3946 Datasheet (Allegro Micro Systems) - Half-bridge Power MOSFET Controller

3946, Half-bridge Power MOSFET Controller

VREG.

A 13 V output from the on-chip charge pump, used to power the low-side gate drive circuit directly, provides the current to charge the bootstrap capacitors for the high-side gate drive.

The VREG capacitor, CREG, must supply the instantaneous current to the gate of the low-side MOSFET.

A 10 µF,

3946 Half-Bridge Power MOSFET Controller A3946KLB SOIC Data Sheet 29319.150 VREG CP2 CP1 PGND GL S 1 2 3 4 5 6 7 8 16 VBB 15 VREF 14 DT 13 LGND 12 RESET 11 IN2 The A3946 is designed speciﬁcally for applications that require high power unidirectional dc motors, three-phase brushless dc motors, or other inductive loads.

The A3946 provides two high-current gate drive outputs that are capable of driving a wide range of power N-channel MOSFETs.

The high-side gate driver switches an N-channel MOS

3946 Features

* On-chip charge pump for 7 V minimum input supply voltage High-current gate drive for driving a wide range of N-channel MOSFETs Bootstrapped gate drive with charge pump for 100% duty cycle Overtemperature protection Undervoltage protection