Conclusion

The MAX1921 sucessfully meets the quality and reliability standards required of all Maxim products. In

addition, Maxim’s continuous reliability monitoring program ensures that all outgoing product will continue to meet

Maxim’s quality and reliability standards.

Table of Contents

I. ........Device Description

V. ........Quality Assurance Information

II. ........Manufa cturing Information

VI. .......Reliability Evaluation

III. .......Packaging Information

IV. .......Die Information

......Attachments

I. Device Description

A. General

The MAX1921 step-down converter delivers over 400mA to outputs as low as 1.25V. This converter uses a unique

proprietary current-limited control scheme that achieves over 90% efficiency. This device maintains extremely low

quiescent supply current (50µA), and it’s high 1.2MHz (max) operating frequency permits small, low-cost external

components. This combination makes the MAX1921 an excellent high-efficiency alternative to linear regulators in

space-constrained applications.

Internal synchronous rectification greatly improves efficiency and eliminates the external Schottky diode required in

conventional step-down converters. The device also includes internal digital soft-start to limit input current upon

startup and reduce input capacitor requirements.

The MAX1921 provides factory-preset output voltages (see the Selector Guide) and is available in space-saving 6-pin

SOT23 packages

B. Absolute Maximum Ratings

Item

Rating

IN, FB, SHDN to AGND

-0.3V to +6V

OUT to AGND, LX to PGND

-0.3V to (IN + 0.3V)

AGND to PGND

-0.3V to +0.3V

OUT Short Circuit to GND

10s

Operating Temperature Range

-40°C to +85°C

Junction Temperature

+150°C

Storage Temperature

-65°C to +150°C

Lead Temperature (soldering 10s)

+300°C

Continuous Power Dissipation (TA = +70

°C)

6-Pin SOT23

696mW

Derates above +70

°C

6-Pin SOT23

8.7mW/

°C