New Industry Products

60V Low IQ Buck Controller Plus 4-Channel 8A Configurable Buck DC-DCs

August 21, 2018 by Paul Shepard

Analog Devices, Inc. has announced the Power by Linear™ LTC3372, a highly-integrated power management solution for systems that require multiple low voltage outputs generated from an input voltage as high as 60V. The LTC3372 features a 60V synchronous buck switching regulator controller followed by four configurable synchronous monolithic buck regulators.

This combination provides up to five high-efficiency low quiescent current outputs in a single IC, designed for automotive, industrial and medical applications.

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.

The LTC3372 offers a low IQ solution well-suited for battery-powered or automotive applications in which one or more power supply rails are always on. 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 synchronized 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 × 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.

Summary of LTC3372 features:

  • High-Voltage Buck Controller: VIN = 4.5V to 60V, VOUT = 5V/3.3V
  • Low-Voltage Buck Regulators: VINA-H = 2.25V to 5.5V, VOUT1-4 ≥8V
  • 8 ×1A LV Buck Integrated Power Stages, Configurable as 2, 3 or 4 Output Channels
  • 8 Unique Output Configurations (1A to 4A per Channel)
  • Low Total No-Load Input Supply Current (IQ)
    • 15μA HV Controller Only (5VOUT)
    • 23μA HV Controller Only (3.3VOUT)
    • 9μA Per Additional LV Regulator Channel
  • 1MHz to 3MHz Operation (HV Controller Runs at 1/6 Frequency)
  • Programmable Frequency or Synchronizable to External Clock
  • Programmable Watchdog & Power-On Reset Delay
  • IC Die Temperature Monitor Output
  • Thermally-Enhanced 48-Pin7mm × 7mm QFN Package

The LTC3372 is in full production with pricing starting at $5.75 in lots of 1,000.