PL3900 100V Multi-Phase Synchronous Buck/Boost Controller

1 Features

2-Phase Operation Reduces Required Input and

Output Capacitance and Power Supply Induced

Noise

Synchronous Operation for Highest Efficiency and

Reduced Heat Dissipation

Wide VIN Range:4.5V to 56V (Sense Pin 60V Abs

Max ) in Boost mode and Operates Down to 2.5V

After Start-Up ，4.5V to 96V (Vbias Pin 100V Abs

Max ) in Buck mode

Output Voltage Up to 96V(Boost mode) and

56V(Buck mode)

±1% 1.2V Reference Voltage

RSENSE or Inductor DCR Current Sensing

CV/CC Mode control (Constant voltage and

constant current)

Phase-Lockable Frequency (75kHz to 850kHz).

Programmable Fixed Frequency (50kHz to 900kHz)

Power Good Output Voltage Monitor

Internal LDO Powers Gate Drive from VBIAS or

EXTVCC

Thermally Enhanced Low Profile 28-Pin 4mm ×

5mm QFN Package

2 Applications

consumer

Industrial

Automotive

Medical

3 Description

      The PL3900 is a high performance Multi-Phase single output synchronous buck/boost converter controller that drives two N-channel power MOSFET stages out-of-phase. Multiphase operation reduces input and output capacitor requirements and allows the use of smaller inductors than the single-phase equivalent.Synchronous rectification increases efficiency, reduces power losses and eases thermal requirements, enabling high power boost applications.

A 4.5V to 56V (boost mode) and 4.5V to 96V (buck mode) input supply range encompasses a wide range of system architectures and battery chemistries.

When biased from the output of the converter or another auxiliary supply, the PL3900 can operate from an input supply as low as 2.5V after start-up. The

operating frequency can be set for a 50kHz to 900kHz range or synchronized to an external clock using the internal PLL. Multi-Phase operation allows the

PL3900 to be configured for 2-, 3-, 4-, 6- and 12-phase operation.

  The SS pin ramps the output voltage during start-up.

 The PLLIN/MODE pin selects Burst Mode operation,pulse-skipping mode or forced continuous mode atlight loads.

4 Website：www.baitaishengshi.com

5Typical Application Schematic