Typical efficiency is greater than 95 %.