The LTC3372 features a 60V synchronous buck switching regulator controller followed by four configurable synchronous monolithic buck regulators. According to Analog, this combination provides up to five high efficiency low quiescent current outputs in a single IC.
The LTC3372’s buck controller operates over a 4.5V to 60V input voltage range and drives an all N-channel MOSFET power stage. Its output can be programmed to either 3.3V or 5V and can generate an output current up to 20A. The controller output is typically used to feed the four monolithic buck regulators. Each monolithic buck channel can be programmed to regulate an output voltage as low as 0.8V with a configurable output current up to 4A. Eight 1A integrated power stages are programmed by the C1-C3 pins into one of eight unique configurations, from a quad 2A buck to a dual 4A buck. This allows only one inductor per channel.
With just the high voltage controller enabled, the device draws 15µA from a 12V input supply while regulating the output to 5V at no load. Each monolithic buck regulator adds only 8µA of additional IQ per channel enabled. The LTC3372’s monolithic buck switching frequency can be programmed from 1MHz to 3MHz and can be synchronised to an external clock while the buck controller switches at 1/6 of this frequency. Additional features include foldback current limiting, soft-start, short-circuit protection and output overvoltage protection.
The LTC3372 is available from stock in a thermally enhanced 48-pin 7mm x 7mm QFN package. E and I grades are specified over an operating junction temperature range of –40°C to 125°C, and the H grade features operation from –40°C to 150°C.
