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Miniature Motor Driver Resource

What Are Linear Resonance Actuators?

Welcome to our Motor Driver Resource section. Here we have suggested some chips that are suitable for driving our motors and linear resonant actuators. Please note this is a simple guide and you should always refer to the product’s datasheet for accurate ratings and design advice.

Whilst most DC motors are essentially driven by the same principle (by applying a DC voltage), these chips boast a host of different features. Some accept analogue inputs, others PWM or I2C, H-bridges will enable you to easily change the direction of rotation and haptic drivers are specially designed for haptic feedback applications. We’ve split our guide into the following categories:

• Transistors
• H-Bridges
• Vibration Motor Drivers
• Haptic Feedback Drivers
• Brushless Motor Drivers

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Transistors

Transistors act like an electrical switch, enabling a low current or low voltage source (like a microcontroller) to drive a motor. By closing the switch the transistor can connect the motor to a suitable power supply where it has access to sufficient voltage and current. They can also be used with PWM signals to vary the level of voltage.

There are different types of transistor, here we suggest two MOSFETs; one n-channel (switch closed with high voltage at the base) and on p-channel (switch closed with low voltage at the base). Thousands of different devices exist, far too many to list here. We have previously used the ones below in-house.

Manufacturer	Product Code	Type	Output Range	Link
ON Semiconductor	MGSF1N02L	n-channel	20 V, 750 mA	ON Semiconductor Website
ON Semiconductor	NTR4101	p-channel	20 V, 3.2 A	ON Semiconductor Website

H-Bridges

Built using 4 transistors, H-bridges enable you to easily reverse the polarity of the applied voltage to change the rotation direction. This makes them great for gearmotor applications, or anything where you might want need to rotate the motor both ways.

You can either build it yourself using the MOSFETs above with a reference circuit or purchase a single discrete chip.

There are many different types of design, including ‘half bridges’ and ‘dual H-bridges’. The chips below are all full H-bridges and a couple are ‘dual’ (can drive two motors). Again, there are many more available.

Manufacturer	Product Code	Type	Output Range	Link
STMicroelectronics	L298	Dual Full Bridge Driver	46 V, 4 A	STMicroelectronics Website
STMicroelectronics	L6201	DMOS Full Bridge Driver	60 V, 5A	STMicroelectronics Website
Texas Instruments	DRV8837 ( / 38 / 39)	Full Bridge Driver	11 V, 1.8 A	TI Website
Texas Instruments	DRV8832 ( / 30 / 33)	Full Bridge Driver	6.8 V, 1 A	TI Website
Texas Instruments	DRV8800	Full Bridge Driver	36 V, 2.8 A	TI Website
Freescale	MC33886	Full Bridge Driver	40 V, 5.2 A	Freescale Website
Allegro MicroSystems	A3908	Full Bridge Driver	5.5 V, 500 mA	Allegro Website
Allegro MicroSystems	A4973	Full Bridge Driver	50 V, 1.5 A	Allegro Website

Vibration Motor Driver IC

There is a small selection of components that are specifically designed to operate vibration motors with a simple on/off drive pattern. They operate in a similar method to the transistor chips above, but provide a different output voltage to the supply voltage – much like low-dropout voltage regulator (worth researching).

When using batteries, the supply voltage will vary depending upon the battery’s level of charge – when using a transistor this results in a varying performance from the vibration motor. These ICs will enable you to achieve consistent vibration motor performance across the entire battery range.

Some are fixed and some are adjustable, but most can be controlled by PWM to vary the speed.

These can, of course, be used to drive normal DC and gearmotors too as they output a DC voltage, however, some of them are specifically branded for the vibration motor market. Some users will get better performance from the H-bridges listed above or Haptic Feedback Chips, so be sure to check these other lists.

Manufacturer	Product Code	Type	Output Range	Link
ON Semiconductor	NCP5426	TSOP-5	2 V, 150 mA	ON Semiconductor Website
Maxim	MAX1749	SOT23	6.5 V, 120 mA	Maxim Website

Haptic Feedback Chips

These are the most complex chips in this section. Many of them are able to drive both eccentric rotating mass vibration motors and linear resonant actuators, have a variety of drive methods, include a range of impressive additional features and some even store haptic waveforms – all on a single component.

For top-end haptic feedback performance, you will need one of these devices along with a high-performance haptic actuator.

Manufacturer	Product Code	Type	Output Range	Link
Texas Instruments	DRV8601	ERM / LRA	5.5 V, 400 mA	TI Website
Texas Instruments	DRV2603	ERM / LRA	5.5 V	TI Website
Texas Instruments	DRV2604L	ERM / LRA	5.5 V	TI Website
Texas Instruments	DRV2605	ERM / LRA	5.5 V	TI Website
Fairchild Semiconductor	FAH4820	ERM	3.6 V, 500 mA	Fairchild Website
Fairchild Semiconductor	FAH4830	ERM	3 V, 500 mA	Fairchild Website
Fairchild Semiconductor	FAH4840	LRA	2 V, 200 mA	Fairchild Website

Brushless Motor Driver

Our brushless motors (vibration and normal) are more difficult to drive compared to the brushed DC varieties above. They are electrically commutated, which means the driver activates the different internal coils depending upon the position of the motor to maintain a constant direction of rotation. Of course, the benefit is a greatly improved lifetime as the precious metal brushes (which wear out) are removed.

All of the chips below are sensorless brushless vibration motor drivers and may require some external components, typically 3 resistors between the driver outputs and motor terminals.

Manufacturer	Product Code	Type	Output Range	Link
Texas Instruments	DRV11873	Sensorless	12 V, 1.5 A	TI Website
Texas Instruments	DRV10866	Sensorless	5 V, 680 mA	TI Website
NXP	TDF5140A	Sensorless	20 V, 800 mA	NXP Website