Step-down regulator has dynamic output control

A Maxim Integrated Products product story

Edited by the Electronicstalk editorial team Jan 28, 2003

The MAX1536 is a 3.6A internal switch, step-down DC/DC convertor ideal for 5 and 3.3V to low-voltage conversion in notebooks, subnotebooks and desk notes.

The MAX1536 is a 3.6A internal switch, step-down DC/DC convertor ideal for 5 and 3.3V to low-voltage conversion in notebooks, subnotebooks and desk notes.

The MAX1536 features an internal PMOS power switch and synchronous rectification for high efficiency and reduced component count.

The internal 54mohm PMOS power switch and 47mohm NMOS synchronous-rectifier switch easily deliver continuous load currents up to 3.6A.

This device produces an adjustable output from 0.7V to the input voltage and achieves efficiencies as high as 96%.

The MAX1536 uses a unique current-mode constant-off-time PWM control scheme.

It has a selectable idle mode to maintain high efficiency during light-load operation, or fixed PWM-mode for low output ripple.

The programmable constant-off-time architecture allows for a wide range of switching frequencies up to 1.4MHz.

This optimises performance tradeoffs between efficiency, output switching noise, component size, and cost.

The MAX1536 features a digital soft-start to limit surge current during startup, a 100% duty-cycle mode for low-dropout operation, and a low-power shutdown mode to disconnect the input from the output and reduce supply current below 1uA.

The MAX1536 is available in a 28-pin thin QFN package.

Prices start at $4.69 (1000-up, FOB USA).

A pre-assembled evaluation kit with recommended external components is available to speed design.

(This was Electronicstalk's Top Story on 26 January 2003).