AM9469

Document number: DS38810 Rev. 2 - 2

10 of 16

www.diodes.com

April 2018

© Diodes Incorporated

AM9469

Application Notes (Continued)

Speed Control

This device allows both the DC voltage input and PWM signal input for speed control. Typically, only one of the methods is used to control the

motor speed. In DC voltage speed control mode, the voltage on the VCONT Pin is compared with the CPWM triangular wave to generate

internal PWM signal to drive the output. In PWM speed control mode, the PWM signal on the PWM Pin directly controls the output PWM drive.

The typical application circuits shows the two speed control methods.

1.

Speed Control by PWM Pin

REGH

5VREG

VCONT

RMI

FG

RD

IN1

HB

IN2

CPWM

PWM

GND

3

4

5

6

7

8

14

13

12

11

10

9

RF

OUT2

1

2

16

15

OUT1

Dz

D1

RF

CPWM

Hall

PWM signal for

speed control

C1

SYSTEM

POWER

AM9469

R1

VDD

Motor Coil

2.

Speed Control by VCONT/RMI Pin

REGH

5VREG

VCONT

RMI

FG

RD

IN1

HB

IN2

CPWM

PWM

GND

3

4

5

6

7

8

14

13

12

11

10

9

RF

OUT2

1

2

16

15

OUT1

Dz

D1

RF

CPWM

C1

SYSTEM

POWER

VPWM

Hall

AM9469

R1

VDD

Motor Coil