IR3891 Dual-Output SupIRBuck® Voltage Regulator


International Rectifier's IR3891 SupIRBuck® integrated dual-output voltage regulators are designed for space-constrained netcom, server and storage applications

The IR3891 dual-output device is optimized for single-rail operations from 5 V to 12 V inputs, or 1 V to 21 V input with external 5 V bias. The IR3891 is available in a compact 5 x 6 mm PQFN package, and offers an ultra-compact solution for applications requiring up to 4 A per channel, and up to 6 A per channel in as little as 165 mm². The IR3891 features a proprietary modulator scheme that enables jitter and noise-free operation to allow higher frequency and bandwidth operation for better transient response, and fewer output capacitors to reduce overall system size. Other key features include interleaved phases to reduce input capacitance, powertrain isolation to eliminate crosstalk, and sequencing capability on channel 2.

Features
  • Single 5 V to 21 V application
  • Wide input voltage range from 1 V to 21 V with external VCC
  • Output voltage range 0.5 V to 0.86 PVIN
  • Enhanced line/load regulation with feed-forward
  • Programmable switching frequency up to 1.5 MHz
  • Internal digital soft-start
  • Enable input with voltage monitoring capability
  • Thermally-compensated current limit and hiccup mode over-current protection
  • External synchronization with smooth clocking
  • Precision reference voltage (0.5 V ±1%)
  • Sequence pin for sequencing applications
  • Integrated MOSFETs, drivers and bootstrap diode
  • Thermal shut-down
  • Open feedback-line protection
  • Over-voltage protection
  • Interleaved phases to reduce input capacitors
  • Monotonic start-up
  • Operating junction temperature 40ºC to < 125ºC
  • Small size 5 mm x 6 mm PQFN
  • Lead halogen-free, and RoHS compliant

IR3891 Regulator

Manufacturer Part Number Description Available Quantity Datasheets
IR3891MTRPBF IC REG BUCK SYNC ADJ 4A 31PQFN 4380