Actuator modules

AXA-001 — TB6612FNG dual DC motor driver PMOD module

Catalog #1 in the AruviX actuator line, level L2. Toshiba TB6612FNG dual H-bridge: two brushed DC motors, PWM + direction per channel, standby gate.

Level L2 ERC clean DRC clean Fab package 10 components

3D render of the AXA-001 PCB — Rendered from the PCB layout. No physical board has been manufactured.

Circuit review & bench-test guide →

Components#

Every placed component, with the reason it is on the board. Extracted directly from the schematic, so this cannot drift from the design.

Ref	Value	What it does on this board	Part number	Footprint
`C1`	10uF 25V X5R	VM bulk reservoir for motor switching current	`GRM21BR61E106KA73L` Murata	`C_0805_2012Metric`
`C2`	10uF 25V X5R	VM bulk reservoir for motor switching current	`GRM21BR61E106KA73L` Murata	`C_0805_2012Metric`
`C3`	100nF 16V X7R	VM high-frequency decoupling at the driver	`GRM188R71C104KA01D` Murata	`C_0603_1608Metric`
`C4`	100nF 16V X7R	VCC logic decoupling	`GRM188R71C104KA01D` Murata	`C_0603_1608Metric`
`J1`	PMOD PLUG 2x6	PMOD peripheral plug (Digilent spec 1.2)	not selected generic	`PinHeader_2x06_P2.54mm_Horizontal`
`J3`	VM IN 2.5-13.5V	Motor supply input: 1 VM (2.5-13.5 V), 2 GND (joins PMOD GND here)	not selected Phoenix Contact	`TerminalBlock_Phoenix_MKDS-1,5-2-5.08_1x02_P5.08mm_Horizontal`
`J4`	MOTOR A	Motor A output: 1 AO1, 2 AO2	not selected Phoenix Contact	`TerminalBlock_Phoenix_MKDS-1,5-2-5.08_1x02_P5.08mm_Horizontal`
`J5`	MOTOR B	Motor B output: 1 BO1, 2 BO2	not selected Phoenix Contact	`TerminalBlock_Phoenix_MKDS-1,5-2-5.08_1x02_P5.08mm_Horizontal`
`R1`	10k	STBY pull-down: both bridges disabled until the host drives STBY high	`RC0603FR-0710KL` Yageo Datasheet ↗	`R_0603_1608Metric`
`U1`	TB6612FNG	Dual DC motor driver H-bridge, 1.2 A per channel, VM 2.5-13.5 V	`TB6612FNG,C,8` Toshiba Datasheet ↗	`SSOP-24_5.3x8.2mm_P0.65mm`

Signals#

Net labels used in the schematic, which are also the names the HDL top level should use.

3V3 AIN1 AIN2 AO1 AO2 BIN1 BIN2 BO1 BO2 GND PWMA PWMB STBY VMOT

Production status#

Schematic ERC	0 violations
PCB layout	complete
DRC	0 violations
Fab package	exported (24 gerbers + drill + CPL + BOM)
Fabricated	no — design stage only

Source: boards/actuator-modules/axa-001-dc-motor

Catalog #1 in the AruviX actuator line (../README.md), level L2. Toshiba TB6612FNG dual H-bridge: two brushed DC motors, PWM + direction per channel, standby gate.

Status: schematic generated, ERC clean (0/0), netlist reviewed. PCB layout not started. Not released.

What it teaches#

PWM motor drive in fabric: the PWMx + xIN1/xIN2 truth table (CW / CCW / short-brake / stop) at up to 100 kHz, standby gating, and motor/logic power separation. Pairs with AXA-003 (encoder interface) for the closed-loop PID lab — the line's signature FPGA-beats-MCU demo.

Design#

TB6612FNG (TB6612FNG,C,8), SSOP-24. 1.2 A per bridge continuous.
Motor power (VM, 2.5–13.5 V) enters on the J3 screw terminal only — never through the PMOD. Stay inside 2.5–13.5 V; the absolute maximum is 15 V. Grounds join on the module (PGND1/PGND2/GND all to the common ground).
VCC (logic) is the PMOD 3V3. Decoupling: 2× 10 µF 25 V 0805 + 100 nF on VM, 100 nF on VCC.
STBY has a 10 kΩ pull-down: both bridges stay safely disabled until the host deliberately drives PMOD pin 9 high.
Motor outputs: AO1/AO2 → J4, BO1/BO2 → J5 (MKDS 1x02 screw terminals).
All PMOD lines are host-driven, so no 100 Ω series resistors (the sensor-line rule applies to module-driven lines only).
Flyback: the H-bridge body diodes are the recirculation path for the motor windings (line flyback rule satisfied internally).
Line-rule exception (documented): the TB6612FNG has no fault or current-sense output, so this module cannot bring a fault signal back to the PMOD. The high-current slot (AXA-002, DRV8871) covers current limiting.

PMOD pin	1	2	3	4	5	6	7	8	9	10	11	12
Net	PWMA	AIN1	AIN2	PWMB	GND	3V3	BIN1	BIN2	STBY	NC	GND	3V3

Regenerate#

python3 generate_design.py

Remaining for release#

[ ] PCB layout (20 × 40 mm actuator outline), DRC, fab outputs
[ ] hdl/: pwm_gen + motor direction controller, testbench, ECP5 demo
[ ] BOM export and availability check, design-review checklist