CIRRUS PA95_10

PA95
PA95
®
ct Innovation From
P r o d uPA95
High Voltage Power Operational Amplifiers
FEATURES
DESCRIPTION
The PA95 is a high voltage, MOSFET operational amplifier designed as a low cost solution for driving continuous output currents up to 100mA and pulse currents
up to 200mA into capacitive loads. The safe operating area (SOA) has no second breakdown limitations
and can be observed for all load types by choosing
an appropriate current limiting resistor. The MOSFET
output stage is biased AB for linear operation. External compensation provides flexibility in choosing bandwidth and slew rate for the application. Apex Precision
Power’s Power SIP package uses a minimum of board
space allowing for high density circuit boards. The
Power SIP package is electrically isolated. Isolating
thermal washers (TW13) are recommended to prevent
arcing from pins to heatsink.
♦ HIGH VOLTAGE — 900V (±450V)
♦ LOW QUIESCENT CURRENT — 1.6mA
♦ HIGH OUTPUT CURRENT — 100mA ♦ PROGRAMMABLE CURRENT LIMIT
APPLICATIONS
♦ HIGH VOLTAGE INSTRUMENTATION
♦ PROGRAMMABLE POWER SUPPLIES UP
TO ±430V
♦ MASS SPECTROMETERS
♦ SEMICONDUCTOR MEASUREMENT
EQUIPMENT
EQUIVALENT SCHEMATIC
12
+VS
R1A
C2
R1B
Q1
R3
Q3
Q2
Q6
Q5A
1
–IN
6
CC2
4
CC1
Q5
R4
ILIM
8
Q8
Q5B
R7
Q14
R11
R12
Q29
2
+IN
Q21
R19
R20
–VS
10
R27
EXTERNAL CONNECTIONS
+IN
CC1
1
2
4
CC2 OUT ILIM
6
CC
7
8
RLIM
–Vs
+Vs
10
12
*
*
* 0.01µF or greater ceramic power supply bypassing required.
PA95U
www.cirrus.com
Q14
Q30
Q29
–IN
7
OUT
R10
R9
Q4
PATENTED
8-pin SIP
PACKAGE
STYLE DQ
Formed leads available
See package style EC
Copyright © Cirrus Logic, Inc. 2010
(All Rights Reserved)
MAR20101
APEX − PA95UREVL
®
PA95
Product Innovation From
CHARACTERISTICS AND SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Max
Units
SUPPLY VOLTAGE, +VS to -VS
Parameter
Symbol
Min
900
V
OUTPUT CURRENT, source, sink, within SOA
200
mA
30
W
20
V
POWER DISSIPATION, continuous @ TC = 25°C
INPUT VOLTAGE, differential
-20
INPUT VOLTAGE, common mode (Note 3)
-VS
VS
V
TEMPERATURE, pin solder, 10s max.
260
°C
TEMPERATURE, junction (Note 2)
150
°C
TEMPERATURE RANGE, storage
−40
85
°C
OPERATING TEMPERATURE RANGE, case
−25
85
°C
CAUTION
The PA95 is constructed from MOSFET transistors. ESD handling procedures must be observed.
The exposed substrate contains beryllia (BeO). Do not crush, machine, or subject to temperatures
in excess of 850°C to avoid generating toxic fumes.
SPECIFICATIONS
Parameter
Test Conditions1
Min
Typ
Max
Units
INPUT
OFFSET VOLTAGE, initial
0.5
5
mV
15
50
µV/°C
OFFSET VOLTAGE vs. supply
10
25
OFFSET VOLTAGE vs. time
75
BIAS CURRENT, initial
200
OFFSET VOLTAGE vs. temperature
Full temperature range
BIAS CURRENT vs. supply
4
OFFSET CURRENT, initial
50
INPUT RESISTANCE, DC
10
INPUT CAPACITANCE
11
4
COMMON MODE VOLTAGE RANGE
(Note 3)
VS=±250V
±VS Ŧ 30
COMMON MODE REJECTION, DC
VCM = ±90V
80
NOISE
10KHz bandwidth, RS = 1KΩ
µV/V
µV/kHz
2000
pA
pA/V
500
pA
Ω
pF
V
98
dB
2
µV RMS
GAIN
OPEN LOOP @ 15Hz
RL = 5KΩ
118
dB
GAIN BANDWIDTH PRODUCT @ 1MHz
RL = 5KΩ
94
10
MHz
POWER BANDWIDTH
RL = 5KΩ
20
kHz
PHASE MARGIN, A V = 10
Full temp range
60
°
OUTPUT
VOLTAGE SWING
IO = 70mA
CURRENT, continuous
±VS Ŧ 20
100
SLEW RATE, A V = 100
CC =4.7pF
SETTLING TIME, to 0.1%
RESISTANCE
2
±VS Ŧ 24
V
mA
30
V/µS
2V Step
1
µS
no load
100
Ω
PA95U
®
PA95
Product Innovation From
Parameter
Test Conditions1
Min
Typ
Max
Units
±50
±300
±450
V
1.6
2.2
mA
RESISTANCE, AC, junction to case (Note 4) Full temp range, F > 60Hz
2.5
°C/W
RESISTANCE, DC, junction to case
Full temp range, F < 60Hz
4.2
°C/W
RESISTANCE, junction to air
Full temp range
POWER SUPPLY
VOLTAGE (Note 5)
CURRENT, quiescent
THERMAL
30
TEMPERATURE RANGE, case
-25
°C/W
+85
°C
NOTES: 1. Unless otherwise noted: TC = 25°C, DC input specifications are ± value given. Power supply voltage
is typical rating. Cc= 4.7pF.
2. Long term operation at the maximum junction temperature will result in reduced product life. Derate
internal power dissipation to achieve high MTTF.
3. Although supply voltages can range up to ± 450V the input pins cannot swing over this range. The
input pins must be at least 30V from either supply rail but not more than 500V from either supply rail.
See text for a more complete description of the common mode voltage range.
4. Rating applies if the output current alternates between both output transistors at a rate faster than
60Hz.
5. Derate max supply rating .625 V/°C below 25°C case. No derating needed above 25°C case.
QUIESCENT CURRENT, I (X)
1.08
-135
15
10
T = TA
-315
100
60
CC = 4.7pF
200
120
PA95U
100
70
50
100 1K 10K 100K 1M 10M
FREQUENCY, F (Hz)
CURRENT LIMIT
=
85
5°C
24
M +VS OR –VS, (mA)
20
°C
TC
TC
16
40
=2
TC =
C
–55°
8
4
.92
OUTPUT VOLTAGE SWING
40
32
80
.96
.88
400 600
0
200
800 1000
TOTAL SUPPLY VOLTAGE, VS (V)
2M
3M 4M 5M
FREQUENCY, F (Hz)
C
SMALL SIGNAL RESPONSE
-360
1M
12
5°
25 50 75 100 125 150
TEMPERATURE, T (°C)
=
0
-270
C
0
1.00
CC = 4.7pF
-225
T
5
-180
0
250
200
100
DC
DC
,T
C
10
0m
,T
C
=
S
0m
S
=
50
10K
20
15
10
25
°
CC = 4.7pF
100
SAFE OPERATING AREA
20
POWER RESPONSE
500
100
20
40
60
80
OUTPUT CURRENT, IO (mA)
150
50
1K
OUTPUT VOLTAGE, VO (VP-P)
PHASE, Ф (°)
20
QUIESCENT CURRENT
1.04
AGE, VN (nV/√Hz)
T = TC
0
10
MIT, ILIM (mA)
PHASE RESPONSE
-90
25
120
OPEN LOOP GAIN, A (dB)
POWER DERATING
30
VOLTAGE DROP FROM SUPPLY, VS – VO (V)
INTERNAL POWER DISSIPATION, P(W)
TYPICAL PERFORMANCE GRAPHS
7
100K
FREQUENCY, F (Hz)
300K
INPUT NOISE
3
PA95
0
10
CURRENT LIMIT, ILIM (mA)
200
100 1K 10K 100K 1M 10M
FREQUENCY, F (Hz)
CURRENT LIMIT
120
100
70
50
30
20
10
3 5
10
20
50 100 150
CURRENT LIMIT RESISTOR, RCL (Ω)
TC
16
=2
5°C
= –5
TC
8
®
4
Product Innovation From
0
250
100
50
10K
SAFE OPERATING AREA
100
DC
DC
50
,T
C
,T
DC
,T
C
15
C
=
10
=
S
=
85
12
°C
5°
C
10
PULSE CURVES @
5 10% DUTY CYCLE MAX
50
100
200
500
1K
SUPPLY TO OUTPUT DIFFERENTIAL, VS –VO (V)
7
5
3
2
10
PHASE COMPENSATION
CC rated for full supply voltage.
GAIN
CC
≥100
4.7pF
100
1K
10K
FREQUENCY, F (Hz)
1M
RF
TYPICAL APPLICATION
Piezo positioning may be applied to the focusing of segmented mirror systems. The composite mirror may be
composed of hundreds of elements, each requiring focusing under computer control. In such complex systems the
PA95 reduces the costs of power supplies and cooling
with its advantages of low cost and low quiescent power
consumption while increasing circuit density with the SIP
package.
INPUT NOISE
10
25
°C
300K
15
S
0m
100K
FREQUENCY, F (Hz)
20
0m
20
CC = 4.7pF
200
100
20
40
60
80
OUTPUT CURRENT, IO (mA)
150
25
OUTPUT VOLTAGE
20
5°C
24
INPUT NOISE VOLTAGE, VN (nV/√Hz)
40
VOLTAGE DROP FROM SU
CC = 4.7pF
60
OUTPUT CURRENT FROM +VS OR –VS, (mA)
OPEN LOOP GAI
80
+VS
R IN
1
12
PIEZO DRIVE
PA95
2
COMPUTER
FOCUS
COMMAND
VOLTAGE
8
10
7
V OUT
R CL
–V S
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.cirrus.com for design tools
that help automate tasks such as calculations for stability, internal power dissipation, current limit; heat sink selection; Apex Precision Power’s complete Application Notes library; Technical Seminar Workbook; and Evaluation Kits.
CURRENT LIMIT
For proper operation, the current limit resistor (RLIM) must be connected as shown in the external connection diagram. The minimum value is 3.5 ohm, however for optimum reliability the resistor value should be set as high as
possible. The value is calculated as follows; with the maximum practical value of 150 ohms.
.7 RLIM = ILIM
COMMON MODE INPUT RANGE
Operational amplifiers are usually designed to have a common mode input voltage range that approximates the
power supply voltage range. However, to keep the cost as low as possible and still meet the requirements of most
applications the common mode input voltage range of the PA95 is restricted. The input pins must always be a least
30V from either supply voltage but never more than 500V. This means that the PA95 cannot be used in applications
where the supply voltages are extremely unbalanced. For example, supply voltages of +800V and –100V would not
be allowed in an application where the non-inverting pin is grounded because in normal operation both input pins
would be at 0V and the difference voltage between the positive supply and the input pins would be 800V. In this
kind of application, however, supply voltages +500V and -100V does meet the input common mode voltage range
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PA95U
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PA95
Product Innovation From
requirements since the maximum difference voltage between the inputs pins and the supply voltage is 500V (the
maximum allowed). The output has no such restrictions on its voltage swing. The output can swing within 24V of
either supply voltage regardless of value so long as the total supply voltage does not exceed 900V.
INPUT PROTECTION
Although the PA95 can withstand differential input voltages up to
±20V, additional external protection is recommended. In most applications 1N4148 or 1N914 signal diodes are sufficient (D1, D2 in
Figure 1a). In more demanding applications where low leakage or
low capacitance are of concern 2N4416 or 2N5457-2N5459 JFETs
connected as diodes will be required (Q1, Q2 in Figure 1b). In
either case the input differential voltage will be clamped to ±.7V.
This is sufficient overdrive to produce maximum power bandwidth.
Note that this protection does not automatically protect the amplifier from excessive common mode input voltages.
POWER SUPPLY PROTECTION
A.
+VS
Z1
–IN
D1
+IN
1
12
D2
PA95
2
10
+VS
Z2
Z1
–VS
B.
1
–IN
Q1
12
Q2
PA95
Unidirectional zener diode transient suppressors are recommend+IN
ed as protection on the supply pins. The zeners clamp transients
2
10
to voltages within the power supply rating and also clamp power
Z2
supply reversals to ground. Whether the zeners are used or not,
the system power supply should be evaluated for transient perfor–VS
mance including power-on overshoot and power-off polarity reverFIGURE 1. OVERVOLTAGE PROTECTION
sal as well as line regulation.
Conditions which can cause open circuits or polarity reversals on either power supply rail should be avoided or protected against. Reversals or opens on the negative supply rail is known to induce input stage failure. Unidirectional
transzorbs prevent this, and it is desirable that they be both electrically and physically as close to the amplifier as
possible.
STABILITY
The PA95 is stable at gains of 10 or more with a NPO (COG) compensation capacitor of 4.7pF. The compensation
capacitor, Cc, in the external connections diagram must be rated at 1000V working voltage and mounted closely to
pins 4 and 6 to prevent spurious oscillation. A compensation capacitor less than 4.7pF is not recommended.
EXTERNAL COMPONENTS
The compensation capacitor Cc must be rated for the total supply voltage. An NPO (COG)capacitor rated a 1kV is
recommended.
Of equal importance are the voltage rating and voltage coefficient of the gain setting feedback resistor. Typical voltage ratings of low wattage resistors are 150 to 250V. Up to 500 V can appear across the feedback resistor. High
voltage rated resistors can be obtained. However a 1 megohm feedback resistor composed of five 200k resistors in
series will produce the proper voltage rating.
CAUTIONS
The operating voltages of the PA95 are potentially lethal. During circuit design develop a functioning circuit at the
lowest possible voltages. Clip test leads should be used for "hands off" measurements while troubleshooting.
PA95U
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PA95
®
Product Innovation From
CONTACTING CIRRUS LOGIC SUPPORT
For all Apex Precision Power product questions and inquiries, call toll free 800-546-2739 in North America.
For inquiries via email, please contact [email protected]
International customers can also request support by contacting their local Cirrus Logic Sales Representative.
To find the one nearest to you, go to www.cirrus.com
IMPORTANT NOTICE
Cirrus Logic, Inc. and its subsidiaries ("Cirrus") believe that the information contained in this document is accurate and reliable. However, the information is subject
to change without notice and is provided "AS IS" without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus
for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third
parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights,
copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent
does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED TO BE
SUITABLE FOR USE IN PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER’S RISK AND CIRRUS DISCLAIMS AND MAKES NO WARRANTY, EXPRESS, STATUTORY OR IMPLIED, INCLUDING THE IMPLIED WARRANTIES OF
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Cirrus Logic, Cirrus, and the Cirrus Logic logo designs, Apex Precision Power, Apex and the Apex Precision Power logo designs are trademarks of Cirrus Logic, Inc.
All other brand and product names in this document may be trademarks or service marks of their respective owners.
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