13 MOSFET Gate Driver Module

The MOSFET Gate Driver module (MOSFET Driver module) incorporates a number of functions, that when paired with the host dsPIC® DSC, provides a single chip solution for controlling low-voltage motors. The MOSFET Driver module includes:

  • Bias Generator:

    - +12V Low-Dropout (LDO) Linear Regulator

    • Charge Pump

    - +3.3V @ 70 mA LDO can be used to power the Host dsPIC DSC

    • Input supply and temperature supervisor
  • Motor Control Unit:
    • External drive for a three-phase bridge with NMOS/NMOS MOSFET pairs
  • Communication Port:
    • Half-duplex UART with internal connection to the Host dsPIC DSC

Figure 13-1 depicts the functional block diagram of the MOSFET Driver module and Figure 13-2 depicts a typical application circuit.

Figure 13-1. Functional Block Diagram – MOSFET Gate Driver Module
Note:
  1. Device interconnect is connected directly to the Host microcontroller within the dsPIC33CDVL256MC506 device package.
Figure 13-2. MOSFET Gate Driver Module – Typical Motor Control Application Circuit
Note:
  1. Internal pull-up resistors for RC12 and RD1 must be enabled by the user by setting the corresponding bits in the CNPUC and CNPUD registers, respectively.
  2. The ADC can be configured to internally sample Op Amp outputs.
  3. A Schottky diode between the CAP1 pin and HVSS is recommended to ensure that the CAP1 pin absolute minimum voltage specification of -0.3V is maintained.