APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
FEATURES
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
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 band-
width and slew rate for the application. APEX's Power SIP04
package uses a minimum of board space allowing for high
density circuit boards.
EQUIVALENT SCHEMATIC
TYPICAL APPLICATION
Piezo positioning may be applied to the focusing of seg-
mented mirror systems. The composite mirror may be com-
posed 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 increas-
ing circuit density with the SIP package.
H T T P : / / W W W . A P E X M I C R O T E C H . C O M ( 8 0 0 ) 5 4 6 - A P E X ( 8 0 0 ) 5 4 6 - 2 7 3 9
M I C R O T E C H N O L O G Y
HIGH VOLTAGE POWER OPERATIONAL AMPLIFIER
PA95
F
R
PA95
IN
R
PIEZO DRIVE
S
V
S
+V
OUT
V
COMPUTER
FOCUS
COMMAND
VOLTAGE
CL
R
1
2
10
8
7
12
EXTERNAL CONNECTIONS
PACKAGE SIP04
Q1
Q2
R1 R2
C1
12
R3
Q3
CC1
CC2
Q6
Q5
R5
R8
2
1
R9
Q15
R11
10
R12
Q16
Q12
Q8
R4
R7
7
8
6
4
Q4
ILIM
OUT
Q14
R10
Q13
Q11
+V
S
IN
+IN
V
S
R6
PHASE COMPENSATION
GAIN
C
C
10
4.7pF
R
LIM
=
.7
I
LIM
1
2
4
6
7
8
10
12
*
*
*
.01
F or greater ceramic power supply bypassing required.
IN
+IN
CC1
CC2 OUT I
lim
Vs
+Vs
C
c
R
LIM
PATENT PENDING
APEX MICROTECHNOLOGY CORPORATION 5980 NORTH SHANNON ROAD TUCSON, ARIZONA 85741 USA APPLICATIONS HOTLINE: 1 (800) 546-2739
ABSOLUTE MAXIMUM RATINGS
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
SUPPLY VOLTAGE, +V
S
to V
S
900V
OUTPUT CURRENT, source, sink
200mA, within SOA
POWER DISSIPATION, continuous @ T
C
= 25
C
30W
INPUT VOLTAGE, differential
20V
INPUT VOLTAGE, common mode
3
V
S
TEMPERATURE, pin solder - 10s max
220
C
TEMPERATURE, junction
2
150
C
TEMPERATURE, storage
65 to +150
C
OPERATING TEMPERATURE RANGE, case
55 to +125
C
PA95
SPECIFICATIONS
PARAMETER
TEST CONDITIONS
1
MIN
TYP
MAX
UNITS
INPUT
OFFSET VOLTAGE, initial
.5
5
mV
OFFSET VOLTAGE, vs. temperature
Full temperature range
15
50
V/
C
OFFSET VOLTAGE, vs. supply
10
25
V/V
OFFSET VOLTAGE, vs. time
75
V/
kh
BIAS CURRENT, initial
200
2000
pA
BIAS CURRENT, vs. supply
4
pA/V
OFFSET CURRENT, initial
50
500
pA
INPUT IMPEDANCE, DC
10
11
INPUT CAPACITANCE
4
pF
COMMON MODE VOLTAGE RANGE
3
Vs=
250V SEE NOTE 3
V
S
30
V
COMMON MODE REJECTION, DC
V
CM
=
90V
80
98
dB
NOISE
10KHz BW, R
S
= 1K
2
Vrms
GAIN
OPEN LOOP, @ 15Hz
R
L
= 5K
94
118
dB
GAIN BANDWIDTH PRODUCT at 1MHz R
L
= 5K
10
MHz
POWER BANDWIDTH
R
L
= 5K
20
kHz
PHASE MARGIN,Av=10
Full temperature range
60
OUTPUT
VOLTAGE SWING
I
O
= 100mA
V
S
24
V
S
20
V
CURRENT, continuous
100
mA
SLEW RATE, A
V
= 100
C
C
=4.7pF
30
V/
s
SETTLING TIME to .1%
2V step
1
s
RESISTANCE
no load
100
POWER SUPPLY
VOLTAGE
5
See note 5
50
300
450
V
CURRENT, quiescent
1.6
2.2
mA
THERMAL
RESISTANCE, AC, junction to case
4
Full temperature range, F > 60Hz
2.5
C/W
RESISTANCE, DC, junction to case
Full temperature range, F < 60Hz
4.2
C/W
RESISTANCE, junction to air
Full temperature range
30
C/W
TEMPERATURE RANGE, case
25
+85
C
NOTES: 1.
Unless otherwise noted: T
C
= 25
C, DC input specifications are
value given. Power supply voltage is typical rating. C
c
= 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.
CAUTION
The PA95 is constructed from MOSFET transistors. ESD handling procedures must be observed.
APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
TYPICAL PERFORMANCE
GRAPHS
PA95
0
25
50
75
100
125
150
TEMPERATURE, T (
C)
0
5
15
20
POWER DERATING
INTERNAL POWER DISSIPATION, P(W)
10
100
10K
1M
FREQUENCY, F (Hz)
0
100
OUTPUT CURRENT, I (mA)
4
8
16
24
OUTPUT VOLTAGE SWING
12
20
3
10
20
100
CURRENT LIMIT RESISTOR, R
CL
( )
10
30
200
CURRENT LIMIT
CURRENT LIMIT, I (mA)
LIM
50
70
5
50
20
INPUT NOISE
1K
2
7
10
20
3
5
15
O
20
VOLTAGE DROP FROM SUPPLY, V
V (V)
SO
10
30
60
25
40
120
100
150
T = 25
C
C
T = 55
C
C
T = 125
C
C
T = 85
C
C
80
T = T
C
T = T
A
SAFE OPERATING AREA
SUPPLY TO OUTPUT DIFFERENTIAL, VS VO (V)
50
50
OUTPUT CURRENT FROM +V
S
OR
V
S
, (mA)
5
10
15
25
DC, T
C
= 125
C
DC, T
C
= 85
C
200mS
PULSE CURVES @ 10% DUTY CYCLE MAX
DC, T
C
= 25
C
100mS
100
100
150
200
250
500
1K
1M
2M
3M
4M 5M
FREQUENCY, F (Hz)
-90
-135
-180
-225
-270
-315
-360
PHASE RESPONSE
PHASE,
(
)
C = 4.7pF
100K
300K
FREQUENCY, F (Hz)
50
1K
500
POWER RESPONSE
OUTPUT VOLTAGE, V (V )
O
P-P
100
10K
C = 4.7pF
C
200
0
200
600
800
1000
TOTAL SUPPLY VOLTAGE, V (V)
1.08
1.04
1.00
.96
.92
.88
QUIESCENT CURRENT
QUIESCENT CURRENT, I(X)
S
400
FREQUENCY, F (Hz)
SMALL SIGNAL RESPONSE
OPEN LOOP GAIN, A (dB)
0
60
120
20
40
80
100
100
1K 10K 100K 1M 10M
10
C = 4.7pF
C
INPUT NOISE VOLTAGE, V
N
(nV/
Hz)
OPERATING
CONSIDERATIONS
PA95
GENERAL
Please read the "General Operating Considerations" sec-
tion, which covers stability, supplies, heatsinking, mounting,
current limit, SOA interpretation, and specification interpreta-
tion. 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.
CURRENT LIMIT
For proper operation, the current limit resistor (R
LIM
) 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
R
LIM
=
I
LIM
COMMON MODE INPUT RANGE
Operational amplifiers are usually designed to have a com-
mon 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 re-
stricted. 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 volt-
ages 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 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 suffi-
cient (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 re-
quired (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
Unidirectional zener diode transient suppressors are recom-
mended as protection on the supply pins. The zeners clamp
transients to voltages within the power supply rating and also
clamp power supply reversals to ground. Whether the zeners
are used or not, the system power supply should be evaluated
for transient performance including power-on overshoot and
power-off polarity reversal as well as line regulation.
Conditions which can cause open circuits or polarity rever-
sals 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 capaci-
tor, 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 recom-
mended.
Of equal importance are the voltage rating and voltage
coefficient of the gain setting feedback resistor. Typical volt-
age 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 feed-
back 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.
FIGURE 1. OVERVOLTAGE PROTECTION
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.
PA95U REV. B DECEMBER 1999
1999 Apex Microtechnology Corp.
PA95
+V
S
IN
+IN
Z1
Z2
D2
D1
12
10
1
2
+V
S
IN
+IN
Z1
Z2
12
10
1
2
PA95
Q1
Q2
A.
B.
V
S
V
S
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