Drives a bipolar stepper motor quietly and precisely, with the StealthChop2 chopper that makes the motor nearly silent and up to 1/256 microstepping for smooth motion. A simple STEP/DIR interface moves it, while a single-wire UART configures current, microstep, and modes at runtime, and StallGuard4 senses load to home without a limit switch. It carries up to 2 A RMS from a 4.75 to 29 V supply with integrated MOSFETs. The standard quiet driver for 3D printers and desktop CNC.

Pinout

Pin	Name	Type	Function
1	OB2	output	Motor coil B output 2 (integrated H-bridge output).
2	ENN	input	Enable-not input. Driving this pin high switches the power stage off (all motor outputs floating).
3	GND	power_in	Ground. Connect to GND plane near the pin.
4	CPO	passive	Charge-pump capacitor output. Tie to CPI through a 22nF 50V capacitor.
5	CPI	passive	Charge-pump capacitor input. Tie to CPO using a 22nF 50V capacitor.
6	VCP	passive	Charge-pump voltage. Tie to VS via a 100nF capacitor to bias the high-side gate drivers.
7	SPREAD	input	Chopper mode selection input (internal pull-down): Low = StealthChop, High = SpreadCycle. May be left unconnected.
8	5VOUT	power_out	Output of internal 5V regulator. Bypass with 2.2µF-4.7µF ceramic capacitor to GND near the pin, with the shortest possible loop to the GND pad.
9	MS1_AD0	input	Microstep resolution configuration bit MS1 (internal pull-down). In UART mode selects UART slave address bit 0 (AD0). Combined MS2,MS1: 00=1/8, 01=1/32, 10=1/64, 11=1/16.
10	MS2_AD1	input	Microstep resolution configuration bit MS2 (internal pull-down). In UART mode selects UART slave address bit 1 (AD1).
11	DIAG	output	Diagnostic and StallGuard output. Driven high on stall detection or driver error; error condition is cleared by ENN=high.
12	INDEX	output	Configurable index output; provides an index pulse (one pulse per electrical revolution or overtemperature prewarning).
13	CLK	input	Clock input. Tie to GND with a short wire to use the internal oscillator, or supply an external clock.
14	PDN_UART	bidirectional	Power-down control input (low = automatic standstill current reduction). Doubles as single-wire UART I/O; the power-down function can be disabled in UART mode.
15	VCC_IO	power_in	3.3V to 5V I/O supply for all digital pins (does not power the IC logic core).
16	STEP	input	STEP input; each rising edge advances the motor by one microstep.
17	VREF	input	Analog reference voltage for motor current scaling, or reference current for internal sense resistor mode.
18	GND	power_in	Ground. Connect to GND plane near the pin.
19	DIR	input	Direction input (internal pull-down). Selects motor rotation direction.
20	STDBY	input	Standby input (100kΩ internal pull-down). Pull high to disable the internal supply regulator and place the driver in a low-power state. May be left unconnected. Also drop VREF and pull ENN low during standby.
21	OA2	output	Motor coil A output 2 (integrated H-bridge output).
22	VS	power_in	Motor supply voltage (4.75-29V). Provide filter capacitance near the pin with the shortest possible loop to the GND pad.
23	BRA	passive	Sense-resistor connection for coil A. Place the sense resistor to GND near the pin, or tie to GND when using the internal sense resistor mode.
24	OA1	output	Motor coil A output 1 (integrated H-bridge output).
25	NC	unconnected	Not internally connected. May be tied to GND for improved PCB routing.
26	OB1	output	Motor coil B output 1 (integrated H-bridge output).
27	BRB	passive	Sense-resistor connection for coil B. Place the sense resistor to GND near the pin, or tie to GND when using the internal sense resistor mode.
28	VS	power_in	Motor supply voltage (4.75-29V). Provide filter capacitance near the pin with the shortest possible loop to the GND pad.
PAD	GND	power_in	Exposed die pad. Connect to a GND plane through as many thermal vias as possible; serves as the GND return for the power drivers and analog circuitry.

Key specifications

Parameter	Value
Type	Bipolar stepper motor driver
Supply	4.75-29 V
Current	2 A RMS (2.8 A peak)
Microstepping	Up to 1/256
Interface	STEP/DIR + single-wire UART
Features	StealthChop2, SpreadCycle, StallGuard4 (sensorless homing)
Package	QFN-28 (5x5 mm)

Ordering variants

Same part, different packaging or reel option.

TMC2209-LA-T (QFN-28, tape & reel)

CAD (KiCad official)

Symbol: Driver_Motor:TMC2209-LA (KiCad official)
Footprint: Package_DFN_QFN:VQFN-28-1EP_5x5mm_P0.5mm_EP3.7x3.7mm_ThermalVias
3D model: QFN-28 (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Analog Devices (Trinamic) datasheet (86 pp, sha256 1d9e8eed9ad2edc1, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF