Features

• Flexible Power Supply System Providing Three Outputs Over a Wide Input Voltage Range
• Two High Voltage Synchronous Buck Regulators
• 3V to 42V Input Voltage Range
• Output Currents Up to 2.5A and 1.5A
• High Efficiency Up to 93%
• One Low Voltage Synchronous Buck Regulator
• 2.6V to 5.5V Input Voltage Range
• Output Current Up to 1.8A and 95% Efficiency
• Resistor Programmable and Synchronizable from 250kHz to 2.2MHz Switching Frequency
• Low Ripple Burst Mode® Operation
• 30μA I_Q at 12V_IN to 3.3V_OUT2
• Output Ripple <15mV
• Programmable Power-On Reset
• Power Good Indicators
• 2-Phase Clock Reduces Input Current Ripple
• Available in Thermally Enhanced 40-Lead QFN (6mm × 6mm) Package

Typical Application

Description

The LT®8601 is a triple channel, current mode, monolithic buck switching regulator with a programmable power-on reset. All regulators are synchronized to a single oscillator with an adjustable frequency from 250kHz to 2.2MHz. The LT8601 can be configured for micropower Burst Mode or Pulse-Skipping operation at light load. Micropower operation results in quiescent current of 30μA with all three regulators operating as shown in the application below with no load applied.

The high voltage channels are synchronous buck regulators that operate from an input of 3.0V to 42V. The output currents are up to 1.5A (OUT1) and 2.5A (OUT2). The low voltage channel operates from an input of 2.6V to 5.5V. Internal synchronous power switches provide high efficiency with output currents up to 1.8A. The LT8601 uses a 2-phase clock with channel 1 operating 180° from channels 2 and 3 to reduce input ripple current on both HV and LV inputs. All channels have cycle-by-cycle current limit, providing protection against shorted outputs. Thermal shutdown provides additional protection.

The LT8601 is available in a 40-lead 6mm × 6mm QFN package.