APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
FEATURES
VERY FAST SLEW RATE -- 900 V/
s
POWER MOS TECHNOLOGY -- 4A peak rating
LOW INTERNAL LOSSES -- 2V at 2A
PROTECTED OUTPUT STAGE -- Thermal Shutoff
WIDE SUPPLY RANGE --
15V TO
40V
APPLICATIONS
VIDEO DISTRIBUTION AND AMPLIFICATION
HIGH SPEED DEFLECTION CIRCUITS
POWER TRANSDUCERS UP TO 5 MHz
MODULATION OF RF POWER STAGES
POWER LED OR LASER DIODE EXCITATION
DESCRIPTION
The PA19 is a high voltage, high current operational ampli-
fier optimized to drive a variety of loads from DC through the
video frequency range. Excellent input accuracy is achieved
with a dual monolithic FET input transistor which is cascoded
by two high voltage transistors to provide outstanding com-
mon mode characteristics. All internal current and voltage
levels are referenced to a zener diode biased on by a current
source. As a result, the PA19 exhibits superior DC and AC
stability over a wide supply and temperature range.
High speed and freedom from second breakdown is as-
sured by a complementary power MOS output stage. For
optimum linearity, especially at low levels, the power MOS
transistors are biased in a class A/B mode. Thermal shutoff
provides full protection against overheating and limits the
heatsink requirements to dissipate the internal power losses
under normal operating conditions. A built-in current limit of
0.5A can be increased with the addition of two external
resistors. Transient inductive load kickback protection is pro-
vided by two internal clamping diodes. External phase com-
pensation allows the user maximum flexibility in obtaining the
optimum slew rate and gain bandwidth product at all gain
settings. A heatsink of proper rating is recommended.
This hybrid circuit utilizes thick film (cermet) resistors,
ceramic capacitors, and silicon semiconductor chips to maxi-
mize reliability, minimize size, and give top performance.
Ultrasonically bonded aluminum wires provide reliable inter-
connections at all operating temperatures. The 8-pin TO-3
package is hermetically sealed and electrically isolated. The
use of compressible thermal washers and/or improper mount-
ing torque will void the product warranty. Please see "General
Operating Considerations".
TOP
VIEW
1
2
3
4
5
6
7
8
V
+IN
IN
OUT
C
C
R
CL
PHASE COMPENSATION
C
C
330pF
22pF
2.2pF
none
GAIN
1
10
100
1000
+V
R
CL+
TYPICAL APPLICATION
This fast power driver utilizes the 900V/
s slew rate of the
PA19 and provides a unique interface with a current output
DAC. By using the DAC's internal 1K
feedback resistor,
temperature drift errors are minimized, since the temperature
drift coefficients of the internal current source and the internal
feedback resistor of the DAC are closely matched. Gain of
V
OUT
to I
IN
is 6.5/mA. The DAC's internal 1K resistor together
with the external 500
and 110
form a "tee network" in the
feedback path around the PA19. This effective resistance
equals 6.5K
. Therefore the entire circuit can be modeled as
6.5K
feedback resistor from output to inverting input and a
5mA current source into the inverting input of the PA19. Now
we see the familiar current to voltage conversion for a DAC
where V
OUT
= I
IN
x R
FEEDBACK
.
EQUIVALENT SCHEMATIC
EXTERNAL CONNECTIONS
3
6
8
5
4
1
Q3
Q5
Q4
D1
D2
Q16
Q13
Q12
Q1
Q7
Q19
Q17B
Q11
Q10
2
7
Q15
Q20
Q24
Q25
Q21
Q22
Q9
Q8
Q2
Q17A
Q23
+40V
40V
32.5V
R
CL+
PA19
PA19 AS FAST POWER DRIVER
R
CL
5.6pF
Up to 4A
110
500
5mA
1K
DAC
TYPICAL
APPLICATION
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
VIDEO POWER OPERATIONAL AMPLIFIERS
PA19 PA19A
APEX MICROTECHNOLOGY CORPORATION 5980 NORTH SHANNON ROAD TUCSON, ARIZONA 85741 USA APPLICATIONS HOTLINE: 1 (800) 546-2739
ABSOLUTE MAXIMUM RATINGS
SPECIFICATIONS
SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
SUPPLY VOLTAGE, +V
S
to V
S
80V
OUTPUT CURRENT, within SOA
5A
POWER DISSIPATION, internal
78W
INPUT VOLTAGE, differential
40V
INPUT VOLTAGE, common mode
V
S
TEMPERATURE, pin solder -- 10 sec
300
C
TEMPERATURE, junction
1
150
C
TEMPERATURE, storage
65 to 155
C
OPERATING TEMPERATURE RANGE, case
55 to 125
C
PARAMETER
TEST CONDITIONS
2
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
INPUT
OFFSET VOLTAGE, initial
T
C
= 25
C
.5
3
.25
.5
mV
OFFSET VOLTAGE, vs. temperature
T
C
= 25
C to +85
C
10
30
5
10
V/
C
OFFSET VOLTAGE, vs. supply
T
C
= 25
C
10
*
V/V
OFFSET VOLTAGE, vs. power
T
C
= 25
C to +85
C
20
*
V/W
BIAS CURRENT, initial
T
C
= 25
C
10
200
5
50
pA
BIAS CURRENT, vs. supply
T
C
= 25
C
.01
*
pA/V
OFFSET CURRENT, initial
T
C
= 25
C
5
100
3
25
pA
INPUT IMPEDANCE, DC
T
C
= 25
C
10
11
*
M
INPUT CAPACITANCE
T
C
= 25
C
6
*
pF
COMMON MODE VOLTAGE RANGE
3
T
C
= 25
C to +85
C
V
S
15
V
S
12
*
*
V
COMMON MODE REJECTION, DC
T
C
= 25
C to +85
C, V
CM
=
20V
70
104
*
*
dB
GAIN
OPEN LOOP GAIN at 10Hz
T
C
= 25
C, R
L
= 1K
111
*
dB
OPEN LOOP GAIN at 10Hz
T
C
= 25
C, R
L
= 15
74
78
*
*
dB
GAIN BANDWIDTH PRODUCT at 1MHz T
C
= 25
C, C
C
= 2.2pF
100
*
MHz
POWER BANDWIDTH, A
V
= 100
T
C
= 25
C, C
C
= 2.2pF
3.5
*
MHz
POWER BANDWIDTH, A
V
= 1
T
C
= 25
C, C
C
= 330pF
250
*
kHz
OUTPUT
VOLTAGE SWING
3
T
C
= 25
C, I
O
= 4A
V
S
5
V
S
4
*
*
V
VOLTAGE SWING
3
T
C
= 25
C to +85
C, I
O
= 2A
V
S
3
V
S
2
*
*
V
VOLTAGE SWING
3
T
C
= 25
C to +85
C, I
O
= 78mA
V
S
1
V
S
.5
*
*
V
SETTLING TIME to .1%
T
C
= 25
C, 2V step
.3
*
s
SETTLING TIME to .01%
T
C
= 25
C, 2V step
1.2
*
s
SLEW RATE, A
V
= 100
T
C
= 25
C, C
C
= 2.2pF
600
900
800
*
V/
s
SLEW RATE, A
V
= 10
T
C
= 25
C, C
C
= 22pF
650
*
V/
s
POWER SUPPLY
VOLTAGE
T
C
= 25
C to +85
C
15
35
40
*
*
*
V
CURRENT, quiescent
T
C
= 25
C
100
120
*
*
mA
THERMAL
RESISTANCE, AC, junction to case
4
T
C
= 25
C to +85
C, F > 60Hz
1.2
1.3
*
*
C/W
RESISTANCE, DC, junction to case
T
C
= 25
C to +85
C, F < 60Hz
1.6
1.8
*
*
C/W
RESISTANCE, junction to air
T
C
= 25
C to +85
C
30
*
C/W
TEMPERATURE RANGE, case
Meets full range specifications
25
+85
*
*
C
PA19A
PA19
PA19 PA19A
NOTES:
*
The specification of PA19A is identical to the specification for PA19 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.
+V
S
and V
S
denote the positive and negative supply rail respectively. Total V
S
is measured from +V
S
to V
S
.
4.
Rating applies if the output current alternates between both output transistors at a rate faster than 60Hz.
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.
CAUTION
APEX MICROTECHNOLOGY CORPORATION TELEPHONE (520) 690-8600 FAX (520) 888-3329 ORDERS (520) 690-8601 EMAIL prodlit@apexmicrotech.com
TYPICAL PERFORMANCE
GRAPHS
PA19 PA19A
0
25
50
75
100
125
CASE TEMPERATURE, T
C
(
C)
10
40
60
80
POWER DERATING
INTERNAL POWER DISSIPATION, P(W)
50
100
1.0
3.0
3.5
CURRENT LIMIT
2.0
.5
10
100
10K
1M
FREQUENCY, F (Hz)
INPUT NOISE VOLTAGE, V
N
(nV/ Hz)
100
100M
FREQUENCY, F (Hz)
20
0
60
SMALL SIGNAL RESPONSE
OPEN LOOP GAIN, A
OL
(dB)
20
40
80
100
0
2V
OUTPUT VOLTAGE SWING
4V
FREQUENCY, F (Hz)
OUTPUT VOLTAGE, V (V )
O
COMPENSATION CAPACITOR, C
C
(pF)
SLEW RATE VS. COMP.
SLEW RATE, (V/
s)
200
TIME, t (ns)
30
20
30
PULSE RESPONSE
OUTPUT VOLTAGE, V
O
(V)
10
20
10
COMMON MODE VOLTAGE
COMMON MODE VOLTAGE, V
CM
(V
PP
)
1K
10M
FREQUENCY, F (Hz)
COMMON MODE REJECTION
COMMOM MODE REJECTION, CMR (dB)
40
80
120
10K
100K
1K
FREQUENCY, F (Hz)
POWER SUPPLY REJECTION
POWER SUPPLY REJECTION, PSR (dB)
30
60
80
TOTAL SUPPLY VOLTAGE, V
S
(V)
1.4
QUIESCENT CURRENT
CURRENT LIMIT, I
LIM
(A)
1.2
45
INPUT NOISE
1K
10
15
20
25
25
50
75
2.5
50
POWER RESPONSE
PP
50 0
50 100 150
10
40
50
70
.6
.8
1K
100K
150
70
OUTPUT CURRENT, I
O
(A)
VOLTAGE DROP FROM SUPPLY (V)
NORMALIZED QUIESCENT CURRENT, I
Q
(X)
1.0
1M
20
60
100
10K
100K
1M
100M
0
20
40
60
80
100
0
1.5
1.6
CASE TEMPERATURE, T
C
(
C)
1V
3V
30
100
1K
10K 100K
1M
50
55
60
65
70
0
100M
0
125
1
2
3
4
10M
7
5
3
100K
40
250 300
30
20
0
10K
1M
10M
5
10M
10
100
400
2
4
20
40
200
40
100
200
600
400
1000
800
6
60
80
21
30
41
58
15
1M
20M
100K 200K
2M
4M 8M
600K
80
11
8
C
C
= 2.2pF
C
C
= 22pF
C
C
= 330pF
| +V
S
| + | V
S
| = 80V
R
L
= 15
+V
V
2.2pF
22pF
330pF
R
L
= 15
R
L
= 15
V
IN
=
2V
A
V
= 10
t
r
= 10ns
R
CL
= 0.27
R
CL
= 1.2
R
CL
=
FREQUENCY, F (Hz)
APEX MICROTECHNOLOGY CORPORATION 5980 NORTH SHANNON ROAD TUCSON, ARIZONA 85741 USA APPLICATIONS HOTLINE: 1 (800) 546-2739
OPERATING
CONSIDERATIONS
PA19 PA19A
2. Safe short circuit combinations of voltage and current are limited to
a power level of 100W.
3. The output stage is protected against transient flyback. However,
for protection against sustained, high energy flyback, external fast-
recovery diodes should be used.
SUPPLY CURRENT
The PA19 features a class A/B driver stage to charge and discharge
gate capacitance of Q7 and Q19. As these currents approach 0.5A, the
savings of quiescent current over that of a class A driver stage is
considerable. However, supply current drawn by the PA19, even with
no load, varies with slew rate of the output signal as shown below.
OUTPUT LEADS
Keep the output leads as short as possible. In the video frequency
range, even a few inches of wire have significant inductances, raising
the interconnection impedance and limiting the output current slew
rate. Furthermore, the skin effect increases the resistance of heavy
wires at high frequencies. Multistrand Litz Wire is recommended to
carry large video currents with low losses.
THERMAL SHUTDOWN
The thermal protection circuit shuts off the amplifier when the
substrate temperature exceeds approximately 150
C. This allows the
heatsink selection to be based on normal operating conditions while
protecting the amplifier against excessive junction temperature during
temporary fault conditions.
Thermal protection is a fairly slow-acting circuit and therefore does
not protect the amplifier against transient SOA violations (areas
outside of the steady state boundary). It is designed to protect against
short-term fault conditions that result in high power dissipation within
the amplifier. If the conditions that cause thermal shutdown are not
removed, the amplifier will oscillate in and out of shutdown. This will
result in high peak power stresses, destroy signal integrity, and reduce
the reliability of the device.
STABILITY
Due to its large bandwidth, the PA19 is more likely to oscillate than
lower bandwidth power operational amplifiers. To prevent oscillations
a reasonable phrase margin must be maintained by:
1. Selection of the proper phase compensation capacitor. Use the
values given in the table under external connections and interpo-
late if necessary. The phase margin can be increased by using a
larger capacitor at the expense of slew rate. Total physical length
(pins of the PA19, capacitor leads plus printed circuit traces) should
be limited to a maximum of 3.5 inches.
2. Keep the external sumpoint stray capacitance to ground at a
minimum and the sumpoint load resistance (input and feedback
resistors in parallel) below 500
. Larger sumpoint load resistances
can be used with increased phase compensation and/or by bypass-
ing the feedback resistor.
3. Connect the case to any AC ground potential.
I
LIM
= +.54A
.65V
R
CL
R
CL
=
.65V
I
CL
.54A
GENERAL
Please read the "General Operating Considerations" section, 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.
CURRENT LIMIT
Q2 (and Q25) limit output current by turning on and removing gate
drive when voltage on pin 2 (pin 7) exceeds .65V differential from the
positive (negative) supply rail. With internal resistors equal to 1.2
,
current limits are approximately 0.5A with no external current limit
resistors. With the addition of external resistors current limit will be:
To determine values of external current limit resistors:
PHASE COMPENSATION
At low gain settings, an external compensation capacitor is required
to insure stability. In addition to the resistive feedback network, roll off
or integrating capacitors must also be considered when determining
gain settings. The capacitance values listed in the external connection
diagram, along with good high frequency layout practice, will insure
stability. Interpolate values for intermediate gain settings.
SAFE OPERATING AREA (SOA)
The MOSFET output stage of this power operational amplifier has
two distinct limitations:
1. The current handling capability of the MOSFET geometry and the
wire bonds.
2. The junction temperature of the output MOSFETs.
The SOA curves combine the effect of these limits and allow for
internal thermal delays. 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:
1. Capacitive and inductive loads up to the following maximums are
safe:
V
S
CAPACITIVE LOAD
INDUCTIVE LOAD
40V
.1
F
11mH
30V
500
F
24mH
20V
2500
F
75mH
15V
100mH
2.0
3.0
4.0
5.0
1.5
2.5
3.5
30
50
20
40
25
15
35
70
60
80
OUTPUT CURRENT FROM V
S
OR V
S
(A)
INTERNAL VOLTAGE DROP SUPPLY TO OUTPUT V
S
V
O
(V)
STEADY STATE
t = 300ms
t = 100ms
T
C
= 25C
SUPPLY CURRENT
400
300
200
100
0
30K 100K 300K
1M
3M 10M
FREQUENCY, F (Hz)
SUPPLY CURRENT, I
S
(mA)
V
OUT
= 60V
PP
SINE
R
L
= 500
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.
PA19U REV. H FEBRUARY 1998
1998 Apex Microtechnology Corp.
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