ClampZero Family Active Clamp IC with Integrated High-Voltage Switch Pairs with InnoSwitch4 Family of Offline Switcher ICs Product Highlights ClampZero D Highly Integrated, Compact Footprint Eliminates switching losses in InnoSwitch4 primary switch Captures and recycles leakage inductance energy HS S2 Dramatically improves power supply efficiency Interfaces seamlessly with InnoSwitch4 BP2 Powered directly from InnoSwitch4 BYPASS pin High-Voltage Self-biased at start-up LS DC Input Operates in both DCM and CCM modes Advanced Protection / Safety Features Integrated temperature sensing and hysteretic thermal shutdown InnoSwitch4-CZ Green Package Halogen free and RoHS compliant PI-9086c-112320 Applications High density flyback designs up to 135 W Figure 1. Typical Application schematic. Description The ClampZero IC pairs with the InnoSwitch4 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 Figure 2. MinSOP-16A Package with Creepage for High-Side Driver. 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 ClampZero + InnoSwitch4 Output Power Table InnoSwitch4 to implement a highly flexible active clamp flyback solution. In a typical application paired with the InnoSwitch4 IC, the 85-265 VAC low switching losses permit use of a high switching frequency, 3 Product minimizing the physical size of the transformer and resulting in an 1 2 Adapter Open Frame extremely small PCB footprint. CPZ1061M 75 W 85 W Zero-voltage switching is achieved by precise timing between the turn-off of the ClampZero and turn-on of the InnoSwitch4 power CPZ1062M 120 W 135 W switch, which completely removes turn-on losses. The overall effect of this synchronized switching, along with the InnoSwitch4 PowiGaN Table 1. Output Power Table. switch with zero turn-off losses, is a flyback converter with zero Notes: 1. Minimum continuous power in a typical non-ventilated enclosed typical size primary clamp losses and zero power switch switching losses enabling adapter measured at 40 C ambient. Max output power is dependent on the high density, heatsinkless flyback designs up to 135 W. design. With condition that package temperature must be < 125 C. 2. Minimum peak power capability. 3. Package: MinSOP-16A. www.power.com November 2020 This Product is Covered by Patents and/or Pending Patent Applications. S1 BP1 INClampZero DRAIN PRIMARY BYPASS (D) (BP2) REGULATOR BP2/UV BP2 PIN UNDERVOLTAGE + V BP2 V V BP2 BP2(H2) THERMAL SHUTDOWN V SHUNT2 Power BP2 Switch HIGH-SIDE RECEIVER AND DRIVER LOGIC DRIVER SOURCE (S2) PRIMARY BYPASS (BP1) DRIVE LINK TO HIGH-SIDE IN SOURCE (S1) PI-8553-110920 Figure 3. Block Diagram. 2 Rev. C 11/20 www.power.com