VPSC VPS8702

VPS8702/S 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, it can realize an isolated power supply with 3–6V input voltage, multiple output voltages, and output power up to 3W. The VPS8702/S integrates two N-channel power MOSFETs and two P-channel power MOSFETs internally, connected in a bridge configuration. An on-chip oscillator provides a pair of high-precision complementary signals, which effectively ensures high symmetry of the two power MOSFET drive paths and prevents magnetic flux imbalance during operation. The VPS8702/S incorporates multiple protection mechanisms. A high-precision dead-time control circuit is built in to prevent shoot-through under all operating conditions. Overcurrent protection and over-temperature protection are also integrated to prevent device damage under abnormal conditions such as output short circuits.

The VPS8702/S is a DC-DC isolated switching power supply integrated controller suitable for full-bridge topology. The bridge drive topology requires fewer transformer windings, resulting in lower cost. It supports 3–6V applications with strong compatibility. When the current is excessive, clamping limits the power transistor current, ensuring both the chip itself operates within the safe operating area and protecting peripheral components from high-current stress. A dead-band time t_BBM is designed between the two drive signals to prevent shoot-through while also reducing the drain-source voltage at turn-on and minimizing switching losses. The chip can be enabled or disabled via the EN pin. When EN is pulled high (or left floating, as it is pulled high internally by default), the chip operates normally. When EN is pulled low, the chip stops operating, achieving ultra-low standby power consumption.

• Full-bridge topology
• High integration, minimal external components
• Built-in 0.13Ω NMOS
• Built-in 0.25Ω PMOS
• 0.8A current clamp limit
• 3 - 6V input voltage range
• Input surge voltage up to 10V
• Input overvoltage protection
• Sustained short-circuit protection, over-temperature protection, auto-recovery
• Operating temperature range: -40°C ~ +125°C

• 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 drive power supply