MIL-PRF-38534 AND 38535 CERTIFIED FACILITY
RAD HARD
NEGATIVE, 3 AMP,
LOW DROPOUT
VOLTAGE REGULATOR
5940RH
SERIES
FEATURES:
•
•
•
•
•
•
•
•
•
•
•
•
Manufactured using
Space Qualified RH1185 Die
Radiation Hardened to 100 Krads(Si)(Method 1019.7 Condition A)
-5V, -5.2V, -10V, -12V and -15V Standard Versions
Low Dropout Voltage
Output Current to 3 Amps
Output Voltage Internally Set to ±1% MAX.
Internal Short Circuit Current Limit
Internal Thermal Overload Protection
Lead Form Options: Straight, Up and Down
Alternate Output Voltages Available
Available with Top Tab or Tabless Package
Equivalent Non Rad Device MSK 5332
DESCRIPTION:
The MSK 5940RH is a fixed, radiation hardened, negative voltage regulator which offers low dropout and output voltage
accuracy to ±1% maximum. The low θjc combined with low dropout allows increased output current and excellent device
efficiency. The MSK 5940RH offers both internal current limit and thermal overload protection. The case of the device
is electrically isolated for heat sinking purposes. The device is packaged in a space efficient 3 pin power package with
various lead form options. The MSK 5940RH series is also available in a power package with a top tab to accomodate direct
mounting to a heat sink.
EQUIVALENT SCHEMATIC
PIN-OUT INFORMATION
TYPICAL APPLICATIONS
•
•
•
•
High Efficiency Linear Regulators
Constant Voltage/Current Regulators
System Power Supplies
Switching Power Supply Post Regulators
1
2
3
GND
VIN
VOUT
CASE = ISOLATED
1
8548-56 Rev. K 2/18
ABSOLUTE MAXIMUM RATINGS
-VIN
-VIN
PD
IOUT
TJ
IOUT
9
Input Voltage..................................................... -35V
Input Voltage (WRT VOUT)................................. -30V
Power Dissipation......................... Internally Limited
Output Current.................................................... -3A
Junction Temperature.................................. +150°C
Output Reverse Voltage..................................... -2V
TST Storage Temperature Range......... -65°C to +150°C
TLD Lead Temperature Range.............................. 300°C
(10 Seconds)
Case Operating Temperature
MSK 5940K/H RH........................ -55°C to +125°C
MSK 5940RH................................. -40°C to +85°C
TC
ELECTRICAL SPECIFICATIONS
Parameter
Test Conditions
Output Voltage Tolerance
3
10
Typ.
Max.
Min.
Typ.
Max.
Iout = 10mA; Vin = Vout +3V
0A ≤ Iout ≤ 3A; δVout = 1%
2
Post Radiation
Load Regulation
10mA ≤ Iout ≤ 3A
Vin = Vout + 3V
Line Regulation
Iout = 10mA
(Vout +3V) ≤ Vin ≤ (Vout + 15V)
Post Radiation
Post Radiation
Quiescent Current
Vin = Vout +3V; Iout = 10mA
Short Circuit Current
Ripple Rejection
2
2
Thermal Resistance
2
MSK 5940RH
Min.
Post Radiation
Dropout Voltage
MSK 5940K/H RH
Group A
Subgroup
Units
1
-
0.1
1.0
-
0.1
2.0
%
2, 3
-
0.1
2.5
-
-
-
%
1
-
1.0
2.0
-
1.0
2.0
%
1
-
0.7
1.1
-
0.8
1.2
V
1
-
0.7
1.2
-
0.8
1.2
V
1
-
0.2
0.5
-
0.2
0.6
%
2, 3
-
0.3
2.0
-
-
-
%
1
-
0.3
1.5
-
0.3
1.5
%
1
-
0.1
0.2
-
0.1
0.6
%
2, 3
-
0.2
0.75
-
-
-
%
1
-
0.2
1.0
-
0.2
1.0
%
1
-
4.5
10
-
4.5
12
mA
mA
2, 3
-
4.5
10
-
-
-
Vin = Vout + 5V
-
3.0
3.5
-
3.0
3.5
-
A
Iout = 3A; Cout = 25µF; F = 120Hz
-
-
75
-
-
75
-
dB
Junction to Case at 125°C
-
-
4.2
4.6
-
4.2
4.6
°C/W
PART NUMBER
OUTPUT VOLTAGE
7
MSK5940-5.0RH
-5.0V
MSK5940-5.2RH
-5.2V
MSK5940-10RH
-10.0V
MSK5940-12RH
-12.0V
MSK5940-15RH
-15.0V
NOTES:
1
Output is decoupled to ground using 33µF minimum, low ESR capacitors unless otherwise specified.
2
Guaranteed by design but not tested. Typical parameters are representative of actual device performance but are for reference only. Not applicable to post
irradiation performance.
3
All output parameters are tested using a low duty cycle pulse to maintain TJ = TC.
4
Industrial grade devices shall be tested to subgroup 1 unless otherwise specified.
5
Military grade devices ("H" and "K" suffix) shall be 100% tested to subgroups 1,2 and 3.
6
Subgroup 1
2
3
TA = +25°C
TA = +125°C
TA = -55°C
7
Please consult the factory if alternate output voltages are required.
8
Input voltage (VIN= VOUT + a specified voltage) is implied to be more negative than VOUT.
9
Continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle.
10
Pre and Post irradiation limits, at 25°C, up to 100Krad TID, are identical unless otherwise specified. Post irradiation performance is guaranteed by design with a 2X
radiation design margin.
2
8548-56 Rev. K 2/18
APPLICATION NOTES
BYPASS CAPACITORS
OVERLOAD SHUTDOWN
For most applications a 33uF minimum, low ESR (0.5-2 ohm)
tantalum capacitor should be attached as close to the regulator's
output as possible. This will effectively lower the regulator's
output impedance, increase transient response and eliminate any
oscillations that are normally associated with low dropout regulators.
Additional bypass capacitors can be used at the remote load
locations to further improve regulation. These can be either of the
tantalum or the electrolytic variety. Unless the regulator is located
very close to the power supply filter capacitor(s), a 4.7uF minimum
low ESR (0.5-2 ohm) tantalum capacitor should also be added to the
regulator's input. An electrolytic may also be substituted if desired.
When substituting electrolytic in place of tantalum capacitors, a good
rule of thumb to follow is to increase the size of the electrolytic by
a factor of 10 over the tantalum value.
The MSK 5940RH features both power and thermal overload
protection. When the maximum power dissipation is not exceeded,
the regulator will current limit slightly above its 3 amp rating. As the
Vin-Vout voltage increases, however, shutdown occurs in relation to
the maximum power dissipation curve. If the device heats enough to
exceed its rated die junction temperature due to excessive ambient
temperature, improper heat sinking etc., the regulator will shutdown
until an appropriate junction temperature is maintained. It should
also be noted that in the case of an extreme overload, such as a
sustained direct short, the device may not be able to recover. In
these instances, the device must be shut off and power reapplied
to eliminate the shutdown condition.
HEAT SINKING
LOAD REGULATION
To determine if a heat sink is required for your application and if so,
what type, refer to the thermal model and governing equation below.
For best results the ground pin should be connected directly to
the load as shown below, this effectively reduces the ground loop
effect and eliminates excessive voltage drop in the sense leg. It is
also important to keep the output connection between the regulator
and the load as short as possible since this directly affects the load
regulation. For example, if 20 gauge wire were used which has a
resistance of about .008 ohms per foot, this would result in a drop
of 8mV/ft at 1Amp of load current. It is also important to follow the
capacitor selection guidelines to achieve best performance. Refer
to Figure 1 for connection diagram.
Governing Equation: Tj = Pd x (Rθjc + Rθcs + Rθsa) + 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 = Heat Sink Temperature
MSK 5940RH TYPICAL APPLICATION:
Low Dropout Negative Power Supply
EXAMPLE:
This example demonstrates an analysis where the regulator is at
one-half of its maximum rated power dissipation, which occurs when
the output current is at 1.5 amps.
Conditions for MSK 5940-5RH:
Vin = -7.0V; Iout = -1.5A
1.) Assume 45° heat spreading model.
2.) Find regulator power dissipation:
Pd = (Vin - Vout)(Iout)
Pd = (-7-(-5))(-1.5)
= 3.0W
FIGURE 1
TOTAL DOSE RADIATION TEST
PERFORMANCE
3.) For conservative design, set Tj = +125°C Max.
4.) For this example, worst case Ta = +90°C.
5.) Rθjc = 4.6°C/W from the Electrical Specification Table.
6.) Rθcs= 0.15°C/W for most thermal greases.
7.) Rearrange governing equation to solve for Rθsa:
Rθsa = ((Tj - Ta)/Pd) - (Rθjc) - (Rθcs)
= ((125°C - 90°C)/3.0W) - 4.6°C/W - 0.15°C/W
= 6.9°C/W
Radiation performance curves for TID testing have been
generated for all radiation testing performed by MS Kennedy.
These curves show performance trends throughout the TID test
process and are located in the MSK 5940RH radiation test report.
The complete radiation test report is available in the RAD HARD
PRODUCTS section on the MSK website.
http://www.mskennedy.com/store.sp?pid=9951&catid=19680
In this case the result is 6.9°C/W. Therefore, a heat sink with a
thermal resistance of no more than 6.9°C/W must be used in this
application to maintain the regulator junction temperature under
125°C.
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8548-56 Rev. K 2/18
TYPICAL PERFORMANCE CURVES
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8548-56 Rev. K 2/18
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=3.2 GRAMS TYPICAL
ORDERING INFORMATION
MSK5940-5.0 H RH D
LEAD CONFIGURATIONS
S= STRAIGHT; U= BENT UP; D= BENT DOWN
RAD HARD
SCREENING
BLANK= INDUSTRIAL; H= MIL-PRF-38534 CLASS H;
K=MIL- PRF-38534 CLASS K
OUTPUT VOLTAGE
5.0=-5.0V; 5.2=-5.2V; 10=-10.0V; 12=-12.0V; 15=-15.0V
GENERAL PART NUMBER
The above example is a -5.0V, Class H Military regulator with bent down leads.
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8548-56 Rev. K 2/18
REVISION HISTORY
REV
H
J
K
STATUS
Released
Released
Released
DATE
09/17
10/17
02/18
DESCRIPTION
Update parameters to better correlate to manufacturer's pre and post RAD specs.
Add -15V back to table on page 2
GBD Dropout Voltage
ANAREN, MSK Products
www.anaren.com/msk
The information contained herein is believed to be accurate at the time of printing. Anaren, MSK products 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.
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8548-56 Rev. K 2/18