MIL-PRF-38534 CERTIFIED
M.S.KENNEDY CORP.
RAD HARD
NEGATIVE, 3 AMP,
LOW DROPOUT
VOLTAGE REGULATOR
5940RH
SERIES
(315) 701-6751
4707 Dey Road Liverpool, N.Y. 13088
FEATURES:
Manufactured using
Space Qualified RH1185 Die
-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, Down and Gull Wing
Alternate Output Voltages Available
Available with Top Tab or Tabless Package
Total Dose Tested to TBDK RAD (Method 1019.7 Condition A)
Contact MSK for MIL-PRF-38534 Qualification and Appendix G (Radiation Status)
TOP TAB
DESCRIPTION:
NO TAB
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
TYPICAL APPLICATIONS
High Efficiency Linear Regulators
Constant Voltage/Current Regulators
System Power Supplies
Switching Power Supply Post Regulators
PIN-OUT INFORMATION
1 GND
2 VIN
3 VOUT
1
PRELIMINARY
Rev. C 6/08
ABSOLUTE MAXIMUM RATINGS
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
9
T
C
-55°C to +125°C
-40°C to +85°C
○
ELECTRICAL SPECIFICATIONS
Parameter
Test Conditions
3 10
Group A
MSK 5940K/H/E RH
Typ.
0.1
0.1
0.7
0.2
0.3
0.1
0.2
4.5
4.5
3.5
75
7.0
Max.
1.0
2.0
1.0
1.0
2.0
0.5
0.75
10
10
-
-
7.2
MSK 5940RH
Min.
-
-
-
-
-
-
-
-
-
3.0
60
-
Typ.
0.1
-
0.8
0.2
-
0.1
-
4.5
-
3.5
75
7.0
Max.
2.0
-
1.2
2.0
-
0.6
-
12
-
-
-
7.5
Subgroup Min.
1
2,3
1
1
2,3
1
2,3
1
2,3
-
-
-
-
-
-
-
-
-
-
-
-
3.0
60
-
Output Voltage Tolerance
Dropout Voltage
2
Load Regulation
I
OUT
=10mA; V
IN
=V
OUT
+3V
0A≤I
OUT
≤3A; ∆V
OUT
=1%
10mA≤I
OUT
≤3A
V
IN
=V
OUT
+3V
I
OUT
=10mA
(V
OUT
+3V)≤V
IN
≤(V
OUT
+15V)
V
IN
=V
OUT
+3V; I
OUT
=10mA
V
IN
=V
OUT
+5V
I
OUT
=3A; C
OUT
=25µF; f=120Hz
JUNCTION TO CASE @ 125°C
Line Regulation
Quiescent Current
Short Circuit Current
2
Ripple Rejection
2
Thermal Resistance
2
PART
NUMBER
MSK5940-5.0RH
MSK5940-5.2RH
MSK5940-10RH
MSK5940-12RH
MSK5940-15RH
OUTPUT VOLTAGE
7
-5.0V
-5.2V
-10.0V
-12.0V
-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.
3 All output parameters are tested using a low duty cycle pulse to maintain T
J
= T
C
.
4 Industrial grade and "E" suffix 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 T
A
=T
C
=+25°C
2 T
A
=T
C
=+125°C
3 T
A
=T
C
=-55°C
7 Please consult the factory if alternate output voltages are required.
8 Input voltage (V
IN
= V
OUT
+ a specified voltage) is implied to be more negative than V
OUT
.
9 Continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle.
10 All parameter limits are pre-irradiation. Radiation performace is not yet characterized.
2
PRELIMINARY
Rev. C 6/08
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
○
-V
IN
-V
IN
P
D
I
OUT
T
J
I
OUT
Input Voltage
Input Voltage (WRT V
OUT
)
Power Dissipation
Output Current
Junction Temperature
Output Reverse Voltage
-35V
-30V
Internally Limited
-3A
+150°C
-2V
T
ST
T
LD
Storage Temperature Range
Lead Temperature Range
(10 Seconds)
Case Operating Temperature
MSK 5940K/H/E RH
MSK 5940RH
-65°C to +150°C
300°C
Units
%
%
V
%
%
%
%
mA
mA
A
dB
°C/W
APPLICATION NOTES
BYPASS CAPACITORS
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 regu-
lators. 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.
OVERLOAD SHUTDOWN
The MSK 5940RH features both power and thermal overload
protection. When the maximum power dissipation is not ex-
ceeded, 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 tem-
perature 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
To determine if a heat sink is required for your application and
if so, what type, refer to the thermal model and governing equa-
tion below.
Governing Equation: Tj = Pd x (R
θ
jc + R
θ
cs + R
θ
sa) + Ta
WHERE
Tj = Junction Temperature
Pd = Total Power Dissipation
R
θ
jc = Junction to Case Thermal Resistance
R
θ
cs = Case to Heat Sink Thermal Resistance
R
θ
sa = Heat Sink to Ambient Thermal Resistance
Tc = Case Temperature
Ta = Ambient Temperature
Ts = Heat Sink Temperature
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
3.) For conservative design, set Tj = +125°C Max.
4.) For this example, worst case Ta = +90°C.
5.) R
θ
jc = 7.2°C/W from the Electrical Specification Table.
6.) R
θ
cs = 0.15°C/W for most thermal greases.
7.) Rearrange governing equation to solve for R
θ
sa:
R
θ
sa = ((Tj - Ta)/Pd) - (R
θ
jc) - (R
θ
cs)
= ((125°C - 90°C)/3.0W) - 7.2°C/W - 0.15°C/W
= 4.3°C/W
In this case the result is 4.3°C/W. Therefore, a heat sink with a
thermal resistance of no more than 4.3°C/W must be used in this
application to maintain the regulator junction temperature under
125°C.
3
PRELIMINARY
Rev. C 6/08
LOAD REGULATION
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 dia-
gram.
MSK 5940RH TYPICAL APPLICATION:
Low Dropout Negative Power Supply
FIGURE 1
TOTAL DOSE RADIATION TEST
PERFORMANCE
Radiation performance curves for TID testing will be gen-
erated for all radiation testing performed by MS Kennedy.
These curves will show performance trends throughout the
TID test process and will be located in the MSK 5940RH
radiation test report. The complete radiation test report will
be available in the RAD HARD PRODUCTS section on the
MSK website.
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
