HIGH-SPEED STEP-DOWN CONTROLLER WITH ACCURATE CURRENT LIMIT FOR NOTEBOOK COMPUTERS
SUNNYVALE, CA-June 13, 2001-Maxim Integrated Products introduces the MAX1844 single PWM controller with high efficiency, excellent transient response, and high DC output accuracy needed for stepping down high-voltage batteries to generate low-voltage supplies in notebooks.
The quasi fixed-frequency on-demand PWM controller is Maxims QUICK-PWM, a free-running constant on-time type with input feed-forward. This provides ultra-fast transient response, wide input-output differential range, low supply current, and tight load regulation characteristics. The MAX1844 is simple, easy to compensate, and does not have the noise sensitivity and duty factor limitations of conventional fixed-frequency current-mode PWMs. The MAX1844 is intended for CPU core, chipset, I/O, and DRAM or other low-voltage supplies as low as 1V.
To ensure reliable overload protection, accurate current sensing is available using external current sense resistors in series with the synchronous rectifier. The synchronous rectifier may be used for current sensing to save power.
The MAX1844 is available in a 20-pin QSOP package. Prices for the MAX1844 start at $2.60 (1000-up, FOB USA). A preassembled MAX1844EVKIT (evaluation kit) is available with recommended external components to reduce design time.
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