Linear Technology's LTC3890 and LTC3890-1 are high voltage, dual output synchronous step-down DC/DC controllers that draw only 50µA when one output is active and 60µA when both outputs are enabled. With both outputs shut down, the LTC3890 and LTC3890-1 draws a mere 14µA.
The 4V to 60V input supply range is designed to protect against high voltage transients, continue operation during automotive cold crank, and cover a broad range of input sources and battery chemistries. Each output can be set from 0.8V to 24V at output currents up to 20A with efficiencies as high as 95%, making it well suited for 12V or 24V automotive, heavy equipment, industrial control, robotics and telecom applications.
The LTC3890 and LTC3890-1 have powerful 1.1Ω on-chip MOSFET gate drivers. They operate with a selectable fixed frequency between 50kHz and 900kHz and can be synchronized to an external clock from 75kHz to 850kHz with its phased-locked loop (PLL). Output current sensing is accomplished by measuring the voltage drop across the output inductor (DCR) for the highest efficiency or by using an optional sense resistor. Current foldback limits MOSFET heat dissipation during overload conditions.
- Wide input voltage range: 4V to 60V
- 50µA quiescent current with one output active and 60µA with both outputs active
- 14µA shutdown current
- Wide output voltage range: 0.8V to 24V
- Synchronous rectification for up to 95% efficiency
- DCR or Rsense current sense
- Selectable low ripple burst mode operation, pulse skipping, or continuous operation
- Selectable fixed operating frequency from 50kHz to 900kHz
- Synchronizable operating frequency from 75kHz to 850kHz with PLL
- Current mode control for fast transient response and easy lop compensation
- Adjustable soft-start
- ±1% voltage reference accuracy over -40°C to 125°C
- Output overvoltage and overcurrent foldback protection