LX1675 Datasheet | Microsemi

TM ® Multiple Output Load SHARE™ PWM P RODUCTION D ATA S HEET DESCRIPTION KEY Features - Four Independently Regulated Outputs - Single Input Supply with Wide Voltage Range: 4.5-24V - Outputs As Low As 0.8V Generated From a Precision Internal Reference - Selectable PWM Frequency of 300KHz or 600KHz - Buffered Reference Voltage Output - Multiphase Output Reduces Need for Large Input Capacitance at High Currents - Integrated High Current MOSFET Drivers - Independent Soft-Start and Power Sequencing - Adjustable Linear Regulator Driver Output - No Current-Sense Resistors - DDR Termination pliant - Ro HS pliant for Pb Free APPLICATIONS The LX1675 is a highly integrated power supply controller IC featuring three voltage mode PWM switching ..net regulator stages with an additional onboard linear regulator driver. Two of the constant frequency PWM phases can be easily configured for a single Bi-Phase high current output or operated as two independently regulated outputs. All outputs (PWM phases and LDO) have separate, programmable softstart sequencing. This versatility yields either three or four independently regulated outputs with full power sequencing capability giving system designers the ultimate flexibility in power supply design. Current limit for each PWM regulator is provided by monitoring the voltage drop across the lower MOSFET power stage during conduction, utilizing the Rds(on) impedance. This eliminates the need for expensive current sense resistors. Once current limit has been reached and persist for 4 clock cycles, the output is shut off and Soft Start is initialized to force a hiccup mode for protection. High current MOSFETs can be directly driven to provide an LDO output of 5A and 15A for each PWM controller. This is useful for I/O, memory, termination, and other supplies surrounding today’s micro-processor based designs. The LX1675 accepts a wide range of supply voltage ranging from 4.5V to 24V. Each PWM regulator output...