The MAX1692 is a low-noise, pulse-width-modulated (PWM), DC-DC step-down converter. It is suitable for powering logic and transmitters in small wireless systems. The device features an internal synchronous rectifier for high efficiency and does not require an external Schottky diode. It has excellent noise characteristics and fixed-frequency operation for easy post-filtering. The MAX1692 is ideally suited for Li-Ion battery applications and can also be used for +3V or +5V fixed input applications. It operates in four modes: Forced PWM mode, Synchronizable PWM mode, Idle Mode™ (PWM/PFM), and Shutdown mode. The MAX1692 can deliver over 600mA of output current, with an adjustable output voltage range from 1.25V to VIN and an input range from +2.7V to +5.5V. Other features include high efficiency, low dropout voltage, and a 1.2%-accurate 1.25V reference.
The MAX1692 is a low‑noise, pulse‑width‑modulated DC‑DC step‑down converter designed for small wireless systems such as cellular phones, PDAs and handy‑terminals. It features an internal synchronous rectifier, fixed‑frequency operation at 750 kHz, and four operating modes (Forced PWM, Synchronizable PWM, PWM/PFM and Shutdown) to optimize efficiency and quiescent current.
Typical applications include battery‑operated devices, Li‑Ion powered equipment, and any circuit requiring a compact 10‑pin µMAX package with an adjustable output from 1.25 V up to the input voltage. The datasheet provides absolute maximum ratings, electrical characteristics, and design guidelines for capacitor selection and layout.
| Input Voltage Range | +2.7 V to +5.5 V |
|---|---|
| Adjustable Output Voltage | 1.25 V to V_IN |
| Maximum Output Current | 600 mA |
| Efficiency | up to 95 % |
| Quiescent Current (Normal) | 85 µA |
| Shutdown Supply Current | < 0.1 µA |
| Switching Frequency | 750 kHz (fixed) or 500‑1000 kHz sync |
| Package | 10‑pin µMAX (height 1.11 mm) |
| Operating Temperature Range | -40 °C to +85 °C |
The device operates from +2.7 V up to +5.5 V.
It can deliver up to 600 mA of output current.
In shutdown mode the supply current is reduced to less than 0.1 µA.
The internal oscillator runs at a fixed 750 kHz, but can be synchronized between 500 kHz and 1 MHz.