OB2007

GENERAL DESCRIPTION

OB2007 is a high performance and highly integrated secondary side synchronous rectification controller used for secondary side rectification in switch mode power supply system. It drives a much lower voltage drop N-channel MOSFET to emulate the traditional diode rectifier at the secondary side of flyback converter, which can reduce heat dissipation, increase output current capability and efficiency, and simplify thermal design. It can support wide range of system output voltage 3V~21V.

It is suitable for multiple mode applications including discontinuous conduction mode (DCM), quasi-resonant mode (QR) and continuous conduction mode (CCM). The drain-to-source voltage of SR MOSFET is sensed to control the turn on and off of the SR MOSFET. In addition, to reduce SR falling time further, soft gate is implemented in OB2007, which would pull down the gate voltage level before being turned off  thoroughly.

OB2007 is offered in SOT23-6 package.

FEATURES

■   Secondary-side synchronous rectification controller for 3V~21V output system

■   Up to 180V VD pin high voltage tolerance

■   Self-supplying for operation without the use of an auxiliary winding

■   Suitable for DCM, QR and CCM operation

■   Soft gate drive for fast turn-off

■   Accurate secondary side MOSFET Vds sensing

■   Adaptive off time control effectively avoid the ring impact induced by parasitic elements

■   3A/2A peak current sink/source driver capability

■   VDD UVLO protection

APPLICATIONS

■   AC/DC 3V~21V adaptors

■   Low voltage rectification circuits 

TYPICAL APPLICATION