Using the Sparkfun Motor Driver 1A Dual TB6612FNG using Arduino

As a beginner myself, I struggled to find a one-stop set of instructions to get up and running with Sparkfun’s Motor Driver 1A Dual TB6612FNG.  This motor driver breakout board is exceptional value, is beautifully small, but does need a little more effort to get it working.

The TB6612FNG is an H-Bridge driver – I won’t go into the technicalities of how it works, but the end result is that it can turn a connected motor in either direction and at a variable speed.  This allows you to build a very agile robot driven by 2 motors that can:
– move forward
– move backward
– turn in a very tight circle by driving one motor forward and one motor in reverse
– a variety of other moves using differential motor speeds and directions

To keep this instructable focused on the driver, I’ve built the bot on a simple Meccano body and haven’t extended it to include any obstacle detection – the bot just drives a set pattern.

Before you start – the driver’s specs:
– Logic supply voltage (VCC) of 2.7-5.5 VDC
– Motor supply voltage (VM) up tp 15VDC
– Current of 1.2A constant per channel (3.2A peak)
– Drives up to 2 motors

Images:
1. Finished Robot
2. The TB6612FNG breakout board
3. Full circuit diagram

Step 1: Get your stuff

First: The Ingredients
– 1 x Sparkfun Motor Driver 1A Dual TB6612FNG
– 1 x set of Header pins
– 1 x Breadboard plus connecting wires
– 8 x 1N4001 rectifier diodes (or similar)
– 1 x Arduino Uno R3
– 1 x 6V power supply (I used 4x 1.2V NiMH rechargeables in a holder)
– 1 x 9V battery with a 2.1mm barrel connector
– 2 x DC motors not exceeding the driver’s current and voltage rating (I used Pololu’s 250:1 micro metal gearmotor for their manageable RPM and high torque)
– Mounting brackets and wheels (I used Pololu’s extended gearmotor brackets and 32×7 wheels – small wheels = manageable speed)
– Something to build the body (Meccano, Lego, thick corrugated card, etc)

Second: The Cooking Utensils
– Soldering Iron
– Resin core solder
– Wire strippers

Step 2: Solder Your Connections

You’ll need to solder a few connections before you get started.  I found the fine solder work to be daunting, but randofo’s How-To helped immensely – along with a good dose of practice on some old boards I found lying around.

The breakout board
The TB6612FNG breakout comes without pins – so you’ll need to solder your own.

Snap 2 sets of 8 header pins off the strip using pliers to get a clean break on the right pin.  Place the header pins into a breadboard, and then the breakout board on top of this – this will ensure the right spacing and a 90 degree angle between the board and the header pins.  I’ve also used play-doh to hold pins in place (play-doh won’t melt, it simply goes crisp and can be picked off).  You’ll see from my less-than-fine solder work that I’m still getting to grips with my soldering iron!

Battery connections – the Motor’s battery
The motor will run off a separate 6V source.  Depending on the type of connector you have for your battery holder, you may need to solder header pins onto the leads – the power for the motor will connect into the breadboard. (The breakout board has capacitors on-board to isolate noise from the motor, so no need to add these yourself)

Battery connections – the Arduino battery
The Arduino will run off a 9V battery, so that it doesn’t need to be tethered to the USB cable.  Depending on the connector/holder you have you may need to solder a 2.1mm barrel connector onto the leads (make sure the centre pin is soldered to the positive lead).  Alternatively buy a holder with a connector already attached.

Motor Terminals
Finally, solder wires to the motors’ terminals. I used jumper wires, stripped the one end and soldered it onto the motor. That way, you have the pins to connect the motor to the breadboard.

Images:
1. Soldering the breakout board (can you tell I’m still learning!?!)
2. Battery connectors soldered
3. Motor terminals soldered and motors mounted

Step 3: Set Your Breadboard Up