Three-Phase Sensorless Fan Driver

A4941

2

Allegro MicroSystems, Inc.

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

Pin-out Diagram

Absolute Maximum Ratings

Characteristic

Symbol

Notes

Rating

Unit

Supply Voltage

20

V

Logic Input Voltage Range

PWM, SLEW

–0.3 to 5.5

V

FC

V

Logic Output Voltage

FG

V

Output Current

Peak (startup and lock rotor)

1.25

A

rms, duty cycle = 100%

900

mA

Operating Ambient Temperature

G temperature range

–40 to 105

ºC

Maximum Junction Temperature

150

ºC

Storage Temperature

–55 to 150

ºC

Terminal List Table

Name

Number

Function

CP1

2

Charge pump

CP2

3

Charge pump

CTAP

12

Motor terminal center tap

FC

10

Logic input

FG

8

Speed output signal

GND

5, 11

Ground

OUTA

15

Motor terminal A

OUTB

16

Motor terminal B

OUTC

1

Motor terminal C

PWM

7

Logic input

SENSE

14

Sense resistor connection

SLEW

6

Logic input

TEST

9

Test use only, leave open circuit

VBB

13

Input supply

VCP

4

Charge pump

Selection Guide

Part Number

Application

Packing

A4941GLPTR-T

Commerical/Industrial

4000 pieces per 13-in. reel

A4941GLPTR-A-T

Automotive

4000 pieces per 13-in. reel

Characteristic

Symbol

Test Conditions*

Value

Unit

Package Thermal Resistance

On 4-layer PCB based on JEDEC standard

34

ºC/W

52

ºC/W

*Additional thermal information available on the Allegro website

Recommended Operating Conditions

Characteristic

Symbol

Conditions

Min.

Typ.

Max.

Unit

Supply Voltage

5

–

16

V

Output Current

Peak (startup and lock rotor)

–

–

1

A

Run current

–

<500

–

mA

OUTC

CP1

CP2

VCP

GND

SLEW

PWM

FG

OUTB

OUTA

SENSE

VBB

CTAP

GND

FC

TEST

1

2

3

4

5

6

7

8

16

15

14

13

12

11

10

9

PAD