MP6551

– 14V, 5A, H-BRIDGE MOTOR DRIVER

MP6551 Rev. 1.0

MonolithicPower.com

12

7/7/2021

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APPLICATION INFORMATION

External Component Selection

Bypass the VIN pin to GND using a 100nF

ceramic X7R capacitor located as close to the

IC as possible. Place an additional 1µF to 10µF

ceramic capacitor nearby the 100nF capacitor.

Depending on the supply impedance and

distance

to

other

large

capacitors,

an

electrolytic bulk capacitor may also be required

to stabilize VIN. The CM1 and CM2 pins are

current measurement outputs. CM1 and CM2

are typically converted to a voltage via a

termination

resistor

(RREF)

that

creates

a

reference voltage (VREF). A resistor divider

connected between the ADC supply and GND

can provide a ratiometric voltage for an AC/DC

converter.

PCB Layout Guidelines

Efficient

PCB

layout

is

critical for

stable

operation. For the best results, refer to Figure 3

and follow the guidelines below:

1. Bypass VIN to GND using a 100nF ceramic

X7R capacitor located as close to the IC as

possible.

2. Place an additional 1µF to 10µF ceramic

capacitor nearby the 100nF capacitor. An

electrolytic bulk capacitor may be required

to stabilize VIN.

3. The VIN, OUT1, and OUT2 pins dissipate

heat from the motor driver. To reduce heat

on the device, add as many copper planes

to these pins as possible.

4. Solid planes on the inner layers of the

device can also dissipate heat.

Place

multiple thermal vias on the VIN, OUTx, and

GND copper planes to dissipate heat from

the outer layers to the copper plane(s).

Figure 3: Recommended PCB Layout