DC/DC Controller Uses Differential Output Sensing

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For achieving tight output regulation, the LTC3867 fixed frequency synchronous step-down DC/DC controller employs nonlinear control, differential output voltage sensing, and clock synchronization. Nonlinear control minimizes the output voltage excursion during load transient events by increasing the operating frequency, allowing the device to recover from a large load step in only a few cycles. This cuts the maximum deviation from nominal by as much as 50% compared to traditional controllers. Other features include a 4V to 38V input range, N-channel MOSFET gate drivers, load currents up to 25A, an output voltage range from 0.6V to 14V, a 65-ns minimum on-time, selectable operating frequency from 200 kHz to 1.2 MHz or synchronized to an external clock, CR temperature compensation, a bias voltage LDO, soft-start or tracking, adjustable current limit, soft recovery from an output over-current condition, overvoltage protection, external VCC control, and a ±1% reference voltage accuracy over a -40°C to +125°C operating junction temperature range. Available in a 4 mm x 4 mm QFN-24 package, price starts at $2.76 each/1,000. LINEAR TECHNOLOGY CORP., Milpitas, CA. (800) 454-6327.