Apex PA12, PA12A Datasheet

MICROTECHNOLOGY

HTTP://WWW.APEXMICROTECH.COM (800) 546-APEX [phone]

FEATURES

• LOW THERMAL RESISTANCE — 1.4°C/W

• CURRENT FOLDOVER PROTECTION — NEW

• HIGH TEMPERATURE VERSION — PA12H

• EXCELLENT LINEARITY — Class A/B Output

• WIDE SUPPLY RANGE — ±10V to ±50V

• HIGH OUTPUT CURRENT — Up to ±15A Peak

APPLICATIONS

POWER OPERATIONAL AMPLIFIERS

PA12 • PA12A

• MOTOR, VALVE AND ACTUATOR CONTROL

• MAGNETIC DEFLECTION CIRCUITS UP TO 10A

• POWER TRANSDUCERS UP TO 100kHz

• TEMPERATURE CONTROL UP TO 360W

• PROGRAMMABLE POWER SUPPLIES UP TO 90V

• AUDIO AMPLIFIERS UP TO 120W RMS

DESCRIPTION

The PA12 is a state of the art high voltage, very high output
current operational amplifier designed to drive resistive, induc­tive and capacitive loads. For optimum linearity, especially at
low levels, the output stage is biased for class A/B operation
using a thermistor compensated base-emitter voltage multi­plier circuit. The safe operating area (SOA) can be observed
for all operating conditions by selection of user program­mable current limiting resistors. For continuous operation
under load, a heatsink of proper rating is recommended.

This hybrid integrated circuit utilizes thick film (cermet)
resistors, ceramic capacitors and semiconductor chips to
maximize reliability, minimize size and give top performance.
Ultrasonically bonded aluminum wires provide reliable inter­connections at all operating temperatures. The 8-pin TO-3
package is hermetically sealed and electrically isolated. The
use of compressible isolation washers voids the warranty.

EQUIVALENT SCHEMATIC

3

Q3

Q5

Q2A

Q6A

Q2B

Q6B

D1

Q1

Q4

4

A1

5

C1

6

POWER RATING

Not all vendors use the same method to rate the power
handling capability of a Power Op Amp. APEX rates the
internal dissipation, which is consistent with rating methods
used by transistor manufacturers and gives conservative
results. Rating delivered power is highly application depen­dent and therefore can be misleading. For example, the 125W
internal dissipation rating of the PA12 could be expressed as
an output rating of 250W for audio (sine wave) or as 440W if
using a single ended DC load. Please note that all vendors rate
maximum power using an infinite heatsink.

THERMAL STABILITY

APEX has eliminated the tendency of class A/B output
stages toward thermal runaway and thus has vastly increased
amplifier reliability. This feature, not found in most other Power
Op Amps, was pioneered by APEX in 1981 using thermistors
which assure a negative temperature coefficient in the quies­cent current. The reliability benefits of this added circuitry far
outweigh the slight increase in component count.

EXTERNAL CONNECTIONS

R

CL+

TOP VIEW

6

2

7

F.O.

CL+

1

8

CL–

OUT

OUTPUT

R

CL–

+V

S

3

+IN

4

–IN

5

2

–V

S

1
7

8

APEX MICROTECHNOLOGY CORPORATION • TELEPHONE [phone] • FAX [phone] • ORDERS [phone] • EMAIL [e-mail]

PA12 • PA12A

ABSOLUTE MAXIMUM RATINGS

SPECIFICATIONS

ABSOLUTE MAXIMUM RATINGS

SPECIFICATIONS

PARAMETER TEST CONDITIONS
INPUT

OFFSET VOLTAGE, initial TC = 25°C ±2 ±6 ±1 ±3mV
OFFSET VOLTAGE, vs. temperature Full temperature range ±10 ±65 * ±40 µV/°C
OFFSET VOLTAGE, vs. supply TC = 25°C ±30 ±200 * * µV/V
OFFSET VOLTAGE, vs. power TC = 25°C ±20 * µV/W
BIAS CURRENT, initial TC = 25°C ±12 ±30 10 20 nA
BIAS CURRENT, vs. temperature Full temperature range ±50 ±500 * * pA/°C
BIAS CURRENT, vs. supply TC = 25°C ±10 * pA/V
OFFSET CURRENT, initial TC = 25°C ±12 ±30 ±5 ±10 nA
OFFSET CURRENT, vs. temperature Full temperature range ±50 * pA/°C
INPUT IMPEDANCE, DC TC = 25°C200*MΩ
INPUT CAPACITANCE TC = 25°C3*pF
COMMON MODE VOLTAGE RANGE3Full temperature range ±VS –5 ±VS –3 * * V
COMMON MODE REJECTION, DC Full temp. range, VCM = ±VS –6V 74 100 * * dB

GAIN

OPEN LOOP GAIN at 10Hz TC = 25°C, 1KΩ load 110 * dB
OPEN LOOP GAIN at 10Hz Full temp. range, 8Ω load 96 108 * * dB
GAIN BANDWIDTH PRODUCT @ 1MHz
POWER BANDWIDTH TC = 25°C, 8Ω load 13 20 * * kHz
PHASE MARGIN Full temp. range, 8Ω load 20 * °

OUTPUT

VOLTAGE SWING
VOLTAGE SWING
VOLTAGE SWING
CURRENT, peak TC = 25°C1015A
SETTLING TIME to .1% TC = 25°C, 2V step 2 * µs
SLEW RATE TC = 25°C 2.5 4 * * V/µs
CAPACITIVE LOAD Full temperature range, AV = 1 1.5 * nF
CAPACITIVE LOAD Full temperature range, AV > 10 SOA *

POWER SUPPLY

VOLTAGE Full temperature range ±10 ±40 ±45 * * ±50 V
CURRENT, quiescent TC = 25°C2550**mA

THERMAL

RESISTANCE, AC, junction to case
RESISTANCE, DC, junction to case TC = –55 to +125°C 1.25 1.4 * * °C/W
RESISTANCE, junction to air TC = –55 to +125°C30*°C/W
TEMPERATURE RANGE, case Meets full range specification –25 +85 –55 +125 °C

3
3
3

TC = 25°C, 8Ω load 4 * MHz

TC = 25°C, PA12 = 10A, PA12A = 15A
TC = 25°C, IO = 5A ±VS –5 * V
Full temp. range, IO = 80mA ±VS–5 * V

4

TC = –55 to +125°C, F > 60Hz .8 .9 * * °C/W

SUPPLY VOLTAGE, +Vs to –Vs 100V
OUTPUT CURRENT, within SOA 15A
POWER DISSIPATION, internal 125W
INPUT VOLTAGE, differential ±VS –3V
INPUT VOLTAGE, common mode ±V
TEMPERATURE, pin solder -10s 300°C
TEMPERATURE, junction
TEMPERATURE RANGE, storage –65 to +150°C
OPERATING TEMPERATURE RANGE, case –55 to +125°C

2, 5

1

PA12

MIN TYP MAX MIN TYP MAX UNITS

±VS –6 * V

PA12/PA12A

S

200°C

PA12A

NOTES: * The specification of PA12A is identical to the specification for PA12 in applicable column to the left.

APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: [phone]

1. Long term operation at the maximum junction temperature will result in reduced product life. Derate internal power dissipation
to achieve high MTTF.

2. The power supply voltage for all tests is ±40, unless otherwise noted as a test condition.

3. +VS and –VS denote the positive and negative supply rail respectively. Total VS is measured from +VS to –VS.

4. Rating applies if the output current alternates between both output transistors at a rate faster than 60Hz.

5. Full temperature range specifications are guaranteed but not 100% tested.

CAUTION

The internal substrate contains beryllia (BeO). Do not break the seal. If accidentally broken, do not crush, machine, or
subject to temperatures in excess of 850°C to avoid generating toxic fumes.

TYPICAL PERFORMANCE
GRAPHS

PA12 • PA12A

140

POWER DERATING

120
100

80

60
40

PA12 PA12A

20

0

0 20 40 60 80 100 120

INTERNAL POWER DISSIPATION, P(W)

CASE TEMPERATURE, T (°C)

SMALL SIGNAL RESPONSE

120

C

100

80
60

40

20

OPEN LOOP GAIN, A (dB)

0

–20

1 100 10M

10 1K 10K .1M 1M

FREQUENCY, F (Hz)

140

2.5

B

2.2

BIAS CURRENT

1.9

1.6

1.3

1.0
.7

.4

NORMALIZED BIAS CURRENT, I (X)

–25 25 50 75

–50 0 100

CASE TEMPERATURE, T (°C)

PHASE RESPONSE

0

–30
–60

Φ

–90

–120

PHASE, (°)

–150
–180

–210

10 10K 1M

1 100 .1M 10M

1K

FREQUENCY, F (Hz)

17.5

CURRENT LIMIT

15.0

12.5

LIM

RCL = .06 ,RFO =

10.0
R

= .18 ,R

CL

7.5

5.0

V

= –24V

O

CURRENT LIMIT, I (A)

2.5

125

C

0

–50 –25 50 100

CASE TEMPERATURE, T (°C)

Ω

∞

= 0

Ω

FO

V

V

O

V

= 0

O

025 75

= 0

O

= 24V

C

125

POWER RESPONSE

100

68

PP

46

O

32

| +V

22
15

| +V

10

6.8

OUTPUT VOLTAGE, V (V )

4.6
10K 20K 50K .1M

| +V

| + | –V

S

| – | –V

| + | –V

S

| = 80V

S

| = 30V

S

S

30K

FREQUENCY, F (Hz)

| = 100V

S

70K

COMMON MODE REJECTION

120

100

80

60

40

20

0

1 10K

COMMON MODE REJECTION, CMR (dB)

HARMONIC DISTORTION

3

AV =10

1

VS = ±37V

= 4

R

L

1K 1M

FREQUENCY, F (Hz)

Ω

.3

= 4W

O

P

.03

.1

= 100mW

O

P

DISTORTION, (%)

.01

.003

100 1K 3K .1M

= 120W

O

P

300 10K 30K

FREQUENCY, F (Hz)

.1M10 100

PULSE RESPONSE

8
6

O

4

VIN = ±5V, tr = 100ns

2
0

-2

-4

OUTPUT VOLTAGE, V (V)

-6

-8
0

2 4 6 8 10 12

TIME, t (µs)

QUIESCENT CURRENT

1.6

1.4

(X)

Q

1.2

1.0

.8

NORMALIZED, I

.6

.4

40 100

50 60 70 80 90

TOTAL SUPPLY VOLTAGE, V

= –25°C

T

C

= 25°C

T

C

= 85°C

T

C

T

C

= 125°C

S

(V)

100

INPUT NOISE

√

70

N

50
40

30

20

10

INPUT NOISE VOLTAGE, V (nV/ Hz)

10 100 10K .1M

1K

FREQUENCY, F (Hz)

OUTPUT VOLTAGE SWING

6

5

–V

4

0

3

+V

0

2

1

VOLTAGE DROP FROM SUPPLY (V)

3691215

0

OUTPUT CURRENT, I

(A)

O

APEX MICROTECHNOLOGY CORPORATION • TELEPHONE [phone] • FAX [phone] • ORDERS [phone] • EMAIL [e-mail]

PA12 • PA12A

OPERATING

CONSIDERATIONS

GENERAL

Please read Application Note 1, which covers stability, supplies,
heatsinking, mounting, current limit, SOA interpretation, and speci­fication interpretation. Additional information can be found in the
application notes. For information on the package outline, heatsinks,
and mounting hardware, consult the “Accessory and Package
Mechanical Data” section of the handbook.

SAFE OPERATING AREA (SOA)

The output stage of most power amplifiers has three distinct
limitations:

±V

SHORT TO ±V

S

C, L, OR EMF LOAD COMMON

S

50V .30A 2.4A
40V .58A 2.9A

35V .87A 3.7A
30V 1.5A 4.1A
25V 2.4A 4.9A
20V 2.9A 6.3A
15V 4.2A 8.0A

These simplified limits may be exceeded with further analysis using the operat­ing conditions for a specific application.

SHORT TO

1. The current handling capability of the transistor geometry and

the wire bonds.

2. The second breakdown effect which occurs whenever the

simultaneous collector current and collector-emitter voltage
exceeds specified limits.

3. The junction temperature of the output transistors.

The SOA curves combine the effect of all limits for this Power Op

15

10

THERMAL

SS

5.0

3.0

2.0

1.5

1.0
.7
.5

OUTPUT CURRENT FROM +V OR –V (A)

.3

10 20 25 30 35 40 50 60 70

15 80 100

SUPPLY TO OUTPUT DIFFERENTIAL VOLTAGE V –V (V)

T

= 25°C

C

T

= 85°C

C

T

= 125°C

C

SECOND BREAKDOWN

t = 1ms

t = 5ms

t = 0.5ms

steady state

SO

Amp. For a given application, the direction and magnitude of the
output current should be calculated or measured and checked
against the SOA curves. This is simple for resistive loads but more
complex for reactive and EMF generating loads. However, the
following guidelines may save extensive analytical efforts.

1. Capacitive and dynamic* inductive loads up to the following
maximum are safe with the current limits set as specified.

CAPACITIVE LOAD INDUCTIVE LOAD

±V

S

= 5A I

LIM

= 10A I

LIM

= 5A I

LIM

= 10A

LIM

I

50V 200µF 125µF 5mH 2.0mH
40V 500µF 350µF 15mH 3.0mH

35V 2.0mF 850µF 50mH 5.0mH
30V 7.0mF 2.5mF 150mH 10mH
25V 25mF 10mF 500mH 20mH
20V 60mF 20mF 1,000mH 30mH
15V 150mF 60mF 2,500mH 50mH

*If the inductive load is driven near steady state conditions, allowing the output
voltage to drop more than 8V below the supply rail with I
the supply rail with I
must be capacitively coupled or the current limit must be lowered to meet SOA

criteria.

= 5A while the amplifier is current limiting, the inductor

LIM

= 15A or 25V below

LIM

2. The amplifier can handle any EMF generating or reactive load
and short circuits to the supply rail or common if the current
limits are set as follows at T

This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specifications are subject to change without notice.

= 25°C:

C

PA12U REV. M MARCH 1999 © 1999 Apex Microtechnology Corp.

CURRENT LIMITING

Refer to Application Note 9, "Current Limiting", for details of both
fixed and foldover current limit operation. Visit the Apex web site
at www.apexmicrotech.com for a copy of the Power Design
spreadsheet (Excel) which plots current limits vs. steady state
SOA. Beware that current limit should be thought of as a +/–20%
function initially and varies about 2:1 over the range of –55°C to
125°C.

For fixed current limit, leave pin 7 open and use equations 1 and 2.

= 0.65/L

R

CL

= 0.65/R

I

CL

Where:

is the current limit in amperes.

I

CL

is the current limit resistor in ohms.

R

CL

For certain applications, foldover current limit adds a slope to
the current limit which allows more power to be delivered to the
load without violating the SOA. For maximum foldover slope,
ground pin 7 and use equations 3 and 4.

Where:
Vo is the output voltage in volts.

Most designers start with either equation 1 to set R
desired current at 0v out, or with equation 4 to set R
maximum output voltage. Equation 3 should then be used to plot
the resulting foldover limits on the SOA graph. If equation 3 results
in a negative current limit, foldover slope must be reduced. This
can happen when the output voltage is the opposite polarity of the
supply conducting the current.

In applications where a reduced foldover slope is desired, this
can be achieved by adding a resistor (R
ground. Use equations 4 and 5 with this new resistor in the circuit.

Where:

is in K ohms.

R

FO

CL

CL

0.65 + (Vo * 0.014)

= (3)

I

CL

R

CL

0.65 + (Vo * 0.014)

RCL = (4)

I

CL

) between pin 7 and

FO

0.65 + Vo * 0.14

I

10.14 + R

= (5)

CL

R

CL

FO

0.65 + Vo * 0.14

R

10.14 + R

= (6)

CL

I

CL

FO

CL

CL

for the

at the

(1)
(2)