TPS5110

TPS5110 SLVS025B − APRIL 2002 − REVISED JULY 2004 SYNCHRONOUSĆBUCK PWM CONTROLLER WITH NMOS LDO CONTROLLER FEATURES D Switching Mode Step-Down dc-to-dc Controller With Fast LDO Controller D Input Voltage Range Switcher: 4.5 V to 28 V LDO: 1.1 V to 3.6 V D Output Voltage Range Switcher: 0.9 V to 3.5 V LDO: 0.9 V to 2.5 V D Synchronous for High Efficiency D Precision VREF (±1 %) D PWM Mode Control: Max. 500-kHz Operation D High-Speed Error Amplifier D Overcurrent Protection With Temperature Compensation Circuit D Overvoltage and Undervoltage Protection D Programmable Short-Circuit Protection APPLICATIONS D Notebook PCs, PDAs D Consumer Game Systems D DSP Application DESCRIPTION The TPS5110 provides one PWM-mode synchronous buck regulator controller (SBRC) and one low drop-out (LDO) regulator controller. The TPS5110 supports a low-voltage/high-current power supply for I/O and other peripherals in modern digital systems. The SBRC of the TPS5110 automatically adjusts from PWM mode to SKIP mode to maintain high efficiency under all load conditions. The LDO controller drives an external N-channel power MOSFET that realizes fast response and ultra-low dropout voltage. A unique overshoot protection circuit prevents a voltage hump at fast load decreasing transients. The current protection circuit for SBRC detects the drain-to-source voltage drop across the low-side and high-side power MOSFET while it is conducting. Also, the current protection circuit has a temperature coefficient t...