P r o d u c t I n n o v a t i o n F r o m

MSA240

MSA240U

1

MSA240

Pulse Width Modulation Amplifiers

MSA240

P r o d u c t I n n o v a t i o n F r o m

FEATURES

• LOW COST

• HIGH VOLTAGE - 100 VOLTS

• HIGH OUTPUT CURRENT - 20 AMPS

• 2kW OUTPUT CAPABILITY

• VARIABLE SWITCHING FREQUENCY

APPLICATIONS

• BRUSH MOTOR CONTROL

• MRI

• MAGNETIC BEARINGS

• CLASS D SWITCHMODE AMPLIFIER

DESCRIPTION

The MSA240 is a surface mount constructed PWM amplifier

that provides a cost effective solution in many industrial applica-

tions. The MSA240 offers outstanding performance that rivals

many much more expensive hybrid components. The MSA240

is a complete PWM amplifier including an oscillator, comparator,

error amplifier, current limit comparators, 5V reference, a smart

controller and a full bridge output circuit.The switching frequency

is user programmable up to 50 kHz. The MSA240 is built on a

thermally conductive but electrically insulating substrate that

can be mounted to a heatsink.

EQUIVALENT CIRCUIT DIAGRAM

58-PIN DIP

PACKAGE STYLE KC

TYPICAL APPLICATION

TORQUE MOTOR CONTROL

With the addition of a few external components the MSA240

becomes a motor torque controller. In the MSA240 the source

terminal of each low side MOSFET driver is brought out for

that amplifies the difference in currents of the two half bridges.

This signal is fed into the internal error amplifier that mixes the

current signal and the control signal. The result is an input

signal to the MSA240 that controls the torque on the motor.

EXTERNAL CONNECTIONS

49-53

A OUT

35-39

B OUT

Is B

Is A

Rs B

Rs A

40-43

54-57

CONTROL

SIGNAL

15

2,18,26

DIG

RET

PWR

GND

58

ROSC

A1

PWM AMPLIFIER

+5V REF OUT

CLK OUT

17

22

24

20

1

RRAMP IN

CLK/2 OUT

ROSC

RRAMP

E/A OUT

16

2.5V

E/A -IN

E/A +IN

19

SINGLE POINT GND @ 26

+IN

13

2.5V

SIG

GND

AC

BACK

PLATE

28

23

C2 IS ELECTROLYTIC ≥10UF PER AMP OUTPUT CURRENT

C1,3 HIGH QUALITY CERAMIC ≥1.0UF

ALL +Vs MUST BE TIED TOGETHER

ALL SIG GND PINS MUST BE TIED TOGETHER

SINGLE POINT GROUND @ PIN 26

VIEW FROM

COMPONENT SIDE

+

SINGLE

POINT

GND

C3

C1

C2

NOTES:

54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34

5

10

9

8

7

6

15

14

13

12

11

20

19

18

17

16

25

24

23

22

21

26 27 28

2

1

4

3

+Vs

A OUT

+Vs

B OUT

PWR

GND

33 32

30 29

31

55

56

58 57

GND

+IN

A OUT

I SENSE B

+Vs

I SENSE A

35-39

54-57

40-43

58

1

13

5V

SIGNAL

R3

R2

29

PWR

+Vs

44-48

49-53

B OUT

SMART

CONTROLLER

GND

-

+

-

+

-

+

200mV

REF

OUT

20

CLK/2 OUT

21

CLK IN

OSC

CLK OUT

24

22

7

10

CLK/2

-

+

17

16

15

E/A OUT

E/A -IN

E/A +IN

30-34

SIGNAL

GND

26

SIGNAL

GND

18

2

27

APEX TP

DIGITAL

RETURN

23

2200pF

2200pF

1K

1K

.01F

.01F

2.68K

28

AC BACK

PLATE

1F

BACK PLATE

Q1

D2

D1

Q4

Q3

Q2

5.36K

Copyright © Cirrus Logic, Inc. 2009

(All Rights Reserved)

http://www.cirrus.com

MAY 2009

APEX − MSA240UREVD