Pinout and Powering

Further information about the pin functions and power supply. Note, the component side of the PCB is the bottom.

Pin Functions

PinFunction
Power Supply
GNDGround
VMMotor Supply Voltage
VIOLogic Supply Voltage
Motor Outputs
M1AMotor Coil 1
M1BMotor Coil 1
M2AMotor Coil 2
M2BMotor Coil 2
Control Inputs
STEPStep-Signal Input
DIRDirection-Signal Input
ENEnable Motor Outputs: GND=on, VIO=off, TMC21x0: OPEN=Auto-Power-Down
TMC2100
CFG0Chopper Off Time TOFF: GND=140tclk, VIO=236tclk, OPEN=332tclk
CFG1Step-Configuration
CFG2Step-Configuration
CFG3Current Setting: GND=int, VIO=int, OPEN=ext
CFG4Chopper Hysteresis HEND: GND=5, VIO=9, OPEN=13
CFG5Chopper Blank Time TBL: GND=16, VIO=24, OPEN=36
DIAG0Diagnostics Output 0
DIAG1Diagnostics Output 1
VREFAnalog Reference Voltage
TMC2130 (SPI_MODE=1)
SDO/CFG0Serial Data Output (SPI)
SDI/CFG1Serial Data Input (SPI)
SCK/CFG2Serial Clock Input (SPI)
CS/CFG3Chip Select Input (SPI)
DCEN/CFG4dcStep Enable Input (GND=off)
DCIN/CFG5dcStep Gating Input
DIAG0Diagnostics Output 0
DIAG1Diagnostics Output 1
TMC2208
MS1Step-Configuration
MS2Step-Configuration
PDNUART and Auto Power Down Control: GND=on, VIO=off
CLKClock Input: GND=int. clock
DIAGDiagnostics Output
INDEXIndex Output
VREFAnalog Reference Voltage

TMC2100 Step-Configuration

CFG2CFG1StepsInterpolationMode
GNDGND1-spreadCycle
GNDVIO12-spreadCycle
GNDOPEN121256spreadCycle
VIOGND14-spreadCycle
VIOOPEN141256spreadCycle
OPENVIO141256stealthChop
VIOVIO116-spreadCycle
OPENGND1161256spreadCycle
OPENOPEN1161256stealthChop

TMC2208 Step-Configuration

MS2MS1StepsInterpolationMode
GNDGND181256stealthChop2
GNDVIO121256stealthChop2
VIOGND141256stealthChop2
VIOVIO1161256stealthChop2

Other modes and options can be set via UART (see TMC2208 Configurator).

Powering

The motor supply voltage VM is a strong power supply with a high voltage. Always ensure that there cannot occur voltage spikes on power up. Further Information: Pololu - Understanding Destructive LC Voltage Spikes.

A 100uF capacitor (low ESR) near every SilentStepStick driver is recommended for best performance and for supply voltages >24V a suppressor diode (TVS diode) for over-voltage protection.

Only after the logic supply voltage VIO is present and stable, the driver inputs (STEP, DIR, EN, CFG…) can be driven with a high level.

If the motor is running/moving, then it is not allowed to switch off the power supply. Always make sure that the motor stands still and the motor outputs are deativated on shutting down, otherwise the driver IC can get damaged (because of back EMF). An emergency stop can be realized, when the EN pin is set to VIO (high). This will switch off all motor output drivers and will put the motor into freewheeling.

SilentStepSticks with variable 3-5V logic voltage

At power-up the motor supply voltage VM should come up first and then the logic supply voltage VIO. On power-down the logic supply voltage VIO should turned off at first and then the motor supply voltage VM, because the internal logic of the TMC2xxx driver is powered from VM. To ensure the correct powering a schottky diode from VIO (anode) to VM (cathode) can be added. The v2 Protectors for SilentStepSticks include this schottky diode.

SilentStepSticks with 5V logic voltage

There is no special power-up or power-down sequence needed. If the SilentStepStick is only powered with 5V (logic) then a current can flow backwards to VM. In this case it is not allowed to enable the driver (motor outputs) and no loads (e.g. fans) should be on VM (<=4V), because the current will be drawn from the logic supply VIO.