GaN Power Chip U8722X Series Welcomes U8722FE with 65W Power Output
U8722FE
GaN power chipU8722Xfamily welcomes a new member –U8722FE, with a recommended maximum output power of65W, integratingMOSwith a voltage rating of700V, usingESOP-7package, with 5000 pieces per reel, and an integratedBoostpower supply circuit, making it very suitable for applications with wide output voltage ranges.
The GaN power chip U8722FE adopts a peak current control mode, allowing it to adaptively operate in QR and frequency reduction modes, thus optimizing efficiency across the full load power range. Under full load and heavy load conditions, the system operates in QR mode, significantly reducing switching losses. The chip adjusts the number of valleys based on the FB voltage value, and to avoid fluctuations in the FB voltage at critical loads causing valley number jumps and noise, the U8722FE employs a valley locking mode to stabilize the number of conducting valleys under certain load conditions, ensuring a noise-free system.
As the load gradually decreases, the number of conducting valleys increases. When the number of valleys exceeds 6, the system stops detecting valley voltage, entering frequency reduction mode, further lowering the switching frequency to reduce switching losses and optimize system efficiency at light loads.
U8722FE
Due to parasitic capacitance of the primary power switch, parasitic capacitance of the transformer, and reverse recovery of the secondary rectifier, voltage spikes occur across the sampling resistor at the moment the power switch is turned on. To prevent the drive signal from being erroneously turned off,the GaN power chipU8722FEintegrates a leading edge blanking function. WithinTLEB_OCP (typical value 300 ns)after the switch is turned on, the peak current comparator will not turn off the power switch.
In the case of abnormal overcurrent protection (AOCP), to ensure system reliability, when the CS pin voltage reaches the AOCP protection threshold VCS_AOCP (typical value -1.2V), the leading edge blanking time is further reduced to TLEB_AOCP. When the VDD voltage reaches the protection threshold VVDD_OVP (typical value 39V), the GaN power chip U8722FE stops switching actions and enters automatic restart protection mode. The chip integrates a clamp voltage regulator, effectively preventing damage to the chip.