MIL-PRF-38534 AND 38535 CERTIFIED FACILITY
RAD HARD 3.5A
SWITCHING REGULATOR
5048RH
FEATURES:
Manufactured using
Rad Hard RH1959MILDICE
Radiation Hardened to 100 Krad(Si) (Method 1019.8 Condition A)
Improved Replacement for Satcon SAT8565P
Adjustable Output Voltage Down to 1.21V
Input Voltage Range from 4.3V to 16V
500KHz or Externally Synchronizable Switching Frequency
Short Circuit and Thermal Limit Protection
Available in 3 Lead Form Options: Straight, Down and Gull Wing
Available to DLA SMD 5962R11232
Single Event Effect Tested
DESCRIPTION:
The MSK5048RH 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 or synchronizable switching frequency. The switching
frequency can be controlled by an external signal through the SYNC pin or be set to a constant 500KHz. Short circuit current
limit and thermal shutdown features provide fault protection. The MSK5048RH 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
POL Applications
Satellite System Power Supply
Microprocessor, FPGA Power Source
High Efficiency Low Voltage Subsystem
Power Supply
1
2
3
4
5
CASE
1
VIN
FB
VOUT
SYNC
COMP
GND
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ABSOLUTE MAXIMUM RATINGS
VIN
IOUT
Input Voltage
Output Current 9
SYNC Pin Voltage
10
TST Storage Temperature Range 11
-65°C to +150°C
TLD Lead Temperature Range 11
(10 Seconds)
300°C
TJ Junction Temperature
150°C
TC Case Operating Temperature Range
MSK5048K/HRH
-55°C to +125°C
MSK5048RH
-40°C to +85°C
ESD Rating
3A
16V
4A
7.0 V
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 2 for typical application circuit.
Guaranteed by design but not tested. Typical parameters are representative of actual device performance but are for reference only.
Reference SYNC pin function in the Application Notes section herein.
Verified during line regulation test.
Industrial grade and 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 1,4,7 TA= TC =+25°C
2,5,8A TA= TC =+125°C
3,6,8B 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.
Internal solder reflow temperature is 180°C, do not exceed.
Pre and Post irradiation limits at 25°C, up to 100 Krad(Si) TID, are identical unless otherwise specified.
Reference DSCC SMD 5962R11232 for electrical specification for devices purchased as such.
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APPLICATION NOTES
PIN FUNCTIONS
SETTING THE OUTPUT VOLTAGE
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 input pin and case ground (see
Figure 1) are recommended to minimize voltage spikes. VIN should be connected to a low impedence source for best operation.
The output voltage of the MSK5048RH is set with a simple resistor
divider network: see Figure 2 (Typical Application Circuit). Select
the resistor values to divide the desired output down to equal VFB
(1.21V nominal) at the FB pin. Use a 2.5K or lower value resistor for
R2 to keep output error due to FB pin bias current less than 0.1%.
VOUT=VFB*(1+R1/R2)
FB - The FB (feedback) pin's primary function is to set the output voltage. Use
a resistive divider from VOUT to GND to set the voltage at the feedback pin
to 1.21V when the output voltage is at the desired level. 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.
R1=R2*((VOUT/VFB)-1)
Given VFB=1.21V Nominal
TOTAL DOSE RADIATION AND SEE TEST
PERFORMANCE
CASE - The CASE GND 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 MSK5048RH to a minimum.
Use heavy copper traces or a ground plane to minimize voltage drops and
regulation error use the case ground connection to decouple the input as
close to the VIN pin as possible (see Figure 1).
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 MSK5048RH 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
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.
COMP - The COMP pin is the output of the error amplifier and the input of the
peak current comparator. This pin is typically used for frequency compensation
but can also be used as a current clamp or as an override to the internal error
amplifier control. The pin voltage is typically around 1V at light load and 2V at
heavy load. Driving the pin low will shut down the regulator. Driving it high will
increase the output current. The current into the COMP pin must be limited
to 4mA when driving it high.
SYNC - The SYNC pin is used to synchronize the oscillator to an external
clock. It is logic compatible and can be driven to any frequency between the
free run frequency (500KHz nominal) and 1MHz. At frequencies greater than
700KHz the risk of sub harmonic oscillation increases for applications with
duty cycles greater than 50%. This is the result of the magnitude of the slope
compensation ramp generated by the control IC being limited at higher frequencies. The duty cycle of the input signal must be between 10% and 90%
to ensure proper synchronization. Tie the SYNC pin to GND if it is not used.
FIGURE 2
SELECTING THE OUTPUT CAPACITOR
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:
VP-P=IP-P*ESR
Where IP-P=VOUT*(VIN-VOUT)/(1.65*VIN)
The typical ESR range for an MSK5048RH 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(CAP)=IP-P/(8*F*C)
Where:
C=output capacitance in Farads
F=Switching Frequency in Hertz
Select a capacitor or combination of capacitors that can tolerate the worstcase 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.
FIGURE 1
3
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TYPICAL PERFORMANCE CURVES
4
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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.
225
80
180
80
180
60
135
60
135
40
90
40
90
20
45
20
45
0
0
0
0
GAIN (dB)
PHASE (deg)
100
-20
-45
-40
-90
-40
-135
-60
-180
-80
-225
-100
-80
-100
1000
10000
100000
1000000
-90
VIN = 5.0V
VOUT = 2.5V
IOUT = 1.0A
COMPENSATION = 1500pF
-135
-180
-225
1000
FREQUENCY (Hz)
10000
100000
1000000
FREQUENCY (Hz)
GAIN AND PHASE vs. FREQUENCY
100
225
80
180
60
135
40
90
20
45
0
0
-45
-20
-40
-60
-80
-90
VIN = 5.0V
VOUT = 3.3V
IOUT = 1.0A
COMPENSATION = 1500pF
-135
-180
-225
-100
1000
PHASE (deg)
-60
VIN = 5.0V
VOUT = 1.5V
IOUT = 1.0A
COMPENSATION = 1500pF
-45
-20
PHASE (deg)
GAIN AND PHASE vs. FREQUENCY
225
GAIN (dB)
GAIN (dB)
GAIN AND PHASE vs. FREQUENCY
100
10000
100000
1000000
FREQUENCY (Hz)
5
8548-26 Rev. L 2/15
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=7.7 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5048 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 DLA SMD 5962R11232 for DLA part number options.
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8548-26 Rev. L 2/15
MECHANICAL SPECIFICATIONS
ESD TRIANGLE INDICATES PIN 1
WEIGHT=7.87 GRAMS TYPICAL
ALL DIMENSIONS ARE SPECIFIED IN INCHES
ORDERING INFORMATION
MSK5048 K RH U
LEAD CONFIGURATIONS
S= STRAIGHT; U= BENT DOWN; 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 DLA SMD 5962R11232 for DLA part number options.
7
8548-26 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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