The new DCR sensing technique reduces the switching jitter normally associated with low DCR resistance applications. DCR temperature compensation maintains a constant and accurate current limit threshold over a broad temperature range.
The LTC3866 operates from a 4.5 V to 38 V input voltage range that encompasses a wide range of applications including most intermediate bus voltages and battery voltages. Strong onboard N-channel MOSFET gate drivers allow the use of high power external MOSFETs, DrMOS devices or power blocks for an output current of up to 40 A, with output voltages ranging from 0.6 V to 5 V. The LTC3866 can be paralleled for even higher power multiphase applications.
An onboard differential amplifier provides remote output voltage sensing of both the positive and negative terminals, enabling high accuracy regulation independent of IR losses (up to ±500 mV) in trace runs. A low current sense threshold from 10 mV to 30 mV can be selected. The fixed operating frequency is adjustable from 250 kHz to 770 kHz or can be synchronized to an external clock. Additional features include an internal bias voltage regulator, soft start or tracking, overvoltage protection, soft short-circuit recovery, current limit foldback, thermal shutdown and external V CC control.
More information about the LTC3866 current mode synchronous step-down DC/DC controller at www.linear.com/product/LTC3866