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Datasheet

Datasheet

BD6722FS

TSZ02201-0H1H0B100180-1-2

© 2012 ROHM Co., Ltd. All rights reserved.

28.JUL.2012 Rev.002

www.rohm.com

TSZ22111・15・001

●Application circuit example(Constant values are for reference)

Substrate design note

a) Motor power and ground lines are made as fat as possible.

b) IC power line is made as fat as possible.

c) IC ground line is common with the application ground except motor ground (i.e. hall ground etc.), and arranged

near to (–) land.

d) The bypass capacitors (Vcc side and Vm side) are arrangement near to Vcc terminal and FETs, respectively.

e) H+ and H– lines are arranged side by side and made from the hall element to IC as shorter as possible,

because it is easy for the noise to influence the hall lines.

Fig.21 PWM controllable 4 wires type (FG) motor application circuit

Protection of FG open-drain

Stabilization of REF voltage

Hall bias is set according to the

amplitude of hall element

output and hall input voltage

range.

Noise measures of substrate

Drive the PMOS FET gate by

constant current flowing to IC

Adjustment the PMOS FET

slew rate

Low-pass filter for RNF voltage

smoothing

So bypass capacitor,

arrangement near to FETs as

much as possible

So bypass capacitor,

arrangement near to Vcc

terminal as much as possible

Reverse-connected prevention

of the FAN connector

Reverse-connected prevention

of the FAN connector

Circuit that converts PWM duty

into DC voltage

Minimum output duty setting

Output PWM frequency setting

To limit motor current, the

current is detected.

Note the power consumption of

detection resistance.

Maximum output voltage and

current are 34V and 1.5A.

H

SIG

0

Ω to

330pF

to 1000pF

0.1µF to

PWM

＋

M

470

Ω to 1kΩ

0

Ω to 2kΩ

1µF to

1µF to

－

200

Ω

to 20k

Ω

100pF

to 0.1µF

0.24

Ω to

Vcc

HALL

AMP

Vcl

SIGNAL

OUTPUT

HALL

COMP

CONTROL

LOGIC

PRE-

DRIVER

REF

OSC

QUICK

START

LOCK

PROTECT

TSD

PWM SOFT

SWITCHING

CURRENT

LIMIT COMP

SIGNAL

OUTPUT

PWM

COMP

PWM

COMP

H–

H+

MIN

TH

OSC

AL

REF

A1L

CS

RNF

GND

A2H

A2L

FG

10

9

14

13

12

11

16

15

1

2

3

4

5

6

7

8

Vcc

A1H