Highly Integrated, Compact Footprint
• Eliminates switching losses in InnoSwitch4 primary switch
• Captures and recycles leakage inductance energy
• Dramatically improves power supply efficiency
• Interfaces seamlessly with InnoSwitch4
• Powered directly from InnoSwitch4 BYPASS pin
• Self-biased at start-up
• Operates in both DCM and CCM modes
• Robust 750 V PowiGaN switch (CPZ1075M / CPZ1076M)
Advanced Protection / Safety Features
• Integrated temperature sensing and hysteretic thermal shutdown
Green Package
• Halogen free and RoHS compliant
Applications
• High density flyback designs up to 220 W
Description
The ClampZero™ IC pairs with the InnoSwitch™4 family of ICs to
eliminate energy wasted due to switching losses in the clamp and
primary switch. This dramatically improves power supply efficiency –
easily exceeding 95% - while maintaining the flexibility and low
component count of the flyback architecture.
The ClampZero IC is an active clamping circuit which recycles
otherwise wasted leakage inductance energy. The ClampZero
incorporates a high-side power switch and level shifted self-biased
controller which receives communication from a low-side transceiver
connected to the InnoSwitch4 primary controller
By ensuring zero voltage switching across all line and load conditions
and in both CCM and DCM operating modes, ClampZero combines with
InnoSwitch4 to implement a highly flexible active clamp flyback
solution. In a typical application paired with the InnoSwitch4 IC, the
low switching losses permit use of a high switching frequency,
minimizing the physical size of the transformer and resulting in an
extremely small PCB footprint.
Zero-voltage switching is achieved by precise timing between the
turn-off of the ClampZero and turn-on of the InnoSwitch4 power
switch, which completely removes turn-on losses. The overall effect of
this synchronized switching, along with the InnoSwitch4 PowiGaN
switch with zero turn-off losses, is a flyback converter with zero
primary clamp losses and zero power switch switching losses enabling
high density, heat sinkless flyback designs up to 220 W.