98% Efficient, High Power Density Brushless Motor Drive Reference Design" />
TIDUCL0 January 2017
The TIDA-00774 is a 1-kW power stage for a three-phase brushless DC (BLDC) motor in power tools operating from a 5-cell Li-ion battery with a voltage up to 21 V. The design is a 65-mm×60-mm compact drive, implementing sensor-based trapezoidal control. The design takes advantage of TI's MOSFET Power Block technology, which integrates two FETs in half-bridge configuration into a single SON 5×6 package, enabling very high power density. The design uses two power blocks in parallel and delivers 50-ARMS continuous (120-A peak for 3 seconds, 160-A peak for 1 second) winding current. The MOSFET power block with minimum parasitic inductance and the current controlled gate driver with slew rate control helps in effective MOSFET paralleling and reduces switching spikes. The current sensing is done by monitoring MOSFET VDS. The board provides cycle-by-cycle overcurrent and short-circuit protection.