Datasheet PA61A, PA61 Datasheet (Apex)

MICROTECHNOLOGY

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

FEATURES

• WIDE SUPPLY RANGE — ±10 to ±45V

• HIGH OUTPUT CURRENT — ±10A Peak

• LOW COST — Class “C” output stage

• LOW QUIESCENT CURRENT — 3mA

APPLICATIONS

POWER OPERATIONAL AMPLIFIERS

PA61 • PA61A

• PROGRAMMABLE POWER SUPPLY

• MOTOR/SYNCRO DRIVER

• VALVE AND ACTUATOR CONTROL

• DC OR AC POWER REGULATOR

• FIXED FREQUENCY POWER OSCILLATOR

DESCRIPTION

The PA61 and PA61A are high output current operational
amplifiers designed to drive resistive, inductive and capacitive
loads. Their complementary emitter follower output stage is
the simple class C type and optimized for low frequency
applications where crossover distortion is not critical. These
amplifiers are not recommended for audio, transducer or
deflection coil drive circuits above 1kHz or when distortion is
critical. The safe operating area (SOA) is fully specified and
can be observed for all operating conditions by selection of
user programmable current limiting resistors. Both amplifiers
are internally compensated for all gain settings. For continu­ous operation under load, mounting on a heatsink of proper
rating is recommended.

This hybrid circuit utilizes thick film conductors, 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 electri­cally isolated and hermetically sealed. The use of compres­sible thermal washers and/or improper mounting torque voids
the product warranty. Please see “General Operating Consid­erations”.

EQUIVALENT SCHEMATIC

3

Q1A

Q1B

2

4

A1

5

C1

6

Q3

Q4

Q6A

1

8

Q6B

R

F1

SENSE HI

+42V

±10V

R

DAC

FIGURE 1. PROGRAMMABLE POWER SUPPLY
WITH REMOTE SENSING

IN1

R

IN2

PA61

–42V

R

CL+

R

CL–

R

F2

R

W

OUT

RW

LOAD

SENSE LO

RTN

TYPICAL APPLICATION

Due to its high current drive capability, PA61 applications
often utilize remote sensing to compensate IR drops in the
wiring. The importance of remote sensing increases as accu­racy requirements, output currents, and distance between
amplifier and load go up. The circuit above shows wire
resistance from the PA61 to the load and back to the local
ground via the power return line. Without remote sensing, a

7.5A load current across only 0.05 ohm in each line would
produce a 0.75V error at the load.

With the addition of the second ratio matched R

F/RIN

pair and
two low current sense wires, IR drops in the power return line
become common mode voltages for which the op amp has a
very high rejection ratio. Voltage drops in the output and power
return wires are inside the feedback loop. Therefore, as long
as the Power Op Amp has the voltage drive capability to
overcome the IR losses, accuracy remains the same. Applica­tion Note 7 presents a general discussion of PPS circuits.

EXTERNAL CONNECTIONS

R

CL+

C

L+

3

TOP VIEW

6

S

2

7

N.C.

OUT

1

R

8

CL–

C

L–

OUTPUT

+IN

–IN

+V

S

4

5

–V

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PA61 • PA61A

ABSOLUTE MAXIMUM RATINGS

SPECIFICATIONS

ABSOLUTE MAXIMUM RATINGS

SUPPLY VOLTAGE, +VS to –V
OUTPUT CURRENT, within SOA 10A

S

90V

POWER DISSIPATION, internal 97W
INPUT VOLTAGE, differential ±VS–3V
INPUT VOLTAGE, common mode ±V
TEMPERATURE, pin solder-10s 300°C
TEMPERATURE, junction

1

S

200°C
TEMPERATURE RANGE, storage –65 to +150°C
OPERATING TEMPERATURE RANGE, case –55 to +125°C

SPECIFICATIONS

PARAMETER TEST CONDITIONS

PA61

2

MIN TYP MAX MIN TYP MAX UNITS

PA61A

INPUT

OFFSET VOLTAGE, initial TC = 25°C ±2 ±6 ±1 ±3mV
OFFSET VOLTAGE, vs. temperature Specified 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 1230 1020nA
BIAS CURRENT, vs. temperature Specified 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 Specified temperature range ±50 * pA/°C
INPUT IMPEDANCE, DC TC = 25°C 200 * MΩ
INPUT CAPACITANCE TC = 25°C3*pF
COMMON MODE VOLTAGE RANGE3Specified temperature range ±VS–5 ±VS–3** V
COMMON MODE REJECTION, DC

3

Specified temperature range 74 100 * * dB

GAIN

OPEN LOOP GAIN at 10Hz Full temp. range, full load 96 108 * * dB
GAIN BANDWIDTH PRODUCT at 1MHz TC = 25°C, full load 1 * MHz
POWER BANDWIDTH TC = 25°C, IO = 8A, VO = 40V
PHASE MARGIN Full temperature range 45 * °

PP

10 16 * * kHz

OUTPUT

VOLTAGE SWING
VOLTAGE SWING
VOLTAGE SWING

3
3
3

TC = 25°C, IO = 10A ±VS–7 ±VS–5 ±VS–6* V
Full temp. range, IO = 4A ±VS–6 ±VS–4** V

Full temp. range, IO = 68mA ±VS–5* V
CURRENT TC = 25°C ±10 * A
SETTLING TIME to .1% TC = 25°C, 2V step 2 * µs
SLEW RATE TC = 25°C, RL = 6Ω 1.0 2.8 * * V/µs
CAPACITIVE LOAD, unit gain Full temperature range 1.5 * nF
CAPACITIVE LOAD, gain>4 Full temperature range SOA *

POWER SUPPLY

VOLTAGE Full temperature range ±10 ±32 ±45 * * * V
CURRENT, quiescent TC = 25°C310**mA

THERMAL

RESISTANCE, AC, junction to case

4

F > 60Hz 1.0 1.2 * * °C/W
RESISTANCE, DC, junction to case F < 60Hz 1.5 1.8 * * °C/W
RESISTANCE, junction to air 30 * °C/W
TEMPERATURE RANGE, case Meets full range specification –25 25 +85 * * * °C

NOTES: * The specification of PA61A is identical to the specification for PA61 in applicable column to the left.

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 specifications is the TYP rating unless 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.

CAUTION

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

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

PA61 • PA61A

100

80

POWER DERATING

T = T

C

60

40

20

0

0 25 50 75 100 125 150

INTERNAL POWER DISSIPATION, P (W)

TEMPERATURE, T (°C)

C

SMALL SIGNAL RESPONSE

120
100

(dB)

OL

80
60

40

20

0

OPEN LOOP GAIN, A

–20

10 1K 10K .1M 1M

1 100 10M

FREQUENCY, F (Hz)

OUTPUT VOLTAGE SWING

5.5

5.0

4.5

4.0

3.5

3.0

2.5

VOLTAGE DROP FROM SUPPLY (V)

0

0

–30
–60
–90

Φ

–120

PHASE, (°)

–150
–180

–210

1 100 .1M 10M

= –25°C

C

T

= 25

C

T

246810

OUTPUT CURRENT, I

°C

° to 85

PHASE RESPONSE

10 10K 1M

1K

FREQUENCY, F (Hz)

7

CURRENT LIMIT

6
5

LIM

R

C

= .12 Ω

L

4
3

R

= 0.3

CL

2

CURRENT LIMIT, I (A)

1
0

025 75

(A)

O

–25 50 100

CASE TEMPERATURE, T (°C)

POWER RESPONSE

80

Ω

125

C

VS = ±40V

58

PP

O

41

RL = 8Ω

30

21
15

11

OUTPUT VOLTAGE, V (V )

8

10K

RL = 3Ω

20K 30K 50K

70K

.1M

FREQUENCY, F (Hz)

PULSE RESPONSE

8

AV = +1

6
4

O

RL = 5

2
0

–2
–4
–6

OUTPUT VOLTAGE, V (V)

–8

2 4 6 8 10 12

0

TIME, t (µs)

HARMONIC DISTORTION

10

= ±36

V

S

Ω

R

= 4

L

3

= 10

A

V

1

O

P

= .1W

.3

= 5W

O

.1

DISTORTION, (%)

.03
.01

P

= 50W

O

P

30 300 1K 10K100 30K

3K

FREQUENCY, F (Hz)

COMMON MODE REJECTION

Ω

120

100

2.5

(X)

B

2.2

BIAS CURRENT

1.9

80
60

1.6

1.3

14

40

20

0

1 10K

COMMON MODE REJECTION, CMR(dB)

(X)

Q

1.6

FREQUENCY, F (Hz)

QUIESCENT CURRENT

1K 1M

.1M10 100

1.4

1.2

°C

= 125

T

1.0

.8

C

T

C

= 25°C

= –55°C

C

T

1.0
.7

.4

NORMALIZED BIAS CURRENT, I

–50

0 100

–25 25 50

75

CASE TEMPERATURE, T (°C)

100

√

70

N

50

INPUT NOISE

40
30

20

125

C

.6

.4

NORMALIZED QUIESCENT CURRENT, I

40

3020

50 60 70 80 90

TOTAL SUPPLY VOLTAGE, V

S

(V)

10

INPUT NOISE VOLTAGE, V (nV/ Hz)

10 100 10K .1M

1K

FREQUENCY, F (Hz)

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

PA61 • PA61A

GENERAL

Please read Application Note 1 "General Operating Consid­erations" which covers stability, supplies, heat sinking, mount­ing, current limit, SOA interpretation, and specification inter­pretation. Visit www.apexmicrotech.com for design tools that
help automate tasks such as calculations for stability, internal
power dissipation, current limit and heat sink selection. The
"Application Notes" and "Technical Seminar" sections contain
a wealth of information on specific types of applications.
Package outlines, heat sinks, mounting hardware and other
accessories are located in the "Packages and Accessories"
section. Evaluation Kits are available for most Apex product
models, consult the "Evaluation Kit" section for details. For the
most current version of all Apex product data sheets, visit
www.apexmicrotech.com.

SAFE OPERATING AREA (SOA)

The output stage of most power amplifiers has 3 distinct
limitations:

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.

10

(A)

8.0

S

6.0

4.0

OR –V

3.0

S

2.0

1.5

1.0
.8

.6
.4

.3
.2

.1

INPUT CURRENT FROM +V

10 20 30

SUPPLY TO OUTPUT DIFFERENTIAL VOLTAGE V

The SOA curves combine the effect of all limits for this Power
Op 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. The following guidelines may save extensive analytical
efforts.

SAFE OPERATING AREA (SOA)

Tc=25°C

Tc=85°C

Tc=125°C

2515

t=0.5ms

t=1m

s

t=5ms

Steady State

40 50 60 70 9080

– VO (V)

S

OPERATING

CONSIDERATIONS

1. Under transient conditions, capacitive and dynamic* induc­tive loads up to the following maximum are safe:

CAPACITIVE LOAD INDUCTIVE LOAD

V

I

= 5A I

S

LIM

45V 200 F 150 F 8mH 2.8mH
40V 400 F 200 F 11mH 4.3mH
35V 800 F 400 F 20mH 5.0mH
30V 1600 F 800 F 35mH 6.2mH
25V 5.0mF 2.5mF 50mH 15mH
20V 10mF 5.0mF 400mH 20mH
15V 20mF 10mF ** 100mH

* 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
I

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

LIM

should be capacitively coupled or the current limit must be
lowered to meet SOA criteria.

** Second breakdown effect imposes no limitation but thermal

limitations must still be observed.

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

±V

C, L, OR EMF LOAD COMMON

S

45V 0.1A 1.3A
40V 0.2A 1.5A
35V 0.3A 1.6A
30V 0.5A 2.0A
25V 1.2A 2.4A
20V 1.5A 3.0A
15V 2.0A 4.0A

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

3. The output stage is protected against transient flyback.
However, for protection against sustained, high energy
flyback, external fast-recovery diodes should be used.

= 10A I

LIM

= 10A or 15V below the supply rail with

LIM

SHORT TO V

= 5A I

LIM

± SHORT TO

S

=85°C.

C

LIM

= 10A

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.

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

PA61U REV. H JANUARY 2001 © 2001 Apex Microtechnology Corp.