ADI LTC3869IGN-2#TRPBF

Step-DownБак4 В ~ 38 В

Overview

Dual, 2-Phase Synchronous Step-Down DC/DC Controllers The LTC�3869 is a high performance dual synchronous step-down switching regulator controller that drives all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 780kHz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages out-of-phase. OPTI-LOOP� compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3869IGN-2#PBF features a precision 0.6V reference and a power good output indicator. A wide 4V to 38V input supply range encompasses most battery chemistries. Independent TK/SS pins for each controller ramp the output voltage during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode� operation, pulse-skipping mode, or continuous inductor current mode and allows the IC to be synchronized to an external clock.

Top Gate Off to Bottom Gate On Delay CLOAD = 3300pF Each Driver (Note 6) Synchronous Switch-On Delay Time Bottom Gate Off to Top Gate On Delay CLOAD = 3300pF Each Driver (Note 6) Top Switch-On Delay Time Minimum On-Time (Note 7)

Features

Dual, 180° Phased Controllers Reduce Required Input Capacitance and Power Supply Induced Noise

Accurate Multiphase Current Matching

RSENSE or DCR Current Sensing

±0.75% 0.6V Output Voltage Accuracy

Phase-Lockable Fixed Frequency 250kHz to 780kHz

High Efficiency: Up to 95%

Dual N-channel MOSFET Synchronous Drive

Wide VIN Range: 4V to 38V (40V Max) Operation

Wide VOUT Range: 0.6V to 12.5V Operation

Adjustable Soft-Start Current Ramping or Tracking

Foldback Output Current Limiting

Output Overvoltage Protection

Power Good Output Voltage Monitor

5V Low Dropout Regulator

Small 28-Lead QFN and Narrow SSOP Packages

Applications

Server Systems

Telecom Systems

Industrial and Medical Instruments

High Power Battery-Operated Devices

DC Power Distribution Systems