ultra-accurate/high slew rate inverting operational amplifier

MIL-PRF-38534 CERTIFIED
M.S.KENNEDY CORP.
ULTRA-ACCURATE/HIGH SLEW RATE
INVERTING
OPERATIONAL AMPLIFIER
4707 Dey Road Liverpool, N.Y. 13088
739
(315) 701-6751
FEATURES:
Very Fast Setting Time - 10nS to 0.1% Typical
Very Fast Slew Rate - 5500 V/µS Typical
Unity Gain Bandwidth - 220 MHz Typical
Low Noise - 0.15uVrms Typical (f=0.1Hz to 10Hz)
Very Accurate (Low Offset) ±75µV Max.
Pin Compatable with AD9610
Contact MSK for MIL-PRF-38534 Qualification Status
DESCRIPTION:
The MSK 739 is an inverting composite operational amplifier that combines extremely high bandwidth and slew rate with
excellent D.C. accuracy to produce an amplifier perfectly suited for high performance data aquisition and conversion as well
as high speed commmunication and line drive. The performance of the MSK 739 is guaranteed over the full military temperature range and for more cost sensitive applications is available in an industrial version. The standard package style is a
space efficient 12 pin TO-8. However, alternate package styles are available upon request.
EQUIVALENT SCHEMATIC
EQUIVALENT
SCHEMATIC
TYPICAL APPLICATIONS
TYPICAL APPLICATIONS
PIN-OUT INFORMATION
1
2
3
4
5
6
High Performance Data Aquisition
Coaxial Line Driver
Data Conversion Circuits
High Speed Communications
Ultra High Resolution Video Amplifier
1
Positive Power Supply 7 Ground
8 NC
NC
9 Negative Power Supply
Case Ground
10 Negative Short Circuit
Internal Feedback
11 Output
Inverting Input
12 Positive Short Circuit
Non-Inverting Input
Rev. B 9/06
8
ABSOLUTE MAXIMUM RATINGS
±VCC
IOUT
VIN
RTH
Supply Voltage
Peak Output Current
Differential Input Voltage
Thermal Resistance
Junction to Case
Output Devices Only
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
+18V
±200mA
±12V
46°C/W
○
○
○
○
○
○
-65°C to +150°C
TST Storage Temperature Range
300°C
TLD Lead Temperature Range
(10 Seconds Soldering)
See Curve
PD Power Dissipation
150°C
TJ Junction Temperature
TC Case Operating Temperature Range
(MSK739B/E)
-55°C to+125°C
(MSK739)
-25°C to +85°C
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
ELECTRICAL SPECIFICATIONS
±Vcc=±15V Unless Otherwise Specified
Group A
Test Conditions
Parameter
MSK 739B/E
Subgroup Min.
MSK 739
Typ.
Max.
Min.
Typ.
Max.
Units
STATIC
Supply Voltage Range 2
Quiescent Current
Thermal Resistance 2
-
±12
±15
±18
±12
±15
±18
V
Vin=0V
1
-
±35
±37
-
±37
±40
mA
Av=-1V/V
2,3
-
±36
±39
-
-
-
mA
Output Devices Junction to Case
-
-
45
-
-
48
-
°C/W
Vin=0V Av=-100V/V
1
-
±25
±75
-
±50
±100
µV
Vin=0V
2,3
-
±0.5
±1.5
-
±0.75
±2.0 µV/°C
Vcm=0V
1
-
±10
±40
-
±20
±60
nA
Either Input
2,3
-
±15
±80
-
-
-
nA
INPUT
Input Offset Voltage
Input Offset Voltage Drift
Input Bias Current 7
Input Offset Current
1
-
5
20
-
10
30
nA
2,3
-
5
40
-
-
-
nA
F=DC Differential
-
-
5
-
-
5
-
MΩ
∆Vcc=±5V
-
-
1
8
-
2
20
µV/V
Vcm=0V
Input Impedance 2
Power Supply Rejection Ratio 2
2
Input Noise Voltage
F= 0.1Hz To 10Hz
-
-
0.15
-
-
0.2
-
µVp-p
Input Noise Voltage Density
2
F=1KHz
-
-
3.8
-
-
4
-
nV√Hz
Input Noise Current Density
2
F=1KHz
-
-
0.6
-
-
0.7
-
pA√Hz
RL=100Ω Av=-3V/V F≤10MHz
4
±10
±12.5
-
±10
±12.5
-
V
TJ <150°C
4
±100 ±120
-
±100 ±120
-
mA
0.1% 10V step RL=1KΩ
-
-
10
35
-
15
45
nS
RL=100Ω Vo=±10V
4
20
22
-
15
20
-
MHz
RL=100Ω
-
175
220
-
165
190
-
MHz
VOUT=±10V RL=1KΩ Av= -1.5V/V
4
4000
5500
-
3500
4000
-
V/µS
RL=1KΩ F=1KHz VOUT=±10V
4
100
110
-
95
105
-
dB
OUTPUT
Output Voltage Swing
Output Current
Settling Time
1
2
Full Power Bandwidth
Bandwidth (Small Signal)
2
TRANSFER CHARACTERISTICS
Slew Rate
Open Loop Voltage Gain
2
NOTES:
1
2
3
4
5
6
AV= -1, measured in false summing junction circuit.
Guaranteed by design but not tested. Typical parameters are representative of actual device performance but are for reference only.
Industrial grade and "E" suffix devices shall be tested to subgroups 1 and 4 unless otherwise specified.
Military grade devices ("B" suffix) shall be 100% tested to subgroups 1,2,3 and 4.
Subgroups 5 and 6 testing available upon request.
TA=TC=+25°C
Subgroup 1,4
TA=TC=+125°C
Subgroup 2
TA=TC=-55°C
Subgroup 3
7 Measurement taken 0.5 seconds after application of power using automatic test equipment.
8 Continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle.
2
Rev. B 9/06
APPLICATION NOTES
HEAT SINKING
The value of the short circuit current limit resistors (±RSC) can
be calculated as follows.
To determine if a heat sink is necessary for your application and
if so, what type, refer to the thermal model and governing equation
below.
-RSC=VCC+0.7/-ISC
+RSC=VCC-0.7/+ISC
Thermal Model:
Short circuit current limit should be set at least 2X above the
highest normal operating output current to keep the value of RSC low
enough to ensure that the voltage dropped accross the short circuit
current limit resistor doesn't adversely affect normal operation.
INTERNAL FEEDBACK RESISTOR
The MSK 739 is equipped with an internal 1.5KΩ feedback resistor. Bandwidth and slew rate can be optimized by connecting the
MSK 739 as shown in Figure 2. Placing the feedback resistor inside
the hybrid reduces printed circuit board trace length and its'
asscociated capacitance which acts as a capacitive load to the opamp output. Reducing the capacitive load allows the output to slew
faster and greater bandwidths will be realized. Refer to Table 1 for
recommended RIN values for various gains.
Governing Equation:
TJ=PD x (RθJC + RθCS + RθJC) + TA
Where
TJ=Junction Temperature
PD=Total Power Dissipation
RθJC=Junction to Case Thermal Resistance
RθCS=Case to Heat Sink Thermal Resistance
RθSA=Heat Sink to Ambient Thermal Resistance
TC=Case Temperature
TA=Ambient Temperature
TS=Sink Temperature
Example:
This example demonstrates a worst case analysis for the op-amp
output stage. This occurs when the output voltage is 1/2 the power
supply voltage. Under this condition, maximum power transfer occurs and the output is under maximum stress.
Conditions:
V CC=±16VDC
VO=±8Vp Sine Wave, Freq.=1KHz
R L=100Ω
TABLE 1
RIN
VALUE
1.5KΩ
750Ω
150Ω
Whenever the internal resistor is not being used it is good practice
to short pin 4 and 5 to avoid inadvertently picking up spurious signals.
For a worst case analysis we will treat the +8Vp sine wave
as an 8VDC output voltage.
1.) Find Driver Power Dissapation
PD=(VCC-VO) (VO/RL)
=(16V-8V) (8V/100Ω)
=0.64W
2.) For conservative design, set TJ=+125°C
3.) For this example, worst case TA=+90°C
4.) RθJC=45°C/W from MSK 739B Data Sheet
5.) RθCS=0.15°C/W for most thermal greases
6.) Rearrange governing equation to solve for RθSA
APPROXIMATE
DESIRED GAIN
-1
-2
-10
Recommended External Component Selection
Guide Using External Rf
TABLE 2
APPROXIMATE
DESIRED GAIN
1
1
1
1
1
1
RθSA=((TJ-TA)/PD) - (RθJC) - (RθCS)
=((125°C -90°C)/0.64W) - 45°C/W - 0.15°C/W
=54.7 - 46.15
=9.5°C/W
-1
-2
-5
-8
-10
-20
RI(+)
249Ω
160Ω
169Ω
100Ω
90.9Ω
100Ω
RI(-)
Rf(Ext)
Cf
499Ω
249Ω
200Ω
124Ω
100Ω
100Ω
499Ω
499Ω
1KΩ
1KΩ
1KΩ
2KΩ
2
2
2
2
2
2
OUTPUT SHORT CIRCUIT PROTECTION
The output section of the MSK 739 can be protected from direct
shorts to ground by placing current limit resistors between pins 1
and 12 and pins 9 and 10 as shown in Figure 1.
1 The positive input resistor is selected to minimize any bias current induced offset
voltage.
2 The feedback capacitor will help compensate for stray input capacitance. The value of
this capacitor can be dependent on individual applications. A 0.5 to 5pF capacitor is
usually optimum for most applications.
3 Effective load is RL in parallel with Rf.
3
Rev. B 9/06
APPLICATION NOTES CON'T
STABILITY AND LAYOUT CONSIDERATIONS
OPTIMIZING SLEW RATE
As with all wideband devices, proper decoupling of the power
lines is extremely important. The power supplies should be by-passed
as near to pins 9 and 1 as possible with a parallel grouping of a
0.01µf ceramic disc and a 4.7µf tantalum capacitor. Wideband devices are also sensitive to printed cicuit board layout. Be sure to
keep all runs as short as possible, especially those associated with
the summing junction and power lines. Circuit traces should be surrounded by ground planes whenever possible to reduce unwanted
resistance and inductance. The curve below shows the relationship
between resonant frequency and capacitor value for 3 trace lengths.
When measuring the slew rate of the MSK 739, many external
factors must be taken into consideration to achieve best results. The
closed loop gain of the test fixture should be -1.5V/V or less with
the external feedback resistor being 499Ω Lead length on this resistor must be as short as possible and the resistor should be small. No
short circuit current limit resistors should be used. (Short pin 1 to
pin 12 and pin 9 to pin 10). Pins 2,3,7 and 8 should all be shorted
directly to ground for optimum response. Since the internal feedback
resistor isn't being used, pin 4 should be shorted to pin 5. SMA
connectors are recomended for the input and output connectors to
keep external capacitances to a minimum. To compensate for input
capacitance, a small 0.5 to 5pF high frequency variable capacitor
should be connected in parallel with the feedback resistor. This capacitor will be adjusted to trim overshoot to a minimum. A 5500V/
µS slew rate limit from -10V to +10V translates to a transition time
of 2.9 nanoseconds. In order to obtain a transition time of that magnitude at the output of the test fixture, the transition time of the
input must be much smaller. A rise time at the input of 500 picoseconds or less is sufficient. If the transition time of the input is greater
than 500 picoseconds, the following formula should be used, since
the input transition time is now affecting the measured system transition time.
TA=√TB²+ TC²
WHERE:
TA=Transition time measured at output jack on MSK 739 test card.
TB=Transition time measured at input jack on MSK 739 test card.
TC=Actual output transition time of MSK 739(note that this quantity
will be calculated, not measured directly with the oscilloscope).
FEEDBACK CAPACITANCE
THE MSK 739 IS INVERTING, THEREFORE WHEN MEASURING RISING EDGE SLEW RATE:
Feedback capacitance is commonly used to compensate for the
"input capacitance" effects of amplifiers. Overshoot and ringing,
especially with capacitive loads, can be reduced or eliminated with
the proper value of feedback capacitance.
All capacitors have a self-resonant frequency. As capacitance increases, self-resonant frequency decreases (assuming all other factors remain the same). Longer lead lengths and PC traces are other
factors that tend to decrease the self-resonant frequency. When a
feedback capacitor's self-resonant frequency falls within the frequency band for which the amplifier under consideration has gain,
oscillation occurs. These influences place a practical upper limit on
the value of feedback capacitance that can be used. This value is
typically 0.5 to 5pF for the MSK 739(B).
TA=Rise time measured at output
TB=Fall time measured at input
TC=Actual rise time of output
WHEN MEASURING FALLING EDGE SLEW RATE:
TA=Fall time measured at output
TB=Rise time measured at input
TC=Actual fall time of output
LOAD CONSIDERATIONS
When determining the load an amplifier will see, the capacitive
portion must be taken into consideration. For an amplifier that slews
at 1000V/µS, each pF will require 1mA of output current.
To minimize ringing with highly capacitive loads, reduce the load
time constant by adding shunt resistance.
I=C(dV/dT)
CASE CONNECTION
The MSK 739(B) has pin 3 internally connected to the case. The
case is not electrically connected to the internal circuit. Pin 3 should
be tied to a ground plane for sheilding. For special applications,
consult factory.
4
Rev. B 9/06
TYPICAL PERFORMANCE CURVES
5
Rev. B 9/06
MECHANICAL SPECIFICATIONS
NOTE:Standard cover height:
MSK 739 0.200 Max.
Alternate lid heights available
WEIGHT=3 GRAMS TYPICAL
NOTE: ALL DIMENSIONS ARE ±0.010 INCHES UNLESS OTHERWISE LABELED.
ORDERING INFORMATION
MSK739 B
SCREENING
BLANK=INDUSTRIAL; B=MIL-PRF-38534 CLASS H
E=EXTENDED RELIABILITY
GENERAL PART NUMBER
M.S. Kennedy Corp.
4707 Dey Road, Liverpool, New York 13088
Phone (315) 701-6751
FAX (315) 701-6752
www.mskennedy.com
The information contained herein is believed to be accurate at the time of printing. MSK reserves the right to make
changes to its products or specifications without notice, however, and assumes no liability for the use of its products.
Please visit our website for the most recent revision of this datasheet.
Contact MSK for MIL-PRF-38534 qualification status.
6
Rev. B 9/06