New Industry Products

42V, 5A Synchronous Step-Down DC-DC with 2.5µA Quiescent Current

November 26, 2019 by Paul Shepard

The LT®8636 synchronous step-down dc-dc regulator from Analog Devices features the company's Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. Peak current mode control with a 30ns minimum on-time also supports high step-down ratios at high switching frequencies.

This step-down regulator is designed for use in automotive systems, industrial equipment and general-purpose step-down applications.

The LT8636's ultralow 2.5µA quiescent current—with the output in full regulation—enables applications requiring highest efficiency at very small load currents. A CLKOUT pin enables synchronizing other regulators to the LT8636.

Burst Mode operation enables ultralow standby current consumption, forced continuous mode can control frequency harmonics across the entire output load range, or spread spectrum operation can further reduce EMI emissions. Soft-start and tracking functionality is accessed via the TR/SS pin, and an accurate input voltage UVLO threshold can be set using the EN/UV pin.

Summary of Features:

  • Silent Switcher ® Architecture
    • Ultralow EMI Emissions
    • Optional Spread Spectrum Modulation
  • High Efficiency at High Frequency
    • Up to 96% Efficiency at 1MHz, 12VIN to 5VOUT
    • Up to 95% Efficiency at 2MHz, 12VIN to 5VOUT
  • Wide Input Voltage Range: 3.4V to 42V
  • 5A Maximum Continuous, 7A Peak Output
  • Ultralow Quiescent Current Burst Mode® Operation
    • .5µA IQ Regulating 12VIN to 3.3VOUT
    • Output Ripple < 10mVP-P
  • Fast Minimum Switch On-Time: 30ns
  • Low Dropout Under All Conditions: 100mV at 1A
  • Forced Continuous Mode
  • Adjustable and Synchronizable: 200kHz to 3MHz
  • Output Soft-Start and Tracking
  • Small 20-Lead 4mm × 3mm LQFN Package
  • AEC-Q100 Qualification in Progress