GENERAL DESCRIPTION
No external Schottky diode is required across the internal synchronous rectifier switch. The MAX1536 produces dynamically adjustable output voltages for chipsets and graphics processor cores using a logic-level control signal. The MAX1536 achieves efficiencies as high as 96%. The MAX1536 uses a unique current-mode, constant-offtime, PWM control scheme. It has selectable Idle ModeTM to maintain high efficiency during light-load operation, or fixed-PWM mode for low output ripple. The programmable constant-off-time architecture allows a wide range of switching frequencies up to 1.4MHz, optimizing performance trade-offs between efficiency, output switching noise, component size, and cost. The MAX1536 features a digital soft-start to limit surge currents during startup, a 100% duty-cycle mode for lowdropout operation, and a low-power shutdown mode that disconnects the input from the output and reduces supply current below 1µA. The MAX1536 is available in a 28-pin thin QFN package with an exposed backside pad.
Maxim Integrated
