MIL-PRF-38534 AND 38535 CERTIFIED FACILITY
RAD HARD POSITIVE,
3 AMP, LOW DROPOUT
ADJ VOLTAGE REGULATOR
5971RH
FEATURES:
•
•
•
•
•
•
•
•
•
SMD-1
3 PAD
CERAMIC
Manufactured using
Space Qualified RH1085 Die
Total Dose Hardened to 100 Krad(Si) (Method 1019.7 Condition A)
Low Dropout Voltage
Internal Short Circuit Current Limit
Output Voltage is Adjustable with 2 External Resistors
Output Current Capability to 3 Amps
Internal Thermal Overload Protection
Available in 3 Lead Form Options: Straight, Up and Down (TO257)
Available to DSCC SMD 5962R09212
TO-257
DESCRIPTION:
The MSK 5971RH offers low dropout voltage while offering radiation tolerance for space applications. This, combined
with the low JC, allows increased output current while providing exceptional device efficiency. Because of the increased
efficiency, a small hermetic 3 pin package either SMD-1 or TO-257, can be used providing maximum performance while
occupying minimal board space. Output voltage is selected by the user through the use of 2 external resistors. Additionally,
the regulator offers internal short circuit current and thermal limiting, which allows circuit protection and eliminates the need
for external components and excessive derating. The MSK 5971RH is available in two space saving package options; the
3 pin power surface mount SMD-1 and the TO-257 package with 3 lead form options: straight, up and down.
EQUIVALENT SCHEMATIC
PIN-OUT INFORMATION
TYPICAL APPLICATIONS
•
•
•
•
High Efficiency Linear Regulators
Constant Voltage/Current Regulators
System Power Supplies
Switching Power Supply Post Regulators
1
TO-257
SMD-1
1
2
3
1
2
3
ADJ
VOUT
VIN
ADJ
VIN
VOUT
8548-130 Rev. K 11/17
ABSOLUTE MAXIMUM RATINGS
8
±VIN
Input Voltage (WRT VOUT)........................................ 30V
11
T ST Storage Temperature Range....................-65°C
to +150°C
PD
TLD Lead Temperature Range
IOUT
Power Dissipation.................................. Internally Limited
7
Output Current..............................................................
3A
TJ
Junction Temperature........................................... +150°C
TC
(10 Seconds)............................................................300°C
Case Operating Temperature
MSK5971RH............................................. -40°C to +85°C
MSK5971K/HRH..................................... -55°C to +125°C
ELECTRICAL SPECIFICATIONS
Parameter
Test Conditions
1
3
MSK5971RH
Group A MSK5971K/H RH
Subgroup Min. Typ. Max. Min. Typ. Max.
1.238 1.250 1.262 1.225 1.250 1.270
1
9
IOUT = 10mA VIN = VOUT+3V
Reference Voltage
2,3
Post Radiation
10mA IOUT 3A VOUT = 1%
Dropout Voltage
Line Regulation
Ripple Rejection
-
-
V
1
1.205
1.24
1.262 1.205 1.224 1.270
V
1
-
1.3
1.65
-
1.3
1.65
V
IOUT=10mA
1
-0.5
0.1
0.5
-
0.1
0.6
%
2,3
-0.75
0.2
0.75
-
-
-
%
VIN = VOUT +3V
1
-1.0
0.2
1.0
-
0.2
2.0
%
10mA IOUT 3A
2,3
-2.0
0.3
2.0
-
-
-
%
VIN = VOUT +5
1
3.0
4.2
-
3.0
4.2
-
A
7
2
-
V
(VOUT+3V) VIN (VOUT +15V)
Load Regulation
Short Circuit Current
1.225 1.250 1.270
Units
1
3.0
4.1
-
3.0
4.1
-
A
IOUT = 3A; COUT = 25µF; f = 120Hz
Post Radiation
-
-
75
-
-
75
-
dB
Thermal Resistance
2
Junction to Case @ 125°C TO-257 Package
-
-
3.0
3.5
-
3.0
3.5
°C/W
Thermal Resistance
2
Junction to Case @ 125°C SMD-1 Package
-
-
2.0
2.5
-
2.0
2.5
°C/W
NOTES:
1
Output is decoupled to ground using 10µF low ESR tantalum capacitor 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 and 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
Subgroup 2
Subgroup 3
7
The output current limit function provides protection from transient overloads but it may exceed the maximum continuous rating. Continuous
operation in current limit may damage the device. For compliance with MIL-STD 833 revision C current density specifica tions, the MSK 5971RH
is derated to 2 amps.
8
Continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle.
9
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.
TA = TC = +25°C
TA = TC = +125°C
TA = TC = -55°C
10
Reference DSCC SMD 5962R09212 for electrical specification for devices purchased as such.
11
Internal solder reflow temperature is 180°C, do not exceed.
2
8548-130 Rev. K 11/17
APPLICATION NOTES
BYPASS CAPACITORS
LOAD REGULATION
Minimum requirement for output capacitance is 10µF, low
ESR tantalum. A 22µF low ESR (0.5-2 ohm) tantalum capacitor
attached close to the regulator's output will ensure stability in
most applications. 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
With a three-terminal device, it is not possible to provide true
remote load sensing. The resistance of the connection to the load
will limit the load regulation of the device. The best load regulation
will be achieved when the top of the divider is connected to the
pin as close to the case of the MSK 5971RH as possible and the
bottom of the divider as close to the load as possible. This will
effectively reduce the effect of the parasitic line resistance on the
load regulation of the device.
Refer to Figure 2 for proper connections.
FIGURE 2
OUTPUT VOLTAGE
RIPPLE REJECTION
The MSK 5971RH develops a 1.250 Volt reference between
the output pin and the adjust pin. A resistor, R1, is placed between
the output and adjust pins, causing current to flow through R1 and
down through R2, setting the output voltage. R1 may be chosen
to sink the minimum required load current of 10mA. Refer to Figure
1 for connections and Vout calculation.
The typical curve for ripple rejection is shown with the adjust
pin bypassed as shown in Figure 3. For proper bypassing and ripple
rejection approaching the values of the curve, the impedance of
the adjust pin capacitor at the ripple frequency should be less than
the value of R1. The value of the adjust pin capacitor is a function
of the input ripple frequency. For instance, if R1=100, at 120Hz
the adjust pin capacitor should be 25µF. At 10KHz only 0.22uF is
required.
FIGURE 1
FIGURE 3
3
8548-130 Rev. K 11/17
APPLICATION NOTES CONT'D
OVERLOAD SHUTDOWN
HEAT SINKING
The regulator features both power and thermal overload
protection. When the maximum power dissipation is not exceeded,
the regulator will current limit slightly above it's 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 also shuts
down 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.
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.
Governing Equation: Tj = Pd x (Rjc + Rqcs + Rsa) + Ta
WHERE
Tj = Junction Temperature
Pd = Total Power Dissipation
Rjc = Junction to Case Thermal Resistance
Rcs = Case to Heat Sink Thermal Resistance
Rsa = Heat Sink to Ambient Thermal Resistance
Tc = Case Temperature
Ta = Ambient Temperature
Ts = Heat Sink Temperature
EXAMPLE:
TOTAL DOSE RADIATION TEST
PERFORMANCE
This example demonstrates an analysis of the TO-257 package
with the regulator operating at one-half of its maximum rated
output current.
Radiation performance curves for TID testing will be generated
for all radiation testing performed by MS Kennedy. These curves will
show performance trends throughout the TID test process and can
be located in the MSK 5971RH radiation test report. The complete
radiation test report will be available in the RAD HARD PRODUCTS
section on the MSK website.
Conditions for MSK 5971RH:
VIN = +8.0V; Iout = +1.5A
1)
2)
Assume 45° heat spreading model.
Find positive regulator power dissipation:
Pd = (VIN - VOUT) (Iout)
Pd = (8-5)(1.5)
= 4.5W
3)
4)
5)
6)
7)
For conservative design, set Tj = +125°C Max.
For this example, worst case Ta =+90°C.
Rjc = 3.5°C/W from the Electrical Specification Table.
Rcs= 0.15°C/W for most thermal greases.
Rearrange governing equation to solve for Rsa:
Rsa = ((Tj - Ta)/Pd) - (Rjc) - (Rcs)
= (125°C - 90°C)/4.5W - 3.5°C/W - 0.15°C/W
= 4.1 °C/W
In this case the result is 4.1°C/W. Therefore, a heat sink with
a thermal resistance of no more than 4.1°C/W must be used in this
application to maintain regulator circuit junction temperature under
125°C.
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8548-130 Rev. K 11/17
TYPICAL PERFORMANCE CURVES
5
8548-130 Rev. K 11/17
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=3.2 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5971 H RH U
LEAD CONFIGURATIONS
S= STRAIGHT; U= BENT UP; D= BENT DOWN
RADIATION HARDENED
SCREENING
BLANK= INDUSTRIAL; H=MIL-PRF-38534 CLASS H;
K=MIL-PRF-38534 CLASS K
GENERAL PART NUMBER
The above example is an adjustable Class K regulator with leads bent up.
Ordering information for the 3 pad ceramic SMD-1 package is contained on the next page.
NOTE: See DSCC SMD 5962R09212 for DSCC part number options.
6
8548-130 Rev. K 11/17
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=3.2 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5971 K RH L
3 PAD CERAMIC SMD-1 PACKAGE
RADIATION HARDENED
SCREENING
BLANK= INDUSTRIAL; H=MIL-PRF-38534 CLASS H;
K=MIL-PRF-38534 CLASS K
GENERAL PART NUMBER
The above example is an adjustable Class K regulator.
NOTE: See DSCC SMD 5962R09212 for DSCC part number options.
7
8548-130 Rev. K 11/17
REVISION HISTORY
REV
H
J
K
STATUS
Released
Released
Released
DATE
07/14
09/17
11/17
DESCRIPTION
Update format, assign form number and add internal solder note.
Update parameters to better correlate to manufacturer's pre and post rad specs.
Change output curent maximum to 3A
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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8548-130 Rev. K 11/17