Description

This reference design is a power stage for brushless motors in battery-powered garden and power tools rated up to 1 kW: operating from a 10-cell lithium-ion battery with a voltage range from 36 to 42 V. The design uses 60V: N-channel NexFETsTM featuring a very low drain-to-source resistance (RDS_ON ) of 1.8 mΩ in a SON5x6 SMD package: which results in a very small PCB form factor of 57 × 59 mm. The three-phase gate-driver is used to drive a three-phase MOSFET bridge: which can operate from 6 to 60 V and supports programmable gate current with maximum setting of 2.3-A sink / 1.7-A source. The C2000™ Piccolo™ LaunchPad™ LAUNCHXL-F28027 is used along with this power stage and 120 degree trapezoidal control of BLDC motor with Hall sensors is implemented in software. The cycle by cycle current limit feature in the gate-driver protects the board from excessive current that is caused during motor stalls: by limiting the maximum current allowed in the power stage to a safe level.