Texas Instruments LM5161 Synchronous Buck/Fly-Buck Converter

Texas Instruments LM5161 Synchronous Buck/Fly-Buck Converter is a 100V, 1A synchronous step-down converter with integrated high-side and low-side MOSFETs. The constant-ON-time control scheme requires no loop compensation and supports high step-down ratios with a fast transient response. An internal feedback amplifier maintains ±1% output voltage regulation over the entire operating temperature range. The ON-time varies inversely with input voltage resulting in nearly constant switching frequency. Peak and valley current limit circuits protect against overload conditions. The under-voltage lockout (EN/UVLO) circuit of the Texas Instruments LM5161 provides independently adjustable input under-voltage threshold and hysteresis.

Features

  • Wide 4.5V to 100V input voltage range
  • Integrated high-side and low-side switches
    • No Schottky diode required
  • 1A maximum load current
  • Constant ON-time control
    • No external loop compensation
    • Fast transient response
  • Selectable DCM buck operation at light load
  • CCM option supports multi-output Fly-Buck™
  • No external ripple circuit needed (at FPWM = 0)
  • Nearly constant switching frequency
  • Frequency adjustable up to 1MHz
  • Programmable soft-start time
  • Prebias start-up
  • Peak current limiting protection
  • Adjustable input UVLO and hysteresis
  • ±1% feedback voltage reference
  • Thermal shutdown protection

Applications

  • Industrial programmable logic controller
  • IGBT gate drive bias supply
  • Telecom DC/DC primary and secondary side bias
  • E-meter power line communication
  • Low-power (< 12W), isolated DC-DC (fly-buck)

Functional Block Diagram

Block Diagram - Texas Instruments LM5161 Synchronous Buck/Fly-Buck Converter
Opublikowano: 2016-10-20 | Zaktualizowano: 2022-03-11