EG3525S

The EG3525S integrates a 5.1V voltage reference, a 100Hz–500KHz wide-range oscillator, a soft-start circuit, an error amplifier, a PWM comparator, an undervoltage lockout circuit, and a power transistor output driver. The EG3525S features synchronous clock functionality, supporting both master/slave operation and synchronization with an external system clock, providing maximum design flexibility. Dead-time adjustment is achieved by connecting a resistor between the CT pin and the Discharge pin. The EG3525S incorporates an internal soft-start circuit. Connecting a timing capacitor to pin 8 enables PWM soft-start operation. During power-up, the soft-start timing capacitor is charged by an internal 50μA constant current source, causing the capacitor voltage to rise gradually from zero to Vref while the PWM output increases progressively from zero to the maximum duty cycle required for regulation. The soft-start sequence completes when the capacitor voltage reaches Vref. When the fault circuit asserts the Shutdown signal, it affects both the output stage and the soft-start circuit. When the signal on Shutdown (pin 10) is high, the EG3525S output is inhibited and the soft-start capacitor begins to discharge. If the high level persists, the soft-start capacitor will fully discharge and the soft-start sequence will not reinitiate until the shutdown signal is released. The Shutdown pin must not be left floating; it should be reliably connected to ground through a resistor to prevent external interference from coupling into the EG3525S and disrupting normal operation.

Applications

• Inverter power supplies
• High-power high-frequency switching power supplies
• DC pulse-width modulation speed control systems
• UPS power supplies
• DC/DC converters
• High-power chargers

Key features

• Wide operating voltage range: +8V ~ +35V
• Built-in 5.1V reference voltage, ±2% accuracy
• Wide oscillation frequency range: 100Hz ~ 500KHz
• External oscillator synchronization
• Adjustable dead time
• Built-in soft-start circuit
• Input undervoltage lockout
• PWM latch function, inhibits multiple pulses
• Dual-channel sink and source current drive capability
• Package: SOP-16 and DIP-16