The MCP14628 is a dual MOSFET gate driver
designed to optimally drive two N-Channel MOSFETs
arranged in a non-isolated synchronous buck converter
topology. With the capability to source 2A peaks
typically from both the high-side and low-side drives,
the MCP14628 is an ideal companion to buck controllers
that lack integrated gate drivers. Additionally,
greater design flexibility is offered by allowing the gate
drivers to be placed close to the power MOSFETs.
The MCP14628 features the capability to sink 3.5A
peak typically for the low-side gate drive. This allows
the MCP14628 the capability of holding off the low-side
power MOSFET during the rising edge of the PHASE
node. Internal adaptive cross conduction protection
circuitry is also used to mitigate both external power
MOSFETs from simultaneously conducting.
The low resistance pull-up and pull-down drives allow
the MCP14628 to quickly transition a 3300 pF load in
typically 10 ns and with a propagation time of typically
20 ns. Bootstrapping for the high-side drive is internally
implemented which allows for a reduced system cost
and design complexity.
The PWM input to the MCP14628 can be tri-stated to
force both drive outputs low for true power stage
shutdown. Light load system efficiency is improved by
using the diode emulation feature of the MCP14628.
When the FCCM pin is grounded, diode emulation
mode is entered. In this mode, discontinuous conduction
is allowed by sensing when the inductor current
reach zero and turning off the low-side power
MOSFET