Figure 3-4. ATSAMD21BLDC24V-STK Block Diagram
3.2.1.
Half-bridge FET Driver
The half-bridge circuit is based on the NTMFS5C646NL N-channel Power MOSFET. Each half-bridge is
driven by the NCP5106A gate driver. The gate driver takes two independent PWM inputs from the MCU
and uses bootstrap technique to drive the high side Power MOSFET in the half-bridge. The bootstrap
capacitor is tied between PIN5 and PIN8 of the NCP5106 through a resistor. C5 is the bootstrap capacitor
and D1 is the bootstrap diode for phase-U half-bridge, as shown in the figure below. The bootstrap
capacitor value is chosen based on the total charge to be supplied by the capacitor and maximum
allowable voltage drop on the bootstrap capacitor.
Atmel ATSAMD21BLDC24V-STK [USER GUIDE]
Atmel-42681A-SMART-ARM-based-Motor-Control-Kit_User Guide-02/2016
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