The Review of DC Motor Drivers——L298N, TB6612FNG and LV8406T


(Here to the conclusion of the review directly.)

I bought a unit of Makeblock starter kit last month and used it to build tank. I have to find the DC motor driver to control my motors since there was no electronic modules in the kit. However, while I was looking for the modules on web, I didn’t find the instruction of how to choose it. As a result, I bought some modules and tried a test to figure out which one is the best. Here is the records of my test.

1. L298N, TB6612FNG and LV8406T

I found three kinds of DC motor driver chips which was the mainstream on the web. Here are the specs of the chips.


2.The Factors of DC Motor Driver Test.

  • Efficiency
  • Security
  • Operating Voltage
  • Operating Current
  • Loading Performance

In addition to the above-mentioned factors, the heat performance, circuit design and the volume of the chip are also the factors which we use to review the modules.

I bought 5 modules for this test---- two L298Ns, two TB6612FNGs and one LV8406T.

The L298N modules, there is a opticalcoupler on the right one.

The TB6612FNG modules. The left one is bought from Sparkfun, the right one is the motor driver from Makeblock.

This is the baseboard which is a combination of motor-driver and Arduino from Makeblock. The driver chip is LV8406T.


3.The Review

1). Efficiency

In order to get the efficiency of the DC motor driver, we need to figure out the power of motors and the power of the whole circuit. Our motor’s nominal voltage is 6V, 155RPM±.

The calculation formula of motor driver is: Pmotor driver=pmotor/ (pmotor driver+ Pmotor). For an instance, while the supply voltage is 9V, the data of L298N is,

According to the data, the voltage drop of L298N is 1.99V.
And the efficiency of L298N under 9V is I1V/ (I2V1) = 59.24%, which was nothing like TB6612FNG and LV8406T (The efficiency of this two modules are 80%-90%, you can find the detailed data in appendix 1. As a result, the rotate speed difference between two modules is 40-50RPM!

As a conclusion, TB6612FNG and LV8406T are better than L298N in efficiency test.

2). Security, Operating Voltage, Operating Current, Heat Performance and the Volume of the Module.

A.Security and Heat Performance

In the aspect of security, L298N has 8 fly-wheel diodes to protect the chip while the back electromotive force which would burn the chip. TB6612FNG from Sparkfun incorporate a protection circuit. And, the Baseboard (LV8406T) from Makeblock has a complete protection design which has capacitance, constant voltage chip, resettable fuse and heat sink. Both of the capacitance and constant voltage are used to prevent device malfunction or breakdown caused by the current resulting from the inrush current at power ON or the negative current resulting from the back electromotive force at power OFF.

The resettable fuse was used to prevent the burning of chip while the motors were locked. The current would increase immediately in this case. Then, the resettable fuse would increase its resistance to cut off the circuit, so that the driver chip was protected. The fuse would reduce its resistance while the motor was released.

The picture below shows that the current would increase to 1.96A while a motor was locked,

The heat performance ranking is L298N< LV8406T <TB6612FNG. The Heat Sink is necessary for L298N and LV8406T, it would dissipate the accumulated heat while the motors were breaking frequently. In this review, I have burn out a LV8406T chip without a heat sink unfortunately.

B.The Volume and the Wiring Complexity Comparison

The TB6612 modules are much smaller than L298Ns.

Particularly, the wiring complexity of Makeblock motor-driver and baseboard are much better than both the Sparkfun TB6612 and L298Ns. Look at the pictures,

Baseboard (LV8406T) wiring

Motor-driver (TB6612FNG) wiring

TB6612 wiring

3). Loading Performance

At the end of the testing, I added the Baseshield from Makeblock as a comparison with baseboard which is a combination of Arduino and Baseshield. Baseshield contains the function of a motor driver with TB6612FNG.

Baseshield, which has to pluged on the Arduino to use

The detailed test data is presented at the appendix 2. Here, the result of the test shows that the loading performance rankings is,

TB6612FNG Sparkfun <Baseshield (TB6612FNG) < Baseboard (LV8406T).

Sparkfun module could drive two DC motors under 12V supply voltage while the PWM is 255. However, when we drive 3 motors, the Arduino would be restart because of the back electromotive force would pull down the supply power of chip, which could cause the reset of Arduino.

While we try to drive 3 motors by TB6612FNG from Sparkfun, they can’t even launch up.

Baseboard is perfect functional while we use it to drive 3 motors

In particular, Baseshield and Baseboard could drive 4 motors under 12V.

It’s very helpful to simplify the wiring when we build a 4WD car or a MDOF robot arm. We can get the transient voltage spike from the OSC picture below. The voltage is 2.8V when we change the direction of motors. It is higher than the protected voltage of the Arduino chip, which is 2.7V.


4. Conclusion

Through this review, we found that TB6612FNG and LV8406T are much better than L298N in all aspects except the price. L298N is cheaper than TB6612FNG. The design of Makeblock baseboard is very unique. It could drive four DC motors simultaneously. In the meantime, the wiring is very simple and concise.

In addition,try not to break or reverse the motors while the PWM is relatively high. And, in order to improve the reliability and security of the circuit, external resettable fuse and capacitance are very helpful.



1.The Full Version of Efficiency Test Data

2. The Data of the Loading Performance Test


The review is so completely!!!


Very nice!
Well done!


how did u capture the spike voltage drop? I tried an oscilloscope but couldn’t catch that