ZXGD3109N8 (Obsolete)

Description

The ZXGD3109N8 is intended to drive a MOSFET configured as an ideal diode replacement. The device is comprised of a high voltage detector stage and gate driver. The detector monitors the voltage between the drain and the source of the MOSFET and if this voltage is less than the turn on threshold voltage of the controller a positive voltage is applied to the MOSFET’s Gate pin. As the load current decays to zero and the voltage between the drain and source of the MOSFET increases beyond the turn off threshold value MOSFET is rapidly turned off.

Intelligent features of this IC are the Minimum off time (T_OFF) and Minimum on time (T_ON), these features blanks the noise generated during the turn on and turn off instances of the power FET. Light load detection (LLD) for improved efficiency at light and no load, where synchronous rectification is no more beneficial. Other features include, under voltage lock out (UVLO) and low turn off threshold voltage for improved efficiency.

Feature(s)

• Frequency of Operation up to 500kHz
• Suitable for Discontinuous (DCM) and Critical (CrCM) Conduction Mode
• Minimum On-Time and Off-Time to Reduce Turn-On/Off Oscillations
• Intelligent Light Load Detection and Sleep Mode
• Turn-Off Propagation Delay Time of 30ns Typically
• Drain Voltage Rating of 200V
• Recommended Operating Voltage from 4.5V up to 12V
• Source and Sink Current of 2A and 4A Respectively
• Low Component Count

Application(s)

Flyback Converters in:

• Power Adaptors
• Auxiliary Power Supplies
• PoE Power Devices

Resonant Converters in:

• High Power Adaptors
• 85+/90+ Compliant ATX and Server Power Supplies