VPSC VPS8703

VPS8703 is a transformer driver specifically designed for micro-power isolated power supplies with small form factor and low standby power consumption. With only simple input/output filter capacitors, an isolation transformer, and a rectifier circuit as peripheral components, it enables an isolated power supply with 6.5~30V input voltage, multiple output voltages, and output power up to 15W.

The VPS8703 integrates two N-channel power MOSFETs and two P-channel power MOSFETs internally, configured in a bridge topology. The on-chip oscillator provides a pair of high-precision complementary signals, ensuring highly symmetrical drive of the two power MOSFET paths and preventing transformer core saturation during operation.

The VPS8703 integrates frequency modulation and multiple protection features. Frequency adjustment can be implemented for different application requirements, while an internal high-precision dead-time control circuit ensures no shoot-through occurs under various operating conditions. Integrated overcurrent detection protection and over-temperature protection prevent device damage under abnormal conditions such as output short-circuit.

The VPS8703 is a full-bridge topology DC-DC isolated switching power supply integrated controller. The bridge drive topology requires fewer transformer windings and reduces cost. It supports 6.5V~30V applications with strong compatibility. When overcurrent is detected, the power transistor current is clamped and limited, ensuring the chip operates within its safe operating area while protecting peripheral components from high-current stress.

The operating frequency can be set via the CLK pin (default frequency when left floating), and a dead-band time t_BBM is designed between the two drive signals to prevent shoot-through, reduce drain-source voltage at power transistor turn-on, and minimize switching losses.

The chip can be enabled or disabled via the EN pin. When EN is pulled high (pulled high internally when left floating), the chip operates normally; when EN is pulled low, the chip stops working, achieving ultra-low standby power consumption.

• Full-bridge topology
• High integration, minimal external components
• Integrated 30V / 0.25Ω NMOS
• Integrated 30V / 0.60Ω PMOS
• 6.5 - 30V input voltage range
• Input surge voltage up to 40V
• Programmable switching frequency
• Enable shutdown function
• Continuous short-circuit protection, over-temperature protection, auto-recovery
• Operating temperature range: -40°C ~ +125°C
• ESOP8 enhanced thermal dissipation package

• Low-power isolated power supply for CAN/RS-485/RS-232/SPI/I²C
• Process control
• Precision instruments/medical instruments
• Distributed power/radio power/telecom power
• Low-noise isolated USB power supply
• Low-noise filament power supply
• IGBT gate driver power supply