Motor Driver Board
Datasheet, Design on Altium Drive
| Designer | Cas Doornkamp |
| Last Version | v4.2 |
| Last Updated | 2020 |
Design
General Description
There are four motordriver boards that drive the four motors of the wheels of one robot. This means that for 16 robots we need 60 motordriver PCB’s. The motordriver board controls the speed of a motor. The motor drivers receive a 25KHz PWM signal. A 100% dutycycle indicates no movement, and a 0% dutycycle indicates full power. A second signal is used to indicate the direction of rotation. A third signal indicates if the brakes should be applied. Each of our four drivers control a 50 Watt Maxon motor at 24 Volts, see the Datasheets.
Pmotor 484-1912
Pmotor is the white motor connector and connects to the motor with a 22 AWG cable. To be more specific: it’s the Molex Male Crimp Connector Housing, 4.2mm Pitch, 8 Way, 2 Row. We could prefer smaller connectors, however the motors have these connectors. If we order new motors someday, please take the connectors into account. When the motor driver disconnects from the Top Board, the processor shorts. This is why we use elastic bands to keep them attached (this works but is not ideal obviously).
Pin Phoenix 1814812
Pin (P_in) is the gray side connector of the motordriverboard that connects to the topboard with a cable coming from either P800, P801, P802 or P803 (depending on which motor is being controlled).
U1 ROHM BD63002AMUV
This is a pre-driver of a 3-phase brushless motor. It generates a driving signal from the Hall sensor and drives PWM through the input control signal. Power MOSFETS (Q1…Q6) are used to create a booster circuit.
Pin description of important pins:
Pin 1: FG, FG output.
Pin 2: PWMB, PWM input (negative logic): this drives the speed of the motor and connects to the PWM pinout of Pin connector
Pin 3: CW Changing Direction of rotation. This signal goes to the DIR pinout of the Pin connector.
C_CP, C_REG, Cout1, Cout2, Cout3, Csup2, C_VG
Just the same capacitors of 100nF (0.1uF).
Csup1 (Cap Pol1)
47uF capacitor.
Cin1, Cin2, Cin3
10nF capacitors
C_F
1.8nF capacitor
Q1, Q2, Q3, Q4, Q5, Q6 PSMN1R6-30MLHX
Power mosfets. These mosfets are able to handle the power because of their low resistance (1.9mOhm).
R_F Res1
1.6 kOhm Resistor.
Rdiv1, Rdiv2 CR0603-FX-1003ELF
100kOhm Resistor.
R_sense WSL2512R0600FEA
0.06 Ohm resistor.
BOM file to find values of capacitors, resistors, etc: https://drive.google.com/drive/u/3/folders/1vjxNbx_dwdUcWXVtJE1wquDKGVZyCp89
Components
Testing
-- Testing code