MP6604A

– SIMPLE, DUAL H-BRIDGE DRIVER WITH SEPARATE IN AND EN PINS

MP6604A Rev. 1.1

MonolithicPower.com

13

5/12/2023

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© 2023 MPS. All Rights Reserved.

OPERATION

The MP6604A is a general-purpose dual H-

bridge motor driver that integrates eight N-

channel power MOSFETs connected as four

half H-bridges, with a 2.5A current capability. It

operates across a wide 4.5V to 45V input

voltage (VIN) range.

The MP6604A is designed to drive bipolar

stepper motors, brushed DC motors, solenoids,

or other loads.

nSLEEP and nRESET Operation

Pull nSLEEP low to have the device enter low-

power sleep mode. In sleep mode, the gate

driver charge pump turns off, and all of the

internal circuitry and H-bridge outputs are

disabled. All of the inputs are ignored while

nSLEEP is pulled low.

There is a delay time (600µs) between when

the part exits sleep mode and when the part

starts driving the motor to allow the internal

circuitry to stabilize. The nSLEEP pin has an

internal pull-down resistor.

Pull nRESET low to reset a latched protection

[e.g. over-current protection (OCP) or over-

voltage protection (OVP)] and to have the

outputs enter a high-impedance (Hi-Z) state.

Input Interface

The MP6604A integrates four half H-bridges

that operate independently from one another.

Each output has its own input (AINx/BINx) and

enable (AENx/BENx) pins for each output pin

(AOUTx/BOUTx).

Table

2

shows

the

MP6604A

’s pin logic.

Table 2: MP6604A Pin Logic

AENx/

BENx

AINx/

BINx

AOUTx/

BOUTx

High

x (6)

Hi-Z

Low

Low

Low

Low

High

High

All of the logic inputs have internal pull-down

resistors.

Note:

6)

“x” denotes high or low.

Automatic Synchronous Rectification

If both the high-side MOSFET (HS-FET) and

low-side

MOSFET

(LS-FET)

are

off,

recirculation current should continue to flow

while driving current through an inductive load.

This current passes through the MOSFET body

diodes.

The

MP6604A

employs

automatic

synchronous rectification to reduce excess

power dissipation in the body diodes.

If both the HS-FET and LS-FET are off, and the

voltage on an AOUTx/BOUTx (VAOUTx/VBOUTx)

pin is pulled below GND, then the LS-FET turns

on until its current reaches 0A, or until the HS-

FET is commanded to turn on. Similarly, if

VAOUTx/VBOUTx exceeds VIN, then the HS-FET

turns on until its current reaches 0A, or until the

LS-FET is commanded to turn on.

Internal Supplies (VREG and VCP)

The internal regulator (VREG) provides a 5V

supply for the low-side (LS) gate driver. The

other internal regulator (VCP) provides a supply

5V above VIN for the high-side (HS) gate driver.

VREG and VCP require external capacitors.

Connect a 1µF capacitor between the VREG

pin

and

GND.

Connect

a

1µF

capacitor

between

the

VCP

and

VIN

pins.

Both

capacitors should have X7R dielectrics, and

should be rated for

≥16V.

The charge pump’s flying capacitor (connected

between the CPA and CPB pins) should be a

100nF ceramic capacitor with X7R dielectrics,

and should be rated for at least the maximum

VIN.

Fault Reporting

The MP6604A

’s nFAULT pin reports whether

an over-current (OC), over-temperature (OT), or

over-voltage (OV) fault has occurred. nFAULT

is an open-drain output that is pulled low if a

fault occurs. If used, nFAULT should be pulled

high via an external pull-up resistor.

Over-Current Protection (OCP)

OCP circuitry disables the gate driver to limit

the current flowing through the MOSFETs. If the

current exceeds the OCP threshold for longer