Lianna Dicke MOTOR HARDWARE BREAKDOWN. Design Goals: Drive DC motor that draws 5 A maximum...

Lianna Dicke

MOTOR HARDWAREBREAKDOWN

Design Goals:• Drive DC motor that draws 5 A maximum continuous current• Voltage operation at 12 Volts (automotive)• Low cost• Possibility of being driven in both directions• Commands will come from Teensy 3.1 controller• Commands will include PWM and direction control

Due to a major design scope change (new actuator), a detailed schematic is not included in this documentation

DRV8701: Gate Driver

Teensy 3.1

CommandsH-BRIDGE MOTOR

POSITION SENSOR

High Level Block Diagram

This is a high level diagram of the functionality of the motor driver hardware(Provided by Texas Instruments)

H-Bridge to Motor Connections: connected to four NMOS power transistors, which are capable to handle 5A

Reverse Supply Protection: if hooked up backwards, there will not be any current going through the H-Bridge

DRV8701

Speed Sensor: indicates how much current is going through

H-Bridge Directional Flow

Texas Instrument Gate Driver Chip: DRV8701The internals of the chip

Inputs from Teensy 3.1

Outputs for Teensy 3.1: Open Collector

H-Bridge to Motor Connections:Power Stage

Power Generation: Control Logic Power

Differential Amplifier: reads out a voltage due to Rsense and feedbacks to Outputs and Logic that controls the Gates

Layout Design Goal (Provided by TI)

Land Pattern Data : (Footprint)

Recommendation from TI:Add thermal pad under IC; add vias to distribute thermal energy

Hardware Implementation: Prototype

https://www.pololu.com/picture/view/0J6859