APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL prodlit@apexmicrotech.com

FEATURES

• MONOLITHIC MOS TECHNOLOGY

• LOW COST

• HIGH VOLTAGE OPERATION—150V

• HIGH SLEW RATE—27V/

µs

• HIGH POWER—5A, 85W DISSIPATION

APPLICATIONS

• MAGNETIC DEFLECTION

• PA AUDIO

• MOTOR DRIVE

• NOISE CANCELLATION

DESCRIPTION

The PA45 is a high power monolithic MOSFET operational

amplifier that achieves performance levels unavailable even in

many hybrid amplifier designs. Inputs are protected from

excessive common mode and differential mode voltages as

well as static discharge. The safe operating area (SOA) has no

second breakdown limitations and can be observed with all

type loads by choosing an appropriate current limiting resistor.

External compensation provides the user flexibility in choosing

optimum gain and bandwidth for the application.

This circuit utilizes a beryllia (BeO) substrate to minimize

thermal resistance. Ultrasonically bonded aluminum wires

provide reliable interconnections at all operating tempera-

tures. The 8-pin TO-3 package is hermetically sealed and

electrically isolated. The use of compressible isolation wash-

ers and/or improper mounting torque will void the product

warranty.

EQUIVALENT SCHEMATIC

TYPICAL APPLICATION

PA45

+80

–20

YOKE

±2.5A 7µSec Retrace

Horizontal Deflection Coil Amplifiers

1

6

5

4

3

2

7

8

Horizontal deflection amplifiers require both high speed and

low distortion. The speed at which current can be changed in a

deflection coil is a function of the voltage available from the op

amp. In this application an 80 volt power supply is used for the

retrace polarity to provide a 7

µSec retrace time, half of which is

required for amplifier slewing. This circuit can perform 15.75

KHz deflection in up to 50

µH coils at up to 5A p-p.

PHASE

COMPENSATION

Gain

C

C

R

C

≥10

10pF

1K

Ω

≥1

68pF

1K

Ω

CC1

CC2

2

7

3

5

4

6

8

1

Q19

Q17

Q16

Q15

Q14

Q9

Q10

Q7

D7

Q21

Q20

+IN

–IN

Q11

Q12

D4

D2

Q3

D3

D5

Q8

Q13

Q24

D1

Q2

Q5

Q6

CURRENT

SENSE

OUTPUT

DRIVE

PATENTED

EXTERNAL CONNECTIONS

TOP VIEW

1

2

3

4

5

6

7

8

+IN

OUTPUT

DRIVE

–IN

CC2

C

IS NPO RATED

FOR FULL SUPPLY VOLTAGE.

C

OUTPUT

CURRENT

SENSE

CC1

+V

S

C

C

R

C

HTTP://WWW.APEXMICROTECH.COM

(800) 546-APEX

(800) 546-2739

MICROTECHNOLOGY

HIGH VOLTAGE POWER OPERATIONAL AMPLIFIER

PA45