-
Notifications
You must be signed in to change notification settings - Fork 46
Connections
The TMC4671 driver is needed to drive motors like steppers and servos.
Generally the digital TMC pins are only 3.3V tolerant while the analog part is 5V capable.
The STM works at 3.3V logic level with 5V tolerant inputs (unprotected).
Maximum voltage of TMC driver: 60V (48V recommended).
Current rating: Designed for 20A for linear response. (25A peak). You can increase this with different shunts (1mOhm instead of 1.5mOhm).
ALWAYS CONNECT THE BRAKING RESISTOR BETWEEN PB+ AND PB-!
A big servo can generate >100V in milliseconds while braking which will destroy your board and peripherals if not dissipated!
The STM board is made to be stacked on top of the TMC driver and mechanically secured and grounded together with metal standoffs of better noise performance. You can also use a ribbon cable to connect multiple boards but make sure its not too long and still all properly grounded.
On the lower side of the TMC driver are 3 SPI jumpers to select the chip select pins on the connector. In parallel connection the voltage sense dividers and braking resistor enable pins are connected in parallel! This means you must also connect the PB+ (Internal motor voltage) together and NOT use separate supplies!
It is recommended to connect USB before starting the motor power supply to have the gate voltage applied and the driver set up before that.
If the TMC board is used connect it to the TMC ENC port (5V tolerant. 5V pullups and filters with Schmitt-Trigger buffer). If you use only the USB interface (STM Board) connect it to the usb interface instead (5V tolerant. 5V pullups on inputs).
Warning: The analog inputs are not protected and are maximum 5V tolerant. SinCos encoders are analog encoders often used with differential lines. Connect the positive Sine signal to the analog encoder port (WY-P) and the Cosine signal to UX-P.The negative lines to the N pin above the positive pin. If the encoder is single ended connect a jumper in the spot of the negative common mode jumper header behind the AENC header to connect the N line to 2.5V.