Stepper driver – TMC220x

Table of Contents

Overview
Features
Technical Specifications
Pinout
Wiring diagram
Motor Current Setting
Datasheet
Fritzing model
Source

Overview #

TMC2208 is an ultra-quiet two-phase stepper motor drive chip, continuous drive current 1.4A, peak current 2A, voltage range 4.75V-36V, 256 subdivision. The flexible microPlyer interpolation unit provides up to 256 subdivisions, allowing perfect sinusoidal control even in systems with limited pulse frequencies; these are also designed because stealthChop2 ultra-quiet technology is widely used in 3D printing. Compatible with existing 3D printer electronics, eliminating the expensive costs of redesign. With a standard step/dir interface, it is easy to use. It can replace the original TMC2100, lower heat, especially for 3D printing market.

Features #

UART configuration interface (9600-500k Baud)
Power tube built-in drive current 1.4A ,peak current 2A, voltage range 4.75V-36V
Up to 256 native microsteps (without interpolation)
CoolStep ™ current dynamic adjustment technology, can save 70% of the energy
stealthChop2 – faster motor acceleration/deceleration than stealthChop
dcStep ™, stallGuard2 ™ stall detection technology
Automatic stealthChop and spreadCycle switchover depending on velocity
Hardware compatible with StepStick and Pololu A4988 Stepper Driver
Components on bottom PCB side for better heat emission
Automatic standby current reduction
SteaClthhop mute technology
spreadCycle – highly dynamic motor control chopper

Technical Specifications #

Model	TMC2208
Interface	Step/Dir
Configuration	CFG Pins or UART
Native Microsteps	up to 1/256
microPlyer Microsteps	1/256
Logic Voltage (VIO)	3-5V
Motor Voltage (VM)	5.5-36V
Motor Phase Current max	1.2A RMS, 2.0A Peak
Internal V- Regulator	enabled
RDSon	<=0.3 Ohm
stealthChop (quiet)	yes
spreadCycle	yes
coolStep	no
stallGuard	no
dcStep	no

Pinout #

To enable the USART pin you will have to bridge connection under the board like this

Pin	Function
	Power Supply
GND	Ground
VM	Motor Supply Voltage
VIO	Logic Supply Voltage
	Motor Outputs
M1A	Motor Coil 1
M1B	Motor Coil 1
M2A	Motor Coil 2
M2B	Motor Coil 2
	Control Inputs
STEP	Step-Signal Input
DIR	Direction-Signal Input
	TMC2208
EN	Enable Motor Outputs: GND=on, VIO=off
MS1	Step-Configuration
MS2	Step-Configuration
PDN	UART and Auto Power Down Control: GND=on, VIO=off
CLK	Clock Input
DIAG	Diagnostics Output
INDEX	Index Output
VREF	Analog Reference Voltage

Wiring diagram #

The TMC2208 outputs continuous motor current up to 1.4A and peak current up to 2A. Therefore, the reference voltage of the driver module should not exceed 1V. At the same time, the driver module must be dissipated, otherwise it will affect the life of the driver module.

Motor Current Setting #

The best way to set the motor current is by measuring the voltage on the Vref pin (0…2.5V) and adjusting the voltage with the potentiometer. The maximum settable motor current is 1.77A RMS (0.11Ohm sense resistors), but the SilentStepSticks can only be used up to 1.2A RMS.
Irms = (Vref * 1.77A) / 2.5V = Vref * 0.71
Vref = (Irms * 2.5V) / 1.77A = Irms * 1.41 = Imax
Vref -> Voltage on Vref pin
Irms -> RMS (Root Mean Square) current per phase (Irms = Imax / 1.41)
Imax -> Maximum current per phase (Imax = Irms * 1.41)

1. Vref measures Gnd and the voltage at the middle of the potentiometer.
2. Do not connect the motor when measuring the voltage, otherwise it is easy to burn the driver.
3. Power should be connected when measuring voltage, do not just connect USB power supply.
4. Please pay special attention to directions!