U3220E

U3220E is a high-performance, low-cost PWM control power switch designed for off-line low-power boost, buck, and buck-boost applications. It features a simple peripheral circuit with a minimal component count. The device integrates a high-voltage startup module and a high-voltage-rated MOSFET, enhancing the system's surge withstand capability. Unlike conventional PWM power switches, the U3220E has no fixed internal clock to drive the MOSFET; instead, the switching frequency automatically adjusts in response to load variations. The device employs multi-mode PWM control technology, which effectively simplifies peripheral circuit design, improves line and load regulation, and eliminates audible noise during system operation. In addition, the internal peak current detection threshold automatically adjusts according to actual load conditions, significantly reducing standby power consumption under no-load state. The U3220E integrates comprehensive protection features with auto-recovery capability, including VDD undervoltage protection, cycle-by-cycle current limiting, output overvoltage protection, overtemperature protection, overload protection, and VDD overvoltage protection.

Applications

• Telecom 90V power systems
• Ethernet PoE
• Industrial control
• Inverter systems

Key features

• Input voltage range: 12~100V (adjustable output)
• Integrated 7A/100V (peak 10A/100V) MOSFET
• Integrated 180V high-voltage startup circuit
• Multi-mode control for silent operation
• Supports boost, buck, and buck-boost topologies
• Default output 14.3V (FB pin floating)
• Standby power consumption below 50 mW
• Excellent line regulation and load regulation
• Integrated soft-start circuit
• Internal protection features: overload protection, cycle-by-cycle current limiting, output OVP, VDD OVP/UVP, and voltage clamp protection