LTC3612 Datasheet | Linear Technology

Features n 3A Output Current n 2.25V to 5.5V Input Voltage Range n Low Output Ripple Burst Mode® Operation: IQ = 70µA n ±1% Output Voltage Accuracy n Output Voltage Down to 0.6V n High Efficiency: Up to 95% n Low Dropout Operation: 100% Duty Cycle n Shutdown Current: ≤1µA n Adjustable Switching Frequency: Up to 4MHz n Optional Active Voltage Positioning (AVP) with Internal pensation n Selectable Pulse-Skipping/Forced Continuous/ Burst Mode Operation with Adjustable Burst Clamp n Programmable Soft-Start n Inputs for Start-Up Tracking or External Reference n DDR Memory Mode, IOUT = ±1.5A n Available in Thermally Enhanced 20-Pin (3mm × 4mm) QFN and TSSOP Packages Applications n Point-of-Load Supplies n Distributed Power Supplies n Portable puter Systems n DDR Memory Termination n Handheld Devices 3A, 4MHz Monolithic Synchronous Step-Down DC/DC Converter Description The LTC®3612 is a low quiescent current monolithic synchronous buck regulator using a current mode, constant frequency architecture. The no-load DC supply current in sleep mode is only 70µA while maintaining the output voltage (Burst Mode operation) at no load, dropping to zero current in shutdown. The 2.25V to 5.5V input supply voltage range makes the LTC3612 ideally suited for single Li-Ion as well as fixed low voltage input applications. 100% duty cycle capability provides low dropout operation, extending the operating time in battery-powered systems. The operating frequency is externally programmable up to 4MHz, allowing the use of small surface mount inductors. For switching noise-sensitive applications, the LTC3612 can be synchronized to an external clock at up to 4MHz. Forced continuous mode operation in the LTC3612 reduces noise and RF interference. Adjustable pensation allows the transient response to be optimized over a wide range of loads and output capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external catch diode, saving external ponents and...