The H bridge motor controller MP6550 (ART546bE)

A key component for applications using brushed DC motors is the H bridge driver. In this article we focus on MPS's MP6550 (Monolhitc Power Systems) for 2A currents. This article is based on the component datasheet.

Note: the component datasheet access link through Mouser Electronics that provides it is: https://br.mouser.com/pdfDocs/MP6550.pdf 

The MP6550 from MPS consists of a brushed DC motor driver that can operate with voltages from 1.8V to 22V. The component is available in a 12-pin housing as shown in figure 1.

 

Figure 1 - The housing measuring only 2 x 2 mm
Figure 1 - The housing measuring only 2 x 2 mm

 

 

The applications indicated by the manufacturer include:

- Robotics

- Cameras

- Toys

- Consumer products

- Medical devices

The MP6550 integrated circuit already includes a power MOSFET with a driving resistance of just 240mOhm. It also features thermal shutdown and short circuit protection.

Interfacing is compatible with most control devices on the market. In figure 2 we have a typical application circuit for this component.

 

Figure 2 - Application circuit
Figure 2 - Application circuit

 

Figure 3 shows the functional block diagram of this component for a channel.

 

Figure 3 - Functional diagram
Figure 3 - Functional diagram

 

In operation, the logic levels of the inputs determine the operating mode of the motor according to the table shown below.

 


 

 

For the PWM control input we have the following operating table.

 


 

 

In addition, the device has some interesting features such as motor braking, protection circuits, overcurrent, undervoltage and current sensing.

The graph in figure 4 shows the typical performance of this control.

 

Figure 4 - Normal operation
Figure 4 - Normal operation

 

In the datasheet you can find many other performance graphs, in addition to features, of which we highlight some:

- Has 3.3 V reference output

- PWM input compatible with industry standards up to 100 kHz

- Low standby current

- Internal charge pump

 

 


Circuit Bench