MIL-PRF-38534 AND 38535 CERTIFIED FACILITY
RAD HARD 3.5A
SWITCHING REGULATOR
5044RH
FEATURES:
Manufactured using
Rad Hard RH1959MILDICE
Radiation Hardened to 100 Krad(Si) (Method 1019.8 Condition A)
Improved Replacement for Satcon SAT8565A
Adjustable Output Voltage Down to 1.21V
Input Voltage Range from 4.3V to 16V
Constant 500KHz Switching Frequency
Shutdown Pin
Short Circuit and Thermal Limit Protection
Available in 4 Lead Form Options: Straight, Up, Down and Gull Wing
Available to DSCC SMD 5962R11231
Single Event Effect Tested
DESCRIPTION:
The MSK5044RH is a radiation hardened adjustable output voltage switching regulator. A wide input and output voltage
range with 3.5A output current capability make these regulators suitable for many applications. Excellent efficiency and a
reduced output capacitance requirement are the results of a constant 500KHz switching frequency. The regulator output can
be turned on and off remotely with low current logic levels via the shutdown pin for meeting power sequencing requirements.
Short circuit current limit and thermal shutdown features provide fault protection. The MSK5044RH is hermetically sealed in
a space saving 5 pin power package and specifically designed for space/satellite applications.
EQUIVALENT SCHEMATIC
PIN-OUT INFORMATION
TYPICAL APPLICATIONS
1 VIN
2 GND
3 VOUT
4 SHDN
5 FB
CASE=ISOLATED
POL Applications
Satellite System Power Supply
Microprocessor, FPGA Power Source
High Efficiency Low Voltage Subsystem
Power Supply
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8548-30 Rev. L 2/15
ABSOLUTE MAXIMUM RATINGS
VIN
IOUT
Input Voltage
Output Current 8
SHDN Pin Voltage
9
TST Storage Temperature Range 12
TLD Lead Temperature Range 10
(10 Seconds)
TJ Junction Temperature
TC Case Operating Temperature Range
MSK5044K/H RH
MSK5044RH
ESD Rating
16V
4A
7.0 V
-65°C to +150°C
300°C
150°C
-55°C to +125°C
-40°C to +85°C
3A
ELECTRICAL SPECIFICATIONS
NOTES:
1
2
3
4
5
6
7
8
9
10
11
12
13
Unless otherwise specified VIN=5.0V, VOUT=2.5V and IOUT=1.0A. See Figure 1 for typical application circuit.
Guaranteed by design but not tested. Typical parameters are representative of actual device performance but are for reference only.
Verified during line regulation test.
Industrial grade devices shall be tested to subgroup 1 and 4 unless otherwise specified.
Military grade devices ("H" Suffix) shall be 100% tested to subgroups 1,2,3 and 4.
Subgroup 5 & 6 testing available on request.
Subgroup 1,4 TA = TC =+25°C
2,5 TA = TC =+125°C
3,6 TA = TC =-55°C
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. The absolute maximum current of 4.0A applies at duty cycles of 0.75 and lower.
De-rate linearly from 4.0A at D=0.75 to 3.0A at D=1.0.
Continuous operation at or above absolute maximum ratings may adversely effect the device performance and/or life cycle.
The internal case temperature must not exceed 175°C under any conditions.
Pre and Post irradiation limits at 25°C, up to 100 Krad(Si) TID, are identical unless otherwise specified.
Internal solder reflow temperature is 180°C, do not exceed.
Reference DSCC SMD 5962R11231 for electrical specification for devices purchased as such.
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8548-30 Rev. L 2/15
APPLICATION NOTES
PIN FUNCTIONS
SELECTING THE OUTPUT CAPACITOR
VIN - VIN connects to the collector of the internal power switch and
provides power to the internal control circuitry and internal regulator.
Very high di/dt is seen at VIN during switch on and off transitions.
High frequency decoupling capacitors mounted in close proximity
to the VIN and ground pins are recommended to minimize voltage
spikes. VIN should be connected to a low impedence source for
best operation.
The output capacitor filters the ripple current from the internal
inductor to an acceptable ripple voltage seen by the load. The primary factor in determining voltage ripple is the ESR of the output
capacitor. The voltage ripple can be approximated as follows:
FB - The FB (feedback) pin's primary function is to set the output
voltage to the desired level. Use a single resistor between VOUT
and FB to form a feedback divider network with the internal 2.49K
resistor. Select the external resistor value to set the voltage at the
FB pin to 1.21V when the output is at the desired level, see "Setting
The Output Voltage."The FB pin provides two additional functions.
If the voltage at the FB pin drops below 0.8V the switch current limit
is reduced. When the voltage at the FB pin drops below 0.7V the
switching frequency is reduced. The switching frequency reduces
to approximately 100KHz at VFB<=0.4V.
The typical ESR range for an MSK5044RH application is between
0.05 and 0.20 ohm. Capacitors within these ESR ranges typically
have enough capacitance value to make the capacitive term of
the ripple equation insignificant. The capacitive term of the output
voltage ripple lags the ESR term by 90° and can be calculated as
follows:
VP-P=IP-P*ESR
Where IP-P=VOUT*(VIN-VOUT)/(1.65*VIN)
VP-P(CAP)=IP-P/(8*F*C)
Where:
C=output capacitance in Farads
F=Switching Frequency in Hertz
GND - The GND pin provides a return path for all internal control
current and acts as a reference to the error amplifier. It is important
that it is at the same voltage potential as the load return to ensure
proper regulation. Keep current on the ground between the load
and the MSK5044RH to a minimum and use heavy copper traces
to minimize voltage drops and regulation error.
Select a capacitor or combination of capacitors that can tolerate the
worst-case ripple current with sufficient de-rating. When using multiple capacitors in parallel to achieve ESR and/or total capacitance,
sharing of ripple current between capacitors will be approximately
equal if all of the capacitors are the same type and preferably from
the same lot. Low ESR tantalum capacitors are recommended over
aluminum electrolytic. The zero created by the ESR of the capacitor
is necessary for loop stabilty. A small amount of ceramic capacitance
close to the load to decouple high frequency is acceptable but it
should not cancel the ESR zero.
SHDN - The SHDN (shutdown) pin has two shutdown functions. The
first function disables switching when the voltage on the pin drops
below 2.38V (nominal). The second forces a complete shutdown
minimizing power consumption when the voltage drops below 0.4V
(nominal). Pull this pin high or leave open for normal operation. The
2.38V threshold can be used for UVLO functions by configuring a
resistive divider to VIN and GND that holds the pin voltage below
2.38V until VIN rises to the minimum desired voltage.
CURRENT LIMIT
The MSK5044RH typically current limits at 3.75A. The output voltage
will begin to drop when the current limit is reached. If the output
voltage drops below 66% of the programmed level the output current
limit level will be reduced to protect a shorted or latched up load
circuit from a continuous high current condition. The current limit
reduction is controlled by the voltage at feedback pin and can be
defeated if it is undesired. A simple clamp circuit to prevent the feedback voltage from dropping below a nominal 0.8V will prevent the
fold back current condition. The foldback occurs when the feedback
voltage drops below 0.8V and the normal in regulation feedback
voltage is 1.21V. Clamping the feedback pin to a voltage between
0.9V and 1.1V prevents foldback and allows normal regulation.
Clamping the feedback pin will also defeat the frequency shift that
occurs when the feedback voltage drops below 0.7V.
VOUT - VOUT is the output of the regulator. External capacitance
between the VOUT pin and GND is required to maintain stability
and minimize output ripple voltage, see "Selecting The Output
Capacitor." Provide a low impedance path between VOUT and
the load to minimize voltage drops.
SETTING THE OUTPUT VOLTAGE
The output voltage of the MSK5044RH is set with a single resistor,
see Figure 1 (Typical Application Circuit). Select the value of RFB
using the formulas below.
VOUT=VFB*(1+RFB/2490)
RFB=2490*((VOUT/VFB)-1)
TOTAL DOSE RADIATION AND SEE TEST
PERFORMANCE
Given VFB=1.21V Nominal Radiation performance curves for TID testing are generated for all
radiation testing performed by MSK. These curves show performance trends throughout the TID test process and are located in
the MSK5044RH radiation test report. The complete radiation test
report is available in the RAD HARD PRODUCTS section on the
MSK website. Contact MSK for SEE test results.
TYPICAL APPLICATION CIRCUIT
FIGURE 1
3
8548-30 Rev. L 2/15
TYPICAL PERFORMANCE CURVES
4
8548-30 Rev. L 2/15
TYPICAL PERFORMANCE CURVES CONT'D
CURRENT LIMT
vs INPUT VOLTAGE
7
CURRENT LIMIT (A)
6
5
4
3
2
VOUT = 1.8V
1
4A MAX. CONTINUOUS
0
3
5
7
9
11
13
15
11
13
15
INPUT VOLTAGE (V)
CURRENT LIMIT
vs INPUT VOLTAGE
6
CURRENT LIMIT (A)
5
4
3
2
VOUT = 3.3V
1
4A MAX. CONTINUOUS
0
3
5
7
9
INPUT VOLTAGE (V)
5
8548-30 Rev. L 2/15
TYPICAL PERFORMANCE CURVES CONT'D
GAIN AND PHASE RESPONSE
The gain and phase response curves are for the MSK typical application circuit and are representative of typical device performance, but are for reference only. The performance should be analyzed for each application to insure individual program
requirements are met. External factors such as temperature, input and output voltages, capacitors, etc. all can be major
contributors. Please consult factory for additional details.
80
200
60
150
60
150
40
100
40
100
20
50
20
50
0
0
0
0
-50
VIN = 5.0V
VOUT = 1.5V
IOUT = 1.0A
COUT = 2X 220µF
(TAZH227K010L)
-60
-80
0.1
1
10
100
-20
-100
-40
-150
-60
-200
-80
1
-150
10
100
1000
FREQUENCY (kHz)
FREQUENCY (kHz)
MSK5044RH GAIN AND PHASE vs. FREQUENCY
MSK5044RH GAIN AND PHASE vs. FREQUENCY
80
200
80
200
60
150
60
150
40
100
40
100
20
50
20
50
0
0
0
0
-50
VIN = 5.0V
VOUT = 1.5V
IOUT = 2.0A
COUT = 2X 220µF
(TAZH227K010L)
-40
-60
-80
0.1
1
10
100
GAIN (dB)
-20
PHASE (deg)
GAIN (dB)
-100
-200
0.1
1000
-50
VIN = 5.0V
VOUT = 1.5V
IOUT = 2.0A
COUT = 2X 220µF
(TAZH227K010L)
-20
-100
-40
-150
-60
-200
-80
1000
-100
-150
-200
0.1
FREQUENCY (kHz)
-50
VIN = 5.0V
VOUT = 2.5V
IOUT = 2.0A
COUT = 2X 220µF
(TAZH227K010L)
PHASE (deg)
-40
GAIN (dB)
-20
PHASE (deg)
GAIN (dB)
200
PHASE (deg)
MSK5044RH GAIN AND PHASE vs. FREQUENCY
MSK5044RH GAIN AND PHASE vs. FREQUENCY
80
1
10
100
1000
FREQUENCY (kHz)
6
8548-30 Rev. L 2/15
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=7.7 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5044 K RH GW
LEAD CONFIGURATIONS
GW= GULL WING
RADIATION HARDENED
SCREENING
BLANK= INDUSTRIAL; H=MIL-PRF-38534 CLASS H;
K=MIL-PRF-38534 CLASS K
GENERAL PART NUMBER
The above example is a Class K switching regulator with gull wing leads.
NOTE: See DSCC SMD 5962R11231 for DSCC part number options.
7
8548-30 Rev. L 2/15
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=7.6 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5044 K 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 a Class K switching regulator with leads bent up.
NOTE: See DSCC SMD 5962R11231 for DSCC part number options.
8
8548-30 Rev. L 2/15
REVISION HISTORY
MSK
www.anaren.com/msk
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.
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8548-30 Rev. L 2/15