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> **Hybrid DC to DC Power Converter Issues Overview: Needs Vs. Supply
> Chain**

**Authors:** Philip B. Gagne - T3 Aerospace

## L. G. Zambotti - T3 Aerospace

John W. Parker - SAIC

Ken Jacobs - SAIC

## R. J. Reaney - T3 Aerospace

John E. Pandolf - NASA

James F. Bockman - NASA

**Editor:** Jeannette Plante -- Dynamic Range Corporation

#### Prepared for the NASA EEE Parts Assurance Group

May 20, 2005

**[Executive Summary]{.underline}**

Our survey of Direct Current to Direct Current (DC to DC) hybrid power
converter availability for NASA systems uncovered a staggering small
quantity that are fully qualified for space use in a relatively healthy
overall market. The lack of reuse of electrical designs further
frustrates our ability to find qualified product to satisfy all of the
Agency's converter needs. Technology advances and new discoveries about
semiconductor failure modes in the ionizing radiation environment of
space continue to impede qualification of new part numbers. Some new
technology strategies such as the move toward more modular systems is
expect to improve part reuse and reduce the need for new qualified
parts. Other technology advances such as low voltage, high speed chips
will have the opposite effect.

**[Introduction]{.underline}**

DC to DC Converters are used in civil and military aerospace equipment
to provide regulated voltage and current sources to subsystems which are
clients of the main system's power bus. In a typical satellite system,
the solar arrays are designed to provide a 28V main bus voltage. The
subsystems need that voltage converted to levels that are applicable to
their functionality: 5.0V, 3.3V and 2.5V for digital subsystems and ±12V
and ±15V for analog subsystems. Examples of typical satellite subsystem
loads are a computer, a motor, a transmitter and a laser firing control
system. Other NASA spacecraft such as the Orbiter and the Space Station,
have different bus voltages however their subsystems need the same 5.0V,
3.3V, ±12V and ±15V source voltages. Power and regulation requirements
vary widely across the various subsystem and spacecraft applications. DC
to DC converters are primary building blocks of the power system and
critical nodes throughout the avionics of a spacecraft (Figure 1.).

In all spacecraft designs, mass and volume are rationed among the
subsystems making miniaturization highly valued. This has lead to a
heightened demand for miniaturized DC to DC converters and many are
offered on the market by many vendors. Rather than building up a
converter using discrete parts on a traditional printed circuit card,
the converter, sometimes with electromagnetic interference (EMI) filter
circuits included, is built up in a relatively small metal package using
hybrid microcircuit electronic packaging technology. These are referred
to as hybrid DC to DC converters. Hybrid DC to DC converters are sold in
a variety of styles which vary foremost by input voltage, output voltage
(single, dual and triple output voltages are offered), power efficiency
and maximum output power. The styles offered continually change to keep
pace with the ever changing needs of the design community which includes
space hardware designers.

The total space market for DC to DC Converters is small in comparison to
the industrial, military and commercial markets yet the variety of
product types required is high. The result is that the vendors pick what
they consider to be broadly applicable designs defined by what are
considered in the commercial industry to be key discriminating
characteristics: power, physical size, number and types of outputs, and
efficiency. This concept that a few part types can be applied in a wide
range of designs and that selection can be based on just a few
characteristics keeps the "solution set" small and has actually led to
power system functionality problems. These problems arise from a common
misconception in the industry that a "high" power converter can be used
for all power needs from 0 to Pmax. These converters are designed with
an operational "sweet spot" based on load level and type, input
impedance and other circuit/system conditions. Use of the parts outside
of this sweet spot has been found in several cases to lead to device
instability and failure. The trend toward increased power management
directly at the consuming device rather than at the bus level may
exacerbate application problems if it does not drive the qualification
of new, special-purpose part types.

**[Space Market Analysis]{.underline}**

The size of the current space electronics market can be estimated
several ways, most common are the top down method, based upon total
planned spacecraft, and the bottom-up approach that looks at the current
sales of worldwide semiconductor electronics.

From a top down perspective the Aerospace Industries Association
projected the aerospace market for 2002 at approximately \$153 billion.
DoD accounted for \$57 billion, NASA approximately \$13 billion, \$42
billion for civilian aircraft, and upgrades and maintenance accounted
for the remaining sales. NASA's budget for aerospace in 2003 was \$13.4
billion and projected to be \$13.6 billion in 2004. Estimating the size
of the space hybrid DC to DC power converter market from this data
requires determination of two factors. First is the percentage of the
aerospace market that is related to onboard power converters and the
second the percentage of the aerospace market that is space related. The
first was estimated at 0.5% the latter at 32%. Applying the first factor
to the \$153 billion total market provides an estimate of the entire
aerospace hybrid DC to DC power converters including those for space.
The space related portion of the \$765 million market is obtained by
applying the second factor. The top-down approach estimated that portion
of the market at \$245 million.

From a bottom-up perspective the 2003 total worldwide semiconductor
market was projected at \$166 billion. These estimates are from multiple
sources. According to Semico Research Corporation the military portion
of the market is 1.1% or \$2.3 billion. NASA and civilian space is
estimated at an additional \$630 million for a total military and space
electronic market of \$2.94 billion. However, from this point the
analysis is much more difficult. The percentage of the military market
that is space related is extremely difficult to determine. Also the
numbers only reflect the cost of semiconductor electronics and not the
cost of assembly, non-semiconductor parts, testing, qualification,
configuration management, and related space programmatics. It is not
unusual for space-based assemblies costing \$100,000 to only have a
semiconductor BOM (bill of material) valued at less than \$25,000. Our
rough estimates using a bottom-up approach places the market for space
hybrid DC to DC power converters between \$250 million and \$300
million.

Therefore, based upon the two approaches we estimate the hybrid DC to DC
power converter market in the range of \$200 million to \$300 million.

**[Availability of Space Grade Product Through the Mil-Spec
System]{.underline}**

In the absence of a NASA specification and qualification system for
electronic parts, the Agency leverages heavily off of the military
specification (mil-spec) system and measures availability of products
for space systems with respect to that system. The Defense Supply Center
Columbus (DSCC) is the logistics management organization for military
specifications for electronic parts including hybrid microcircuits, of
which DC/DC converters are one type. There are thirty-nine manufacturers
listed by DSCC in their QML-38534 Hybrid Microcircuit Program Status as
of August 2004. Table 1 shows the manufacturers DSCC has certified as of
the 3^rd^ quarter of 2004 as having a production line process that meets
the requirements of MIL-PRF-38534, *Hybrid Microcircuits, General
Specification for*. This list applies for all types of hybrid
microcircuits in the mil-spec system, not just DC to DC converters.
There are six DSCC-certified lines that are active in the power/DC to DC
converter area: Aeroflex, Crane Interpoint, International Rectifier,
M.S.Kennedy, Natel Engineering and VPT/Delta.

MIL-PRF-38534E defines requirements based on two levels of intended
application: one for high reliability ground and aeronautics
applications (standard military level or Class H) and one for high
reliability space (Class K) (see paragraph 1.3
[Classification]{.underline} of the specification). DSCC has clarified
the standard military level as "designed to be used only in non-space
applications". The assumption that Class H devices can be replaced when
they fail in service is a factored into the way they are specified and
built, therefore, MIL-PRF-38534 Class K devices are considered preferred
for space use on the basis of risk of failure.

Class K devices, though preferred for space use, may not be guaranteed
for a Total Ionizing Dose (TID) radiation tolerance level above 50
kRads(Si) or any level of protection in an energetic particle (Single
Event Effect, SEE) environment. Further, though these devices have long
been tested and approved for use in space, recent discoveries have found
that these devices may not be as radiation hard as prior high dose rate
testing has indicated due to the low dose rate or ELDRS (Extremely Low
Dose Rate Sensitivity) effect. This has created a renewed concern over
the type of testing that needs to be applied to assure that the linear
devices inside of DC to DC converters are sufficiently radiation hard
whether they are of mil-spec pedigree or not.

In order to be able to sell a Class K DC to DC converter, the vendor
must first have their production line "certified" by DSCC to produce
MIL-PRF-38534 product. Then, they must have a part specification
(Standard Military Drawing, SMD) written for the specific part they will
sell. Successful testing to the electrical specifications of the SMD and
the overall quality and reliability program defined in MIL-PRF-38534, to
the Class K level, then allows them to mark and sell DC to DC converters
with the SMD part number and the Class K "brand". Though a relatively
large number of vendors are certified to make Class H and Class K
MIL-PRF-38534 Hybrids, only one source (Crane Interpoint Corporation)
has completed the entire program, through SMD and qualification, for
Class K DC to DC Converters. Appendix A contains every Class K, DC to DC
power converter readily available for procurement. Table 2 describes the
available Class K DC to DC converters according to their input voltage
and output power. The relatively small number of products that have
passed through the entire QML-K process often lead NASA projects to
buying non-SMD part numbers to satisfy their needs. The dual approach of
using standard and non-standard parts in space systems, has at times
reduced the use of the few Class-K part numbers that are available and
directs NASA procurement dollars away from investment in qualifying new
part numbers.

**Table 1:** DSCC Certified Vendors for MIL-PRF-38534 Product

  ----------------------------------- -----------------------------------
  Advanced Analog IR                  Aeroflex Microelectronic Solutions

  Agilent Technologies                Analog Devices Incorporated

  Apex Microtechnology                Austin Semiconductor, Inc.

  BAE Platform Solutions              BI Technologies Corporation

  Boeing Defense and Space Group      C-MAC Microcircuits Limited

  CMC Electronics Cincinnati          CMC Electronics Incorporated

  Cougar Components                   Crane Interpoint

  DDC Ireland LTD.                    Data Device Corporation

  Datel Incorporated                  EMS Technologies Incorporated

  Hytek Microsystems Incorporated     International Rectifier Corporation

  Interpoint Taiwan Corporation       Lockheed Martin Missiles and Fire
                                      Control

  M.S. Kennedy Corporation            MPC Products Corporation

  Micro Networks Company              Micro-Precision Technologies, Inc.

  Micropac Industries, Incorporated   Natel Engineering Company, Inc.

  National Hybrid, Incorporated       REMEC Components -- Palm Bay

  REMEC Incorporated                  Raytheon Systems Limited

  Satcon Electronics                  Sensitron Semiconductor

  Solitron Devices, Incorporated      Teledyne Electronic Technologies

  VPT/Delta                           Warner Robins ALC/LYP

  White Electronic Designs            
  Corporation                         
  ----------------------------------- -----------------------------------

The "off-the-shelf" certification, radiation data and electrical
characterization that comes with MIL-PRF-38534, Class K devices
dramatically shortens procurement lead time and lowers cost as compared
to lead time and cost for comparable devices that are not sold within
the mil-spec system. To buy a comparable part outside of the mil-spec
system using a Source Control Drawing (SCD) or to buy a new design
within the mil-spec system by creating a new SMD requires a nominal 26
weeks for creating and coordinating the drawing and finalizing the
design parameters and another 60 weeks for manufacturing. An 18 to 24
month lead time for a DC to DC converter is usually considered
problematic in the context of a flight mission schedule. Many space
programs don't have the luxury to incur a long-lead procurement for such
a critical part. Projects that can take advantage of off-the-shelf,
Class K part numbers can realize a great schedule advantage over those
who decide to, or must, create an SCD or SMD for their purchase.

**Table 2:** Interpoint Class K DC to DC Converter Types

+-----------------+-----------------+------------------+---------------+
| **Family Name** | **Vin (VDC)**   | **Vout (VDC)**   | **Power**     |
+-----------------+-----------------+------------------+---------------+
| SLH             | 28              | Single: 3.3, 5,  | 1.5 Watts     |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+
| SMFL            | 28              | Single: 3.3, 5,  | 65 Watts      |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+
| SMFLHP          | 28              | Single: 3.3, 5,  | 100 Watts     |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+
| SMHF            | 28              | Single: 3.3, 5,  | 15 Watts      |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+
| SMSA            | 28              | Single: 3.3, 5,  | 5 Watts       |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+
| SMTR            | 28              | Single: 3.3, 5,  | 30 Watts      |
|                 |                 | 12, 15           |               |
|                 |                 |                  |               |
|                 |                 | Dual: ±5, ±12,   |               |
|                 |                 | ±15              |               |
+-----------------+-----------------+------------------+---------------+

Cost and performance are also big drivers when embarking on a new
SCD/SMD-based procurement. Past experience shows costs to run from
\$200K to \$500K for this type of effort depending on the hybrid
complexity and technical support required during design and
qualification testing; the cost and lead-time for a printed circuit
board (discrete) design and a custom hybrid power converter build can be
about the same. It is quite common that existing designs are modified or
"tweaked" to meet the electrical performance specifications in the new
SCD. The impact of the modification on electrical performance over a
wide range of operating conditions may be logistically difficult to
determine and again, cost prohibitive. The impact the change will have
on the long term reliability of the overall part and primary failure
modes may be practically impossible to understand within the timeframe
of the project.

**[Future Needs]{.underline}**

The market for commercial, portable electronics produces a high demand
for low voltage and low power microcircuits. Reduced transistor feature
size is a key enabler allowing both existing circuits to occupy a
smaller physical space on the chip and the addition of new features with
no increase in footprint. Lower voltage thresholds enable higher
switching frequencies which extends the capability of data and signal
processors. The space industry benefits from this technological trend by
being able to pack increased functionality and complexity into limited
mass and volume allocations. An example of this concept is shown in
Figure 2. Another example is the trend toward more data processing
functionality in flight instruments rather than accomplishing data
processing primarily on the ground. With this increased complexity and
operating frequency comes an increase in the circuit power dissipation.

![](media/image5.jpeg){width="6.293055555555555in"
height="3.901388888888889in"}

**Figure 2:** Following the trend in semiconductor density, it is
feasible to reduce spacecraft C&DH electronics significantly, eventually
achieving a "spacecraft on a chip" implementation.

As described above, semiconductor technology and system engineering
trends are expected to continue to change critical operational
requirements for DC to DC converters for future spaceflight hardware.
Newly discovered failure mechanisms such as those associated with ELDRS
or trapped charges attendant to nuclear events that constitute "Van
Allen belt-like" conditions, are also driving new test and performance
requirements. Even though low voltage electronics would appear to reduce
the payload's heat, the very high switching speeds drive up overall
power and thermal dissipation. Very low noise becomes critical in low
voltage circuits and will cause the need for closer examination of
maximum ripple specifications (1% ripple of a 2V output is only 10 to 20
millivolts).

Modularity is increasingly being considered as a strategy to combat a
lack of market share and the continual re-development of power supply
components for a wide range of system topologies (Figure 3). Versatile
electrical and mechanical interfaces that integrate easily into
higher-level assemblies enable design reuse. The bus and payload power
converter must be able to work in a complementary fashion to provide all
the required voltage levels and regulation while maintaining stability
and low system noise. Technologies such as programmability, increased
radiation tolerance (both total ionizing dose to a minimum level of 100
kRads(Si) and single event effects with a minimum upset resistance to
particles of 37 MeV), modularity and increased volumetric efficiency
(W/m^3^) have all been identified as key enabling features for future
high performance, highly reusable systems.

![](media/image6.png){width="3.9555555555555557in"
height="2.0069444444444446in"}

> **Figure 3:** Family of power elements

**[Conclusions]{.underline}**

This overview broadly discusses the needs driving the use of DC to DC
converters in space systems, existing and preferred procurement
strategies, and performance and assurance issues associated with DC to
DC converter use. It also touches on the size of the DC to DC converter
component of the aerospace electronic parts industry and availability of
space grade product. This paper demonstrates the need for more
manufacturers, as there is currently only one source for off-the-shelf,
space-grade product (Crane Interpoint). The demand for new, lower
voltage levels while improving reliability and immunity to strenuous
aerospace environments creates a high entrance barrier to new vendors
and slows the increase in new space-grade part numbers from certified
shops. With the low number of available Class K qualified part numbers
and MIL-PRF-38534-certified vendors, flight projects continue to face
long lead times and higher costs in order to obtain flight-ready parts
via SCD's or new SMD's. Working with the qualified suppliers giving them
the necessary requirement needs and information before project
procurement cycles begin is the key to reducing this problem.

**APPENDIX A**

  ---------------------- ---------- -------------------- -----------------
  **K Level                                              
  Certified/Qualified                                    
  Microcircuit DC/DC                                     
  Converters for Space                                   
  Applications**                                         

                                                         

  **DSCC#**              **DATE**   **MANUFACTURER**     **PART \#**

  5962L0052601KXA        12/16/02   Interpoint           SLH2805S

  5962L0052601KXC        12/16/02   Interpoint           SLH2805S

  5962R0052601KXA        12/16/02   Interpoint           SLH2805S

  5962R0052601KXC        12/16/02   Interpoint           SLH2805S

                                                          

  5962L0052701KXA        2/7/01     Interpoint           SLH2812S

  5962L0052701KXC        2/7/01     Interpoint           SLH2812S

  5962R0052701KXH        2/7/01     Interpoint           SLH2812S

  5962R0052701KXC        2/7/01     Interpoint           SLH2812S

                                                          

  5962L0052801KXA        12/16/02   Interpoint           SLH2815S

  5962L0052801KXC        12/16/02   Interpoint           SLH2815S

  5962R0052801KXA        12/16/02   Interpoint           SLH2815S

  5962R0052801KXC        12/16/02   Interpoint           SLH2815S

                                                          

  5962R0150102KXA        10/26/01   Interpoint           SMTR283R35

  5962R0150102KXC        10/26/01   Interpoint           SMTR283R35

  5962R0150102KZA        10/26/01   Interpoint           SMTR283R3SF

  5962R0150102KZC        10/26/01   Interpoint           SMTR283R3SF

                                                          

  5962R0250401KXA        12/11/01   Interpoint           SLH2805D

  5962R0250401KXC        12/11/01   Interpoint           SLH2805D

                                                          

  5962L0251002KXA        1/15/03    Interpoint           SMHF283R3S

  5962L0251002KXC        1/15/03    Interpoint           SMHF283R3S

  5962R0251002KXA        1/15/03    Interpoint           SMHF283R3S

  5962R0251002KXC        1/15/03    Interpoint           SMHF283R3S

  5962L0251002KZA        1/15/03    Interpoint           SMHF283R3SF

  5962L0251002KZC        1/15/03    Interpoint           SMHF283R3SF

  5962R0251002KZA        1/15/03    Interpoint           SMHF283R3SF

  5962R0251002KZC        1/15/03    Interpoint           SMHF283R3SF

                                                          

  5962L9160102KXA        10/2/03    Interpoint           SMHF2815S

  5962L9160102KXC        10/2/03    Interpoint           SMHF2815S

  5962R9160102KXA        10/2/03    Interpoint           SMHF2815S

  5962R9160102KXC        10/2/03    Interpoint           SMHF2815S

  5962L9160102KZA        10/2/03    Interpoint           SMHF2815SF

  5962L9160102KZC        10/2/03    Interpoint           SMHF2815SF

  5962R9160102KZA        10/2/03    Interpoint           SMHF2815SF

  5962R9160102KZC        10/2/03    Interpoint           SMHF2815SF

                                                          

  5962L9161402KXA        10/14/03   Interpoint           SMHF2815D

  5962L9161402KXC        10/14/03   Interpoint           SMHF2815D

  5962R9161402KXA        10/14/03   Interpoint           SMHF2815D

  5962R9161402KXC        10/14/03   Interpoint           SMHF2815D

  5962L9161402KZA        10/14/03   Interpoint           SMHF2815DF

  5962L9161402KZC        10/14/03   Interpoint           SMHF2815DF

  5962R9161402KZA        10/14/03   Interpoint           SMHF2815DF

  5962R9161402KZC        10/14/03   Interpoint           SMHF2815DF

                                                          

  5962L9213902KXA        6/26/00    Interpoint           SMHF2805S

  5962L9213902KXC        6/26/00    Interpoint           SMHF2805S

  5962R9213902KXA        6/26/00    Interpoint           SMHF2805S

  5962R9213902KXC        6/26/00    Interpoint           SMHF2805S

  5962L92130902KZA       6/26/00    Interpoint           SMHF2805SF

  5962L92130902KZC       6/26/00    Interpoint           SMHF2805SF

  5962R92130902KZA       6/26/00    Interpoint           SMHF2805SF

  5962R92130902KZC       6/26/00    Interpoint           SMHF2805SF

                                                          

  5962L9214402KXA        11/6/03    Interpoint           SMHF2812D

  5962L9214402KXC        11/6/03    Interpoint           SMHF2812D

  5962R9214402KXA        11/6/03    Interpoint           SMHF2812D

  5962R9214402KXC        11/6/03    Interpoint           SMHF2812D

  5962L9214402KZA        11/6/03    Interpoint           SMHF2812DF

  5962L9214402KZC        11/6/03    Interpoint           SMHF2812DF

  5962R9214402KZA        11/6/03    Interpoint           SMHF2812DF

  5962R9214402KZC        11/6/03    Interpoint           SMHF2812DF

                                                          

  5962L9306802KXA        4/26/00    Interpoint           SMTR2805S

  5962L9306802KXC        4/26/00    Interpoint           SMTR2805S

  5962R9306802KXA        4/26/00    Interpoint           SMTR2805S

  5962R9306802KXC        4/26/00    Interpoint           SMTR2805S

  5962L9306802KZA        4/26/00    Interpoint           SMTR2805SF

  5962L9306802KZC        4/26/00    Interpoint           SMTR2805SF

  5962R9306802KZA        4/26/00    Interpoint           SMTR2805SF

  5962R9306802KZC        4/26/00    Interpoint           SMTR2805SF

                                                          

  5962L9306902KXA        6/21/00    Interpoint           SMTR2812S

  5962L9306902KXC        6/21/00    Interpoint           SMTR2812S

  5962R9306902KXA        6/21/00    Interpoint           SMTR2812S

  5962R9306902KXC        6/21/00    Interpoint           SMTR2812S

  5962L9306902KZA        6/21/00    Interpoint           SMTR2812SF

  5962L9306902KZC        6/21/00    Interpoint           SMTR2812SF

  5962R9306902KZA        6/21/00    Interpoint           SMTR2812SF

  5962R9306902KZC        6/21/00    Interpoint           SMTR2812SF

                                                          

  5962L9307002KXA        6/22/00    Interpoint           SMTR2815S

  5962L9307002KXC        6/22/00    Interpoint           SMTR2815S

  5962R9307002KXA        6/22/00    Interpoint           SMTR2815S

  5962R9307002KXC        6/22/00    Interpoint           SMTR2815S

  5962L9307002KZA        6/22/00    Interpoint           SMTR2815SF

  5962L9307002KZC        6/22/00    Interpoint           SMTR2815SF

  5962R9307002KZA        6/22/00    Interpoint           SMTR2815SF

  5962R9307002KZC        6/22/00    Interpoint           SMTR2815SF

                                                          

  5962L9308902KXA        5/21/01    Interpoint           SMSA2812D

  5962L9308902KXC        5/21/01    Interpoint           SMSA2812D

  5962R9308902KXA        5/21/01    Interpoint           SMSA2812D

  5962R9308902KXC        5/21/01    Interpoint           SMSA2812D

  5962L9309002KXA        7/10/01    Interpoint           SMSA2815D

  5962L9309002KXC        7/10/01    Interpoint           SMSA2815D

  5962R9309002KXA        7/10/01    Interpoint           SMSA2815D

  5962R9309002KXC        7/10/01    Interpoint           SMSA2815D

                                                          

  5962L9309202KXA        2/6/01     Interpoint           SMSA2805S

  5962L9309202KXC        2/6/01     Interpoint           SMSA2805S

  5962R9309202KXA        2/6/01     Interpoint           SMSA2805S

  5962R9309202KXC        2/6/01     Interpoint           SMSA2805S

                                                          

  5962L9309302KXA        10/23/00   Interpoint           SMSA2812S

  5962L9309302KXC        10/23/00   Interpoint           SMSA2812S

  5962R9309302KXA        10/23/00   Interpoint           SMSA2812S

  5962R9309302KXC        10/23/00   Interpoint           SMSA2812S

                                                          

  5962L9309402KXA        2/6/01     Interpoint           SMSA2815S

  5962L9309402KXC        2/6/01     Interpoint           SMSA2815S

  5962R9309402KXA        2/6/01     Interpoint           SMSA2815S

  5962R9309402KXC        2/6/01     Interpoint           SMSA2815S

                                                          

  5962R9316302KTA        6/21/02    Interpoint           SMFL2805SW

  5962R9316302KTC        6/21/02    Interpoint           SMFL2805SW

  5962R9316302KUA        6/21/02    Interpoint           SMFL2805SV

  5962R9316302KUC        6/21/02    Interpoint           SMFL2805SV

  5962R9316302KXA        6/21/02    Interpoint           SMFL2805S

  5962R9316302KXC        6/21/02    Interpoint           SMFL2805S

  5962R9316302KYA        6/21/02    Interpoint           SMFL2805SY

  5962R9316302KYC        6/21/02    Interpoint           SMFL2805SY

  5962R9316302KZA        6/21/02    Interpoint           SMFL2805SZ

  5962R9316302KZC        6/21/02    Interpoint           SMFL2805SZ

  5962R9319302KTA        6/21/02    Interpoint           SMFL2815DW

  5962R9319302KTC        6/21/02    Interpoint           SMFL2815DW

  5962R9319302KUA        6/21/02    Interpoint           SMFL2815DW

  5962R9319302KUC        6/21/02    Interpoint           SMFL2815DW

  5962R9319302KXA        6/21/02    Interpoint           SMFL2815D

  5962R9319302KXC        6/21/02    Interpoint           SMFL2815D

  5962R9319302KYA        6/21/02    Interpoint           SMFL2815DY

  5962R9319302KYC        6/21/02    Interpoint           SMFL2815DY

  5962R9319302KZA        6/21/02    Interpoint           SMFL2815DZ

  5962R9319302KZC        6/21/02    Interpoint           SMFL2815DZ

                                                          

  5962L9852901KXA        2/7/01     Interpoint           SLH2815D

  5962L9852901KXC        2/7/01     Interpoint           SLH2815D

  5962R9852901KXA        2/7/01     Interpoint           SLH2815D

  5962R9852901KXC        2/7/01     Interpoint           SLH2815D

                                                          

  5962L9955601KXA        8/4/00     Interpoint           SLH2812D

  5962L9955601KXC        8/4/00     Interpoint           SLH2812D

  5962R9955601KXA        8/4/00     Interpoint           SLH2812D

  5962R9955601KXC        8/4/00     Interpoint           SLH2812D
  ---------------------- ---------- -------------------- -----------------

###### APPLICABLE DOCUMENT SOURCES

1)  "Capacitor Applications In Switching Power Supplies", J. Maxwell,
    March 15, 1995, sponsored by IEEE.

2)  "Comparison of PWM Zero Voltage Switching DC-DC Converters with
    Output Isolation", J. Qian, October 10, 1995, sponsored by IEEE.

3)  "Test and Evaluation of Load Converter Topologies Used in SSF Power
    Management and Distribution DC Test Bed", R.C. Lebron, August 1991,
    sponsored by IECEC.

4)  "A New Three-Phase AC-DC Zero Voltage Switching Isolated Converter
    Operating In DCM", Y.V. Panov, October 10, 1995; sponsored by IEEE.

5)  "DV/DT-Current Handling Capabilities of SMPS MLC Capacitors", S.P
    Cygan, March 16, 1992, sponsored by IEEE.

6)  "Subsystem Integration For Efficient Power Flow in 21^st^ Century
    Airlifters", D.K. Lindner, September 1, 1999, sponsored by
    AFRL-SR-BL.

7)  *"Understanding Reliability In Commercial Power Converters"*, A.
    Simopoulos. March 1993, sponsored by Hearst Business Publications.

8)  "Multikilowatt Power Electronics Development For Spacecraft", D.K.
    Decker, August 1991, sponsored by IECEC.

9)  "Multilevel Converters - A New Breed Of Power Converters", J.S. Lai,
    October 10, 1995, sponsored By IEEE.

10) "Improving The Frequency Response of Ceramic Dielectrics For High
    Power Applications In Power Electronic Converters", C. Campbell,
    December 1996, sponsored by IEEE.

11) *"Radiation Effects on DC-DC Converters",* J.O. Attia, August 1,
    1999, sponsored by Prairie View Agricultural and Mechanical College.

12) *"Application Of IIIV Power Devices For DC/DC Power Conversion",* S.
    Ajram, January 4, 1996, sponsored by Universite des Sciences et
    Technologies de Lille.

13) "Frequency-Based Load Sharing In Current-Mode-Controlled Buck
    Converters", J.E. Moore, March 1 1999, sponsored by the Naval
    Postgraduate School.

14) "Enhancing Reliability Of Board Mounted Power Modules Through
    End-To-End Process Improvement", R.J. Brandt, March 16, 1992,
    sponsored by IEEE.

15) "*Effect Results for Microelectronics"*, Martha O'Brien & Christina
    Seidleck of Raytheon Sys. Lanham, MD, Kenneth Label, Donald Hawkins,
    Janet Barth, Robert Reed & Cheryl Marshall of NASA/GSFC, Greenbelt,
    MD, Jim Howard & Hak Kim of J&T Seabrook, MD. 1999 NSREC Data
    Workshop.

16) "Radiation Testing Results of COTS Based Space Microelectronics",
    1999 NSREC Data Workshop.

17) "The Effects of Space Radiation and Burn-In on Plastic Encapsulated
    Semiconductors", 1999 NSREC Data Workshop.

18) "Radiation Evaluation of Plastic Encapsulated Transistors and
    Microcircuits for Use in Space Applications", 1999 NSREC Data
    Workshop.

19) *"Device SEE Susceptibility Update"*, 1996-1998, 1999 NSREC Data
    Workshop

20) IEEE Nuclear Science, Dec 2000, Volume 47, Number 6, Part II of IV
    Parts, Page 2039 & 2045.

21) IEEE Nuclear Science, Dec 2000, Volume 47, Number 6, Part I of IV
    Parts, Page 1872 & 1879.

22) NSREC Data Workshop, 2000, Page 6, 32, 53, 100, 106 & 123.

23) IEEE NSREC Short Course, 2000, Section IV.

24) Proceedings European Space Components Conference ESCCON 2000:

    a.  "Very Fine Line Technology for MCM-C Manufacturing Evaluation
        and Industrialization", O. Puig, CNES, France and D. Samson,
        Matra Marconi Space, France, P 39.

    b.  "Power Modules: A Novel Approach to Achieve Compact Solutions
        for Complex Power Conditioning Circuits", M. Perusini, and G.
        Tommaso, Alenia Aerospazio S.p.A., Italy, P45.

    c.  "Theoretical and Empirical Verification of the Stress
        Distribution in Stacked Ceramic Capacitors for Space
        Applications", T. Kraft, Th. Gaul, R, Loffler, and R, Theis,
        BoschTelecom GmbH, Germany, P71.

    d.  "Supercapacitors: Applications and Requirements", H. Barde, MMS,
        France P 79

    e.  "A Structured Procedure For Assessing the Suitability of
        Commercial Components for Space Applications", P109, 115, 121,
        125, 131, 143, 151, 277.

    f.  *"Temperature Uprating Study on Use of Commercial Components for
        Space Applications"*, Ph. Lay, C. Aicardi, B. Pasquier, P.
        Prodhomme, P. Carton, and P. LeBlanc, P.Lab. Central des
        Industries Electriques, France; CNES, France; Thomson CSF-TTM,
        France, Matra Marconi Space, France, P115.

    g.  *"Establishment of Derating Rules and Worst Case Analysis
        Figures for EEE Components"*, L. Cosqueric, P. LeBlanc, G.
        Salveterra, L. Toudret, Matra Marconi Space, France, P121.

    h.  "Procurement of Catalogue Hybrid DC/DC Converters for Various
        Space Projects", T. Liebler, B. Stradler, Bosch Telecom GmbH,
        Germany, P131.

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