Connecting the controller
Integrating the CPB in a motherboard
The minimum wiring varies depending on motor type and any present feedback (stepper or BLDC motor, Hall sensors/encoders). For commissioning, the connection of the voltage supply (X1 — voltage supply and motor) of the motor and of an RS485 transceiver is sufficient.
The following table shows the necessary voltage rails and the requirements that your motherboard should satisfy for them. When calculating the current consumption, a low efficiency of 80% is assumed for the step-down converter.
Voltage rail | Used for | Current consumption | Ripple permitted | Tolerance of the regulated voltage | Recommended topology |
---|---|---|---|---|---|
+10-12V | Gate-Drivers, +3.3V, +5V | 70…160 mA | 100 mV p-p | Step-down converter for main supply UB | |
+5V | Encoder/ Hall, +3.3V | 150 mA max. | 100 mV p-p | Step-down converter for +10-12V | |
+3.3V | MCU | 140 mA min. | +/-3% | Low-dropout regulator (LDO) |
Connecting switches for communication settings
You can connect two rotary switches to the specified pins of the controller that you can then use to set the communication parameters. The wiring must correspond exactly to the reference circuit given below. The three pins intended for this purpose are pin 28 (MISO), pin 30 (SCK) and pin 33 (SH/LD).

- Use shift register 74HC165D or an equivalent product. Connect pin 10 to the 3.3 volt supply via a pull-up resistor so that the controller can detect the circuit.
- If you do not wish to use any rotary switches, do not connect anything to the three specified pins: MISO (pin 28), SCK (pin 30) and SH/LD (Pin 33).
For the controller to detect and use the rotary switches, you must write the value "1" in object 2104h:01h (this is the case in the factory settings). If the value of the object is "0", the stored values in the corresponding objects are used. You can find the objects and the possible combinations in chapter Configuring via Modbus RTU.