Features

• Flexible Power Supply System Providing Four Outputs with a Wide Input 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%
• Two Low Voltage Synchronous Buck Regulators:
  2.6V to 5.5V Input Voltage Range
  Output Currents Up to 1.8A and 94% Efficiency
• Resistor Programmable and Synchronizable 250kHz to 2.2MHz Switching Frequency
• Low Ripple Burst Mode® Operation:
  30μA I_Q at 12V_IN
  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®8602 is a quad 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 LT8602 can be configured for micropower Burst Mode operation or pulse-skipping operation at light load. Micropower operation results in quiescent current of 30μA with all four regulators operating in the application below.

The high voltage channels are synchronous buck regulators that operate from an input of 3V to 42V. The output currents are up to 1.5A (OUT1) and 2.5A (OUT2). The low voltage channels operate from an input of 2.6V to 5.5V. Internal synchronous power switches provide high efficiency with output currents up to 1.8A. The LT8602 uses a 2-phase clock with channels 1 and 3 operating 180° from channels 2 and 4 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 LT8602 is available in a 40-lead 6mm × 6mm QFN package.