Triple Monolithic Step-Down Regulator with LDO
DESCRIPTION
The LT®3507 is a triple, current mode, DC/DC converter with internal power switches and a low dropout regulator. The switching converters are step-down converters capable of generating one 2.4A output and two 1.5A outputs. All three converters are synchronized to a single oscillator. The 2.4A output runs with opposite phase to the other two converters, reducing input ripple current. Each regulator has independent shutdown and soft-start circuits, and generates a power good signal when its output is in regulation, easing power supply sequencing and interfacing with microcontrollers and DSPs.
FEATURES
■ Wide Input Range: 4V to 36V
■ One 2.4A and Two 1.5A Output Switching Regulators with Internal Power Switches
■ Low Dropout Linear Regulator with External Transistor
■ Antiphase Switching Reduces Ripple
■ Independent Run, Tracking/Soft-Start, and Power Good Indicators Ease Supply Sequencing
■ Uses Small Inductors and Ceramic Capacitors
■ Adjustable, 250kHz to 2.5MHz Switching Frequency, Synchronizable Over the Full Range
■ User Programmable Overvoltage and Undervoltage Lockouts
■ Thermally Enhanced, 38-Lead 5mm × 7mm QFN Package
APPLICATIONS
■ DSL and Cable Modems
■ Distributed Power Regulation
■ DSP Power
■ Automotive