G5207 Global Mixed-mode Technology Inc. 24V Input Voltage-Mode Buck PWM Controller Features General Description Drives Two N-Channel MOSFETs Operates at 5V Supply Voltage Voltage-Mode PWM Control Fast Transient Response 0.8V, 2% Accuracy Reference Voltage Internal Soft Start Constant 300kHz Switching Frequency Over-Current Fault Monitors by Using Low-Side MOSFET RDS(ON) Output Under-Voltage Protection The G5207 provides complete control and protection for a DC-DC converter for high power applications. It is designed to drive two N-channel MOSFETs in a synchronous-rectified buck topology. The G5207 integrates all of the control, and protection functions into a single package. The G5207 provides simple, single feedback loop, voltage-mode control with fast transient response. It includes a 300KHz free-running triangle-wave oscillator. The error amplifier features a 15MHz gain-bandwidth product which provides high converter bandwidth for fast transient performance. The resulting PWM duty ratio ranges from 0% to 80%. The reference voltage is 0.8V, 2% accuracy. Applications 16V to 30V Input High Power DC-DC Regulators Low-Voltage Distributed Power Supplies The G5207 has internal soft start and executes cycle-by-cycle current limit during soft start interval. The G5207 monitors the current by using the RDS(ON) of the low-side MOSFET which eliminates the need for a current sensing resistor. The under-voltage protection function monitors voltage at FB pin. The over-current and under-voltage events after soft-start interval trigger hiccup mode protection. Ordering Information ORDER NUMBER G5207P11U Note: P1: SOP-8 1: Bonding Code U: Tape & Reel MARKING TEMP. RANGE PACKAGE (Green) G5207 -40°C~ +85°C SOP-8 Pin Configuration Typical Application Circuit 5V G5207 16~30V G5207 BOOT 1 10Ω 8 220µF LX VCC BOOT 4.7µF UGATE 2 7 OCSET ROCSET OCSET GND 6 3 FB SHDN LGATE 4 5 VCC FB UGATE 0.1µF 6µH VO=13.5V LX LGATE 2000µF 620Ω 10nF GND SOP-8 39Ω TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 1.4 Jul 18, 2011 1