LT3501 Datasheet | Linear Technology

Features n Wide Input Range: 3.1V to 25V n Two Switching Regulators with 3A Output Capability n Independent Supply to Each Regulator n Adjustable/Synchronizable Fixed Frequency Operation from 250k Hz to 1.5MHz n Antiphase Switching n Outputs Can be Paralleled n Independent, Sequential, Ratiometric or Absolute Tracking Between Outputs n Independent Soft-Start and Power Good Pins n Enhanced Short-Circuit Protection n Low Dropout: 95% Maximum Duty Cycle n Low Shutdown Current: <10µA n 20-Lead TSSOP Package with Exposed Leadframe Applications n DSP Power Supplies n Disc Drives n DSL/Cable Modems n Wall Transformer Regulation n Distributed Power Regulation L, LT, LTC, LTM, Linear Technology, Burst Mode and the Linear logo are registered trademarks and Thin SOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Monolithic Dual Tracking 3A Step-Down Switching Regulator Description The LT®3501 is a dual-current mode PWM step-down DC/DC converter with two internal 3.5A switches. Independent input voltage, feedback, soft-start and power good pins for each channel simplify plex power supply tracking/sequencing requirements. Both converters are synchronized to either a mon external clock input or a resistor programmable fixed 250k Hz to 1.5MHz internal oscillator. At all frequencies, a 180° phase relationship between channels is maintained, reducing voltage ripple and ponent size. Programmable frequency allows for optimization between efficiency and external ponent size. Minimum input-to-output voltage ratios are improved by allowing the switch to stay on through multiple clock cycles, only switching off when the boost capacitor needs recharging, resulting in ~95% maximum duty cycle. Each output can be independently disabled using its own soft-start pin, or by using the SHDN pin the entire part can be placed in a low quiescent current shutdown mode. The LT3501 is available in a 20-lead TSSOP...