Maxim's High-efficiency, Triple-output, Keep-alive Power Supply For Notebook Computers

Maxim Integrated Products introduces the MAX1534 high-efficiency, triple-output power supply for keep-alive (always on) voltage rails. The MAX1534's 450mA buck-regulator with an internal current-limited 0.5 PMOS steps down the battery or wall adapter supply rail to a fixed 5V or an adjustable output voltage. Two integrated low-voltage linear regulators follow this output and provide two independent preset output voltages of 3.3V and 1.8V, or adjustable output voltages. A power-OK (POK) signal that indicates when all outputs are in regulation is also included.

The MAX1534's buck-regulator utilizes a peak current-limit, pulse-frequency modulation (PFM) architecture for highest light-load efficiency to conserve battery life, and high switching frequencies allow the use of tiny surface-mount inductors and output capacitors. The low-dropout linear regulators use an internal P-channel (PMOS) pass transistor to deliver up to 160mA continuous current and to minimize supply current.

The MAX1534 is available in a small 16-pin thin QFN (4mm x 4mm), occupying 33% less board space than discrete solutions. Prices for the MAX1534 start at $2.90 (1000-up, FOB USA). An evaluation kit is available with recommended external components to reduce design time.

Additional Information:

Full Data Sheet (PDF)