MCP14628-E/MF Microchip

MCP14628 2A Synchronous Buck Power MOSFET Driver Features General Description Dual Output MOSFET Driver for Synchronous The MCP14628 is a dual MOSFET gate driver Applications designed to optimally drive two N-Channel MOSFETs arranged in a non-isolated synchronous buck converter High Peak Output Current: 2A (typical) topology. With the capability to source 2A peaks Adaptive Cross Conduction Protection typically from both the high-side and low-side drives, Internal Bootstrap Blocking Device the MCP14628 is an ideal companion to buck control- +36V BOOT Pin Maximum Rating lers that lack integrated gate drivers. Additionally, Enhanced Light Load Efficiency Mode greater design flexibility is offered by allowing the gate drivers to be placed close to the power MOSFETs. Low Supply Current: 80 A (typical) High Capacitive Load Drive Capability: The MCP14628 features the capability to sink 3.5A - 3300 pF in 10 ns (typical) peak typically for the low-side gate drive. This allows the MCP14628 the capability of holding off the low-side Tri-State PWM Pin for Power Stage Shutdown power MOSFET during the rising edge of the PHASE Input Voltage Undervoltage Lockout Protection node. Internal adaptive cross conduction protection Space Saving Packages: circuitry is also used to mitigate both external power - 8-Lead SOIC MOSFETs from simultaneously conducting. - 8-Lead 3x3 DFN The low resistance pull-up and pull-down drives allow the MCP14628 to quickly transition a 3300 pF load in Applications typically 10 ns and with a propagation time of typically 20 ns. Bootstrapping for the high-side drive is internally High Efficient Synchronous DC/DC Buck implemented which allows for a reduced system cost Converters and design complexity. High Current Low Output Voltage Synchronous The PWM input to the MCP14628 can be tri-stated to DC/DC Buck Converters force both drive outputs low for true power stage High Input Voltage Synchronous DC/DC Buck shutdown. Light load system efficiency is improved by Converters using the diode emulation feature of the MCP14628. Core Voltage Supplies for Microprocessors When the FCCM pin is grounded, diode emulation mode is entered. In this mode, discontinuous conduc- tion is allowed by sensing when the inductor current reach zero and turning off the low-side power MOSFET. Package Types 8-Lead DFN 8-Lead SOIC 8 1 8 1 HIGHDR PHASE HIGHDR PHASE 7 BOOT 2 7 FCCM BOOT 2 FCCM 3 6 PWM 3 6 V V PWM CC CC 4 5 GND 4 5 LOWDR GND LOWDR Note 1: Exposed pad on the DFN is electrically isolated. 2008 Microchip Technology Inc. DS22083A-page 1MCP14628 Typical Application Schematic C BOOT V = 12V SUPPLY CURRENT SENSE BOOT MCP14628 V = 5V Q CC H V UGATE CC PHASE FCCM FCCM CONTROL Q L PWM LGATE GND VEXT MCP1630 V FB CC CURRENT CS COMP SENSE V OSC IN REF GND REFERENCE VOLTAGE OSCILLATOR FROM MCU Functional Block Diagram V BOOT CC FCCM HIGHDR Level Shift R PHASE PWM Control Logic & Protection R V CC LOWDR GND DS22083A-page 2 2008 Microchip Technology Inc.