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Info Source	QML Manufacturer?	Type	Problem Category	Link to more info	Comments
Non-NASA			Misapplication? Quality?		Date: 1994 Converter failed during thermal vacuum testing of the spacecraft due to either: 1) Overheating of the converter lead to thermal instability of the rectifier Schottky diode on the 5 V output side of the transformer. OR 2) an open circuit due to a solder joint failure in the diode. The open circuit would lead to an arc forming between the wire and the edge of the diode. Material melted by the arc could form a short that would remain even after the diode cooled to room temperature. Both scenarios lead to thermal overstress of the converter. (af)
Non-NASA	Yes	28 Vin, Triple, 5V, ±15V, 30W	Element Failure – cracked capacitors and solder joints		Date: 10/95 One sample converter from two vendors was submitted to a preliminary assessment test sequence (thermal shock, vibration, mechanical shock). Both devices showed signs of damage after the test, with the most severe damage shown in the form of detached and cracked capacitor stacks, and cracked solder joints to pin. The project recommendation was to proceed with vendor 2.
Non-NASA			Element Failure – package bottom surface not flat		Date: 1995 Package bottom was not flat causing ineffective installation. (af)
Non-NASA			Insufficient Characterization		Date: 1995 Converter overly noisy for use with A/D converter application. (af)
JPL	No	28Vin, 5Vout	Unexpected Electrical Behavior – By Design		Date: 7/11/96, Seawinds Converter would not start if the input was not first returned to zero. Analysis showed insufficient internal design margin. Report Z23378. Contact: Gary Bivins
Non-NASA	Yes	28 Vin, Triple, 5V, ±15V, 30W	Quality – low bond pull, Performance – TCycle test failures, incoming		Date: May 1997 During environmental testing (endurance, temperature cycling, vibration) and DPA of commercial grade converters. Numerous anomalies reported; · Electrical test failure (device non-functional) and PIND failure during incoming screening · Catastrophic failure during endurance test · Thermal cycled device failed leak test after 200 cycles and failed electrical test after 500 cycles · DPA showed various wires below pull test limits and capacitors below die shear limit
Non-NASA	Yes	Triple	Quality – PIND failures, low bond pull, Performance – Life test failures		Date: May 1997 During environmental testing (endurance, temperature cycling, vibration) and DPA of commercial grade converters. Numerous anomalies reported; · PIND failure during incoming screening · Electrical test failure during endurance test device out of spec at 500hrs and 1000hrs test points, and total failure at 2000hrs) · Electrical test failure (isolation) after vibration · DPA showed various wires below pull test limits and capacitors below die shear limit
Non-NASA	Yes	28 Vin, 5V Dual, 15W, 28 Vin, 15V Dual, 15W	Quality – leak test and bond pull discrepancy		Date: Sept. 19, 1997 leak test failures associated with cracked seals (possible handling problem) and one low pull strength wire bond.
Non-NASA	Yes	28 Vin, 5V Single, 15W, 28 Vin, 5V Dual, 15W, 28 Vin, 15V Dual, 15W	Quality – leak test and die shear discrepancy		Date: Sept 15, 1997 leak test failures associated with cracked seals (possible handling problem) and some low values at die shear test
Non-NASA	Yes	28 Vin, 5V Single, 15W, 28 Vin, 15V Dual, 15W	Radiation – performance reduction		Date: Sept 1, 1997 Test showed devices remain functional upto 50krads but with small increase in output voltage and approx. 20% reduction in efficiency at 16 V input voltage.
Non-NASA	Yes	28 Vin, 5V Single, 15W, 28 Vin, 5V Dual, 15W, 28 Vin, 15V Dual, 15W	Radiation – device failure		Date: Sept 1, 1997 Test showed that the 15V Dual and the 5V Single devices remain functional up to 49krads but with reduction in output voltage and efficiency, and increase in input current. However the 5V Dual device lost functionality at 5.5krad. After 7.5hrs annealing at room temperature device had shown some recovery (device functional at 28 V and 40V but not at 16 V). This anomaly was investigated in analysis RA0102, where device was subjected to radiation at lower dose rate. Device again lost functionality at 3-4 krads and did not recover after 53-hrs room temperature anneal (biased). However after high temperature bake (27hrs @ 100degC) device returned to full functionality.
JPL	No	28Vin, 5Vout	Unexpected Electrical Behavior		Date: 12/12/97, MPL Due to the onset of oscillations, a fuse was blown during box-level burn-in. The ambient temperature was 80C and the loading was “light”. Report P1004. Contact: Gary Bivins
Non-NASA	Yes	120Vin, 50W	Performance – design margin, Quality – lack of Process Control, Quality Control		Date: 1996-1997 encountered many problems particularly for 120 V types: · Major technical problems – the design of the new hybrids had not been sufficiently investigated and verified. Insufficient margin had been included in the design to cope with variation of the characteristics of add-on elements. · Serious manufacturing difficulties – lack of process control, with processes often introduced prior to verification and qualification. Processes not very repeatable with the quality of the final product being very operator dependant · Deficiencies in quality assurance – problems are solved with a view to maintaining production without ensuring problem does not re-occur. NCR process is ineffective. Implementation of new quality procedures was poor. · Bad management;- procurement of add-on parts and materials poorly controlled; program planning ineffective; poor reporting resulted in lack of visibility for customer. All these factors contributed to innumerable deficiencies being encountered with the parts (up to July 98 at least 43 NCR’s had been issued for this procurement), leading to major delays (up to one year) with the delivery of parts
JPL	Yes	28Vin, 3.3Vout	Incorrect Mounting onto chassis		Date: 4/6/98, Seawinds During EMC testing, the device failed the CE and isolation tests. The hybrid case was not isolated from the chassis. Report: Z46807. Contact: Gary Bivins
JPL			Packaging – Workmanship		Date?: Mars98 Workmanship failures. Parts eventually assembled at JPL Contact: Gary Bivins
Non-NASA			Quality		Date: 1998 Failure during thermal vacuum testing caused a system intermittent failure. System-level failure effects analysis pointed to the DC/DC converter as the problem. Damage and workmanship discrepancies, such as component interference, presence of metallic debris and lack of conformal coating, found inside the converter support a conclusion that this failure was created by a short inside the DC/DC Converter.
JPL	Yes	28Vout, +/-15Vin, 5Vin, Triple, 30W	Element Evaluation, Element Performance		Date: 8/28/98, Jason Failure of multiple output capacitors during Hybrid-level life test. Catastrophic failure resulted. Contact: Gary Bivins
Non-NASA			In-Flight failure		Date: 1999 DC/DC Converter on A side failed catastrophically; no output. Lack of blown fuse on the input side indicates that the front end did not have a short. (af)
Non-NASA	Yes	Various (28 V and 120V inputs)	Quality – unresponsive to NCR’s		Date: May 1999 Many problem encountered in getting the vendor to comply with requested changes in manufacturing and quality procedures that had been identified in order to achieve high rel. product.
JPL	Yes	28Vin, +/-15Vout, dual, 30W	Element Evaluation, Element Performance		Date: 6/17/99, SIRTF Catestrophic failure due to failed stacked capacitor on the input during hybrid-level life test. Contact: Gary Bivins
JPL	Yes		Element Evaluation, Element Performance		Date: 1/10/00. GRACE, GALEX PWM controller chip Unitrode 1824 was found to be unstable in the circuit when the operating temperature was above 85ºC causing a reduction in switching frequency. Converter Vout found to droop 200mV to 400mV for low input voltage conditions with full loads. When these converters were power derated (to 75%) for Toperation > 85ºC the performance returned to specified values. Internal design changes were made to “re-center” the switching frequency. Element evaluation is a standard process that can be used to discover internal part limitations or inadequacies prior to their installation in the hybrid. Contact: David Gerke
Non-NASA	Yes		Other – failure at burn-in		Date: March 2000 The DC/DC Converter exhibited catastrophic failures during / after Burn-in. Problem was attributed to wrong loading of the outputs of this converter (zero load inhibits voltage regulation which causes the output voltages to rise beyond limits, thus destroying the capacitors across the output lines). The conclusion at that time was that nothing else than the output capacitors had seen the overvoltage and a repair by the vendor replacing the affected capacitors and re-testing the DC-DC converters was performed. However after rework, parts exhibited some electrical isolation failures, after burn-in, between input and output (which should normally be isolated via the internal transformer). Failure analysis showed totally burnt bobbins. This indicated that the conclusion after the first burn-in failure (electrical over-voltage at output would only affect the components at the output side) had not been backed up by a good failure analysis, and was incorrect. It was evident that during the rework to replace the capacitors, the transformers had not been checked. In fact, it is now also LAA's understanding that when the capacitors broke by the over-voltage, this would produce a low resistive path (short circuit) which then overstressed the DC/DC converter (transformer, possibly other components as well). After these failures the lot was returned to the vendor to be replaced by a new lot.
JPL and GSFC	Yes	28Vin, 30W	Packaging – Design, Process, Radiation – Device Upset	Element Stuck to Lid	Date: 3/16/00 SIRTF at JPL, Image and Gravity Probe B at GSFC Lid stuck to internal devices causing solder joint failure when the lid deflected in a vacuum, stiffener added by users. Pulse width modulator upset caused failure of diode. PWM circuitry changed, diode changed.
JPL			Packaging - Design, Process, Performance – electrical w/temp		Date?, GALEX, Grace, MIRO Shorted capacitors due to excess solder trapped underneath them. Adhesion failure caused an electrical interconnect failure. Burn-in results showed electrical efficiency not to spec over all temp ranges. Conductive epoxy used on substrate caused isolation failures. Contact: Gary Bivins
JPL			Element Failure - Capacitors		Date? GALEX, TES Capacitor failures linked to life test failures. Contact: Gary Bivins
LaRC	Yes		Element Selection – Tin plating		Date? Concerns about optocouplers, tin whiskers. Pre-cap found need for significant rework Contact: John Pandolf
LaRC	Yes	28Vin to 15Vout (SCD spec)	In Flight Failure - Unknown		Date: 2000 CERES (EOS) Loss of regulation after 7 months in service. Loss of CTR in optocoupler providing feedback. Determined to NOT be radiation related. Contact: John Pandolf
JPL	Yes	28Vin, 15Vout, Single, 65W			Date: 4/29/00, SIRTF Catestrophic failure during thermal vacuum testing. Report Z72922. Contact: Gary Bivins
JSC	No	120Vin, 12Vout, Single	Element Failure – MOSFET		Date? SVS LDC 9747, 28Vin/12Vout Shorted MOSFET Contact: Stephen Trifilo
Non-NASA			Quality		Date: 2001 Root cause traced to vendor workmanship issues. Vendor implemented process changes to improve manufacture of device and independent review team approved process changes. (af)
JSC	No	120Vin, 12Vout, Single	Element Failure – Thermal Switch		Date 2001 SVS LDC 9744, 120Vin/12Vout, Failed Thermal Switch Contact: Stephen Trifilo
JSC	No	120Vin, 5Vout, Single	Element Failure – Shorted Diode		Date 2001 SVS LDC 9747, 120Vin/5Vout, Shorted Surface Mount Diode Contact: Stephen Trifilo
JSC	No	28Vin, 12Vout, Single	Element Failure – Shorted Capacitor		Date 2001 SVS LDC9803, 28Vin/12Vout, Shorted Multilayer Ceramic Capacitor, Surface Mount Contact: Stephen Trifilo
JSC	No	120Vin, 5Vout, Single	Element Failure – Shorted Capacitor		Date 2001 SVS LDC9751, 120Vin/5Vout, Shorted Multilayer Ceramic Capacitor, Surface Mount Contact: Stephen Trifilo
JSC	No	120Vin, 12Vout, Single	Element Failure – Shorted Capacitor		Date 2001 SVS 120Vin/12Vout, Shorted Multilayer Ceramic Capacitor, Surface Mount Contact: Stephen Trifilo
GSFC	Yes		Element Selection – non-high rel, Screening – not correct for part type or application conditions, Element Failure – film capacitor		Date: Jan 3, 2001-GLAS Non-established reliability stacked film capacitors used in the converter experienced significant physical changes due to the method in which they were screened, installed and applied. The method used to screen the parts was suspected of aging the parts. The methods used during hybrid build up after the capacitors are installed inadvertently removed material from the parts as well as added foreign material to them. The electrical circuit used applied a signal to the capacitors with a pulse component (100’s of kHz) which was not a screening condition. These factors lead to a very high failure rate for these capacitors after they were installed. Test data to resolve new screening methods and the resulting part reliability was not generated. Contact Mike Sampson, Henning Leidecker
JPL	Yes	28Vin, +/-12Vout, 80W	Unexpected Electrical Behavior		Date: 2/5/01, EMLS No turn-on with a 2.5S load was encountered. Needed to use an external turn-on delay circuit. See JPL report Z70457. Contact: Gary Bivins
JPL	Yes	5V Single	Testing - Incomplete		Date: 3/9/01 No Group C or Subgroup-2 life test performed. Contact: Gary Bivins
GSFC	Yes	28Vin, 15Vout, Dual, 65W	TBD		Date: 5/16/01, HST, STIS Side 1 In flight, the instrument current dropped from its nominal current to zero between two consecutive telemetry samples. In-flight testing showed that there was a short between the 28Vin and the Return pins on the STIS input. No chassis current was observed. A analysis of the possibility of the parts in the vicinity causing the short was done. The best guess was that tantalum capacitors outside of the converter failed. It is not known if the converter, with integral filter, overstressed the capacitors.
JPL	Yes	28Vin, 5Vout, Single, 1.5W	Element malfunction		Date: 6/21/01, GRACE The output rose to 10.8V during post vibration electrical test due to failure of the internal PWM device. The PWM chip malfunctioned causing the converter to operate open loop. The failure was confirmed by IPT, and then the chip began behaving normally. No visual defects were observed. The cause of the chip malfunction was not determined, but not believed to be a design problem. See report Z70090. Contact: Gary Bivins
JPL	Yes	28Vin, 28Vout, Single, 80W	Unexpected Electrical Behavior – By Design		Date: 7/14/01, TES Oscillation at turn-on encountered during box functional test. The device could not start up with a 75uF load. 120uF was added at the input to resolve the problem. Report Z72081. Contact: Gary Bivins
JPL	Yes	28Vin, 3.3Vout, Single, 23W			Date: 10/29/01, MET Cracked substrate during Hybrid-level life testing due to test fixture. Report Z72540. Contact: Gary Bivins
JPL	Yes	28Vin, 5Vout, Single, 30W	Life Test Failure		Date: 10/29/01, MER Cracked epoxy attach for a capacitor encountered during life test. See JPL report Z72540. Contact: Gary Bivins
JPL	Yes	28Vin, 5Vout, Single, 5W	Element Failures – life test failure		Date: 10/29/01, MER Input capacitors failed during finished unit life testing. The capacitor lot was indicted. See JPL report Z72540. Contact: Gary Bivins
JPL	Yes	28Vin, 15Vout, Single, 65W	EMC Limit Failure		Date: 4/24/02, Cloudsat EMC limit failure encountered during EMC CS02 testing. A bypass capacitor was needed between the chassis and the i/o returns to reject CM noise. A filter was also needed in front of the IPT filter. Report number is Z75296. Contact: Gary Bivins
JPL	Yes	28Vout, 5Vin, Single, 5W	TBD		Date: 5/22/02, GRACE A suspected in-flight failure. See report Z76559. Contact: Gary Bivins
JPL	Yes	28Vin, +/-15Vout, dual, 30W	Unexpected Electrical Behavior – Oscillation and CM Noise		Date: 5/6/02, Cloudsat The synchronization pin was left open and oscillation was encountered. A bypass capacitor between chassis and the i/o returns was needed to reject CM noise. See JPL report Z75643. Contact: Gary Bivins
MSFC	No	120Vin, +/-12Vout, 36W; 120Vin, +/-15Vout, 37W; 120Vin, 5Vout, 75W	Packaging Quality		Date: 6/6/02, Space Station DPA failures, repairs made without customer notification and after customer inspection, build records incomplete or in error, tests skipped and out of sequence, inaccurate lot date codes used, many required electrical tests were not done, 20% PIND failure rate, hermeticity test failure rate 24%, X-ray failure rate 100%, room test electricals failure rate 8%. Contact: Karen Cunningham
JPL	Yes	28Vin, +/-15Vout, 5Vout, 30W	Unexpected Electrical Behavior – by Design		Date: 10/2/02, MER Oscillations encountered at start-up (on the bench) with a 100uF load. Could not start properly. See JPL report Z75796. Contact: Gary Bivins
Non-NASA			Qualtiy – element attach		Date: 2003 Capacitors came loose from the substrate during vibration testing. This defect was determined to have been screenable using X-Ray and pre-Cap inspection.
JPL	Yes	28Vin, +/-15Vout, Dual, 30W	Unexpected Electrical Behavior		Date: 8/27/03, Cloudsat Oscillations during EMC testing resulted in a catestrophic failure. See report Z81665. Contact: Gary Bivins
JPL	Yes	28Vin, +/-15Vout, Dual, 30W	Unexpected Electrical Behavior		Date: 10/9/03, Cloudsat Oscillations during EMC inrush current testing resulted in a catestrophic failure. See report Z82101. Contact: Garry Bivins
GSFC	Yes	TBD	TBD		Date: 12/31/03, Gravity Probe B Case not properly grounded. Electrically isolating and thermally conducting material installed between the mounting surface and the part case. Signal noise interfered with science data signal.
Non-NASA		`	Elements – commercial parts used and not tested properly		Date: 2004 Three different types of DC/DC converter hybrid microelectronics devices manufactured by a vendor are used in a program. In the course of the build of these hybrids, a number of issues/questions arose. The vendor used commercial Multilayer Ceramic Capacitors in the hybrids, and in two cases, at greater than the required 50% voltage derating. These commercial capacitors are not subjected to any stress screening tests such as burn-in to remove infant mortality, and testing at the hybrid level is not considered sufficient to achieve this purpose. The vendor also uses some of these capacitors to manufacture its own Stacked Ceramic Capacitors in varying number of stacked chips configuration, and many of these stacked capacitors do not receive stress screening tests. Finally, these capacitors utilize a pure tin finish on the terminations, raising concerns about the potential growth of tin whiskers during their service life. These issues raised concern of premature failure due to exceeding derating requirements and latent defects within unscreened capacitors. (af)
Non-NASA	Yes		Packaging Design – inductors mechanically attached to stacked capacitors		Date: 2004 During the QML testing for the three processes an unrelated test anomaly was identified when the solder joints of a J-leaded stacked capacitor lifted. Root cause analysis of the failure has determined that the input inductors were bonded directly to the J-leaded capacitors using red silicon adhesive and not to the substrate as shown in the drawing. The red silicon adhesive used to attach the inductors was excessive and constrained between the J- leaded capacitors adding torque and the amount of solder attaching the heal of the J-leaded stacked capacitor to the substrate was insufficient. (af)
GSFC	Yes	28Vin, 5Vout, Single, 65W	TBD		Date: 8/3/04, HST, STIS Side 2 Sudden loss of output voltage followed by input current increase in excess of 72 Amps in less than 40ms, causing STIS bus voltage to drop to or beyond point required to reset electronics prior to fault clearing.
JPL	Yes	28Vin, +/-15Vout, Double, 30W	Element – Wrong part installed		Date: 11/3/04, MRO The rise time of the inhibit pin was out of spec/too fast. Analysis showed that the wrong value capacitor was installed. See JPL report Z84953. Contact: Gary Bivins
Non-NASA			Element - Quality		Date: 2005 Cracks found in outer legs of E-core transformer core. The center leg was processed to install a gap. The cracks may have been installed during this process. (af)
GSFC	Yes	28Vin, 3.3Vout, Single, 60W	Packaging - Process	Gold-Tin IM	Date: 6/7/05, GLAST Excessive gold-tin intermetallic material found on metal joins. Contact: Chris Greenwell
GSFC	Yes	28Vin, 3.3Vout, Single, 60W	Packaging – Design, Element Selection	Narrow Gap	Date: 6/7/05, GLAST Internal terminal connection wire was less than 6 mils (and more than 5 mils) away from the top surface of a ceramic capacitor end termination. Contact: Chris Greenwell
NASA Contractor	Yes		Element Selection and Screening Technique	Possibly same issue as noted above	Date: 12/2/05 Converters built to SCD allowed use of film capacitors. This same design approach and screening practices (for the capacitors) were sited in an earlier application which had failed (see above).
NASA Contractor	TBD	28Vin, 15Vout	Incorrect Element Installed		Date: TBD (Late 2005 or early 2006) During element derating review, output tantalum capacitors were found to not meet derating requirements. Further investigation found that the parts were also not in accordance with the supplier’s BOM for this part type (22 uF, 25V installed vs 22 uF, 35V as designed). The parts were rejected.
Non-NASA			Unexpected Electrical Behavior – by Design		Date: 2006 When the main load is too low, the +5V output may repeatedly spike up and decay, or start up after several spikes/decay. This may also be related to capacitive loading on the Aux +V output. Prior to power-up, if an external back-feed voltage is present on the +5V output, the converter will not start-up as long as this external voltage is present. When large capacitance exists but with uneven current load distribution on the Aux. outputs, after initial turn on and turn off, the converter has a substantial “lock-out” time of approximately five seconds before it can be powered on again. With a low-load on the main 5V output and a moderate capacitance applied to the Aux. +V output, all outputs may repeatedly spike up and decay and never reach the intended voltages. (af)
NASA Contractor	Yes	28Vin, 3.3Vout, Single, 15W	Packaging – Quality	Element Placement	Date: 01/07, GLAST, IEM Assembly Hand placements of magnetic devices were highly variable causing some to be positioned so close to a nearby package pin that the magnetic wire insulation was damaged and the wire shorted to the pin.
GSFC	Yes	28Vin, 12Vout, Dual, 65W	Still being investigated		Date: 02/07, HST, ACS Side 2 Current seen on: i. converter return-to-bus, ii. Converter return to structure The S/C hull = floating, 10A – 20A for 3 seconds, with 5A – 8A spikes followed by 3 – 4 seconds of quiescent current, followed by 20A – 40A which blew the 20A rated fuse after 2 – 3 seconds. Gas pressure in the aft of the HST was 0.2 µTorr for hours oscillating by 10%. During the event this pressure first doubled then increased by 600X. Contact: Jack Shue
GSFC	Yes	28Vin, 12Vout, Dual, 40W	Unexpected Electrical Behavior – By Design		Date: 02/07, SDO, Ka-Band Transmitter Power Supply The converter would not consistently power up to +/- 12Vout when the unit was turned on from a cold start where the unit had been soaking at -20ºC. Sometimes the unit would only come up to +/-5Vout. The problem occurred for 4 out of 5 load conditions and didn’t occur only for the no load condition where no capacitor was connected to the outputs. The converter would consistently turn on from a cold start at all load conditions when the temperature was -15ºC. The hybrid would consistently not power up fully under any load condition except no load when the temperature was -25ºC. At no load (no capacitor) the unit would consistently power up at -25ºC. This behavior is believed to be related to the internal circuit design and internal part selections. It was not captured during manufacturer test because the test set-up, using electronic loads and power supplies, have a much slower rise time than what the converters saw in actual use (FET switched Vin and actual capacitors on the output). Contact: Carl Kellenbenz
GSFC	Yes	28Vin, 12Vout, Dual, 40W	Packaging – By Design	Case Material Selection	Date: 3/07, SDO, Gimbal Control Electronics In order to perform failure analysis on the part, it was de-installed from a flight board and reinstalled in a laboratory. When it was reinstalled a mounting flanged broke off. It was thought that the flange was cracked during its initial installation on the flight board. The package was made of Aluminum Silicon Carbide composite which is much more brittle than the usual material used (Steel or Kovar). Though an application note was written by the vendor about how to install this type of package, it was not referenced in the datasheet. The parts were of a 2005 production lot and the most recent update to the datasheet was in 2007. Contact: Carl Kellenbenz
GSFC	Yes	28Vin, 12Vout, Dual, 65W	Unexpected Electrical Behavior – By Design		Date: 3/07, HST Side 2 ACS During investigation of the ACS power supply failure (in-flight), flight-like boards were tested on the ground. At low loads when the 12 volt converters were disabled, the voltage before and after the EMI filter would drop, and in some cases the voltage drop was as much as 18 volts. The drop was at its worst when the input voltage was low (24 volts) . At 28 volts the drop was 10 volts, and at 32 volts there was no drop at all. The difference between the input side and the output side of the filter was less than a volt. At light loads when the converters are disabled the switching FET turns on and stays on. Contact: Jack Shue
JSC	No	120Vin, 24Vout, Single, 200W and 28Vin, 24Vout, Single, 200W	Electrical Overstress of Internal Element		Date: 5/07, Space Station/Shuttle, EVA Li Battery Charger Vout was found to become out-of-specification during bench operation/test. An error amplifier in the secondary stage, which is directly connected to a outer package pin, was found to be overstressed. The failure analysis has suggested it may have been caused by an ESD event. Investigation is ongoing. Contact: Jason Dugas
GSFC	Yes	28Vin, +/-15Vout, Dual, 40W	Unexpected Electrical Behavior due to Element Switch-out		Date: 5/07, GLORY A second source for a transistor unique to the synch circuit was used which changed the performance of the synch circuit. Vout regulation is lost when the synch pin is biased above 4V even though the rating for that pin is 4V to 10V. Contact: Cindy Tanner
GSFC	Yes	28Vin, +/-15Vout, Dual, 40W	Quality – Bond pull failures		Date: 2/08, GLORY Three bonds failed pull testing during DPA. Similar results were found in life test units. Contact: Thom Perry

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