- 36-V/1-kW, 99% Efficient, 18-cm2 Power Stage Ref Design for 3-Phase BLDC Motors
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30 Aug 2017 1,001 views
This 1kW power stage reference design achieves 99% efficiency for a three-phase, 36V brushless DC (BLDC) motor used in industrial applications such as power tools that operate from a 10-cell Li-ion battery. The design demonstrates the smallest inverter power stage for this power levels, implementing sensorbased trapezoidal control and supports 25ARMS continuous (60A peak for 2 seconds, 100A peak for 400 milliseconds) winding current. The design’s MOSFET power block and current controlled gate driver helps clean MOSFET switching and lowest EMI due to slew rate control and low parasitic inductance.
- Operates at voltage ranging from 6V to 42V (10s li-ion battery) delivering 25ARMS continuous (60A peak for 2s, 100A peak for 400ms, 400A for 10ms) motor winding current
- 36V/700W, 18ARMS support without heat sink in a small 50mm x 36mm PCB form factor
- MOSFET current monitoring and overcurrent protection by VDS sensing with response time less than 1µs