The MAX727/MAX728/MAX729 5V/3.3V/3V 2A Step-Down, PWM, Switch-Mode DC-DC Regulators is a high-performance switch power supply from Maxim Integrated Products
The MAX727, MAX728 and MAX729 are monolithic, bipolar PWM step‑down DC‑DC regulators rated at 2 A. They require few external components because the power switch, oscillator, feedback and control circuitry are integrated on‑chip. Each device is supplied in a 5‑pin TO‑220 package and operates over a wide input range.
Key features include a preset 100 kHz switching frequency, on‑chip current limiting, low quiescent current (8.5 mA), and a variety of temperature‑rated versions. The datasheet provides absolute maximum ratings, electrical characteristics, pin functions and mechanical dimensions.
| Input Voltage Range | Up to 40 V |
|---|---|
| Fixed Output Voltage | 5 V (MAX727), 3.3 V (MAX728), 3 V (MAX729) |
| Switching Frequency | 100 kHz |
| Quiescent Current | 8.5 mA |
| Package | 5‑pin TO‑220 |
| Maximum Duty Cycle | 85 % – 100 % |
| Operating Temperature Range (MAX727CCK) | 0 °C to +70 °C |
The devices accept an input voltage up to 40 V.
MAX727 provides 5 V, MAX728 provides 3.3 V, and MAX729 provides 3 V.
They operate at a preset 100 kHz switching frequency.
All three regulators are supplied in a 5‑pin TO‑220 package.