MIL-STD-1553 TRANSFORMERS

Transcription

1 AN/T-1 A Subsidiary of Data Device Corporation 40 Orville Drive, Bohemia, NY Phone: (631) ; Fax: (631) Web site: MIL-STD-1553 TRANSFORMERS By Beta Transformer Technology Corporation INTRODUCTION Beta Transformer Technology Corporation (BTTC), a subsidiary of ILC Data Device Corporation (DDC), is a leader in isolation and coupling transformers for MIL-STD-1553 data bus. Beta is located within DDC s two-building complex in Bohemia, NY. The close relationship between Beta and DDC enables the companies engineers to work hand-in-hand in developing new products. Using advanced technology and manufacturing processes, Beta has become the recognized source for custom interface transformers that continually meet or exceed the requirements for military systems. Beta transformers provide the turns ratio configurations, component isolation, common mode rejection, and other electrical and mechanical characteristics necessary for MIL-STD A & B compliance. Individual data sheets on all transformers are available through the Beta website. The step-up and step-down turns ratio that are available with our transformers compliment DDC s entire 1553 product line and are compatible with competitors drivers, receivers and transceivers. Beta transformers are low-profile (down to height), modular units that are multi-tapped to accommodate existing system configurations. Encapsulated and hermetically sealed interface transformers accommodate printed circuit board mounting. Special lead bending for surface mounted units, along with custom part marking, is also available. The waveform fidelity of Beta transformers make them an excellent choice for MIL- STD-1553 sinusoidal or trapezoidal applications. DESC QUALIFIED Beta is recognized as a qualified source of interface transformers specified by the Defense Electronics Supply Center (DESC) MIL-PRF-21038/27-01 through These transformers are designed and manufactured in accordance with MIL-PRF For space applications, transformers are manufactured and tested in accordance with MIL-STD-981 which details requirements for space-level transformers. Many programs, however, have unique requirements. Beta, like DDC, maintains the flexibility to satisfy these requirements on a program-by-program basis. Lead times for products are: MIL-Level: 1-3 Months Space-Level: 4-8 Months Pricing: Contact Factory Directly SSQ DRAWING Beta passed an IBM Quality Survey for MIL-STD-981 S level manufacturing Data Device Corporation All trademarks are the property of their respective owners

2 MEAN TIME BETWEEN FAILURE (HOURS) TEMPERATURE CASE ( C ) SPACE FLIGHT FIGURE 1. RELIABILITY PREDICTION FOR 1553 INTERFACE TRANSFORMERS 2

3 Subsequently, Beta has delivered to IBM, along with other major suppliers for International Space Station Program, both epoxy-cased and hermetically sealed pulse transformers. Beta, along with Northrop-Grumman Space Station Integration in Reston VA, developed the SSQ specification. This specification, entitled Transformer MIL-STD-1553 Terminal Interface, Space Quality, standardizes the transformers used on International Space Station Program. The products and part numbers listed in this specification are Beta s standard products. At this writing, Beta is listed as the only approved supplier to SSQ Beta s Statistical Process Control (SPC) program has been recognized and approved by UL and it is compliant with ISO-9001;2000. ESD RATINGS Electro Static Discharge (ESD) testing was performed on Beta s MIL-PRF /27 QPL Interface transformers according to MIL-STD-883 method The transformers were determined to have an ESD failure threshold classification of class 3 (in accordance EPOXY-CASED UNITS 1) Diallyl Phtalate Case 2) Hot Solder Dipped Copper Clad Steel Leads 3) 155 C Rated, Solderable Magnet Wire 4) Ferrite Core 5) Epoxy Encapulation 6) Core Isolation Coating 7) SN10 8) Mylar Tape with table III.) and a threshold of greater than 5 kv per the human body model. The IMCS 5000 automated ESD test system was used to perform this test. An integral part of Beta s manufacturing process is it s test department where both electrical parameters and enviornmental testing is performed. Custom-designed test fixtures and automated test stands facilitate fast, repetitive, accurate testing of all 1553 interface transformers. Beta s test department is also equipped to perform burn-in, life test, and thermal shock testing. All other enviormental tests are performed at a local testing laboratory. Using the calculations from par of MIL-HDBK-217, the following mean time between failure, (MTBF) table, has been TABLE 1. PRODUCT MATERIAL BREAKDOWN HERMETICALLY SEALED UNITS 1) Nickel/Kovar Case, Gold Over Nickel Plated Kovar Case Available on Request 2) Gold Plated Nickel Kovar Leads 3) 155 C Rated, Solderable Magnet Wire 4) Ferrite Core 5) Silicone Encapsulate Potting 6) Core Isolation Coating 7) SN10 8) Mylar Tape generated to cover all of Beta s 1553 interface transformers (see FIGURE 1). MATERIALS The materials used on all of Beta s 1553 interface transformers can be broken into two main categories: (1) epoxy-cased units and (2) hermetically sealed units. TABLE 1. lists a breakdown of materials on these two product groups. Rp L1 Rs Rp = 0.56Ω Rc = 5500Ω Rs = 0.4Ω Cc = 62pF Lm = 10mH L1 = 0.7µH Cc Rc Lm FIGURE 2. TYPICAL EQUIVALENT CIRCUIT CONFIGURATION 3

4 EQUIVALENT CIRCUIT The nominal equivalent circuit shown in FIGURE 2 is for transformer BUS-25679, referred to terminals (1-2) or (2-3) for a 1 MHz sine wave input. Parameters Rc and Lm, being functions of the ferrite core material, will vary over voltage level, frequency and temperature. Rp & Rs are copper wire resistances and will change over temperature as per the coefficient of standard annealed copper. L1 and Cc are generally functions of unit geometry and remain mainly unchanges over changing conditions compared to other parameters. This equivalent circuit is useful for computer modeling in conjunction with other circuit elements. INPUT IMPEDANCE VERSUS FREQUENCY The Impedance vs. Frequency plot shown in FIGURE 3 is also for transformer 25679, referred at terminals (1-3) and (5-7), from 75 khz to 1MHz, at 1V and a temperature of 25 C.,MIL-STD- 1553B requires a minimum value of 3kΩ at terminals (1-3) for this impedance over the frequency range of 75 khz to 1 MHz when measured with a 1 Vrms sine wave. CONCLUSION Beta transformer products provide the quality, reliability and precision needed to satisfy industry requirements. Beta s production capabilities ensure timely delivery of customer orders. This, coupled with broad design capabilities, makes Beta the ideal source for 1553 interface magnetics for military, space, and industrial applications. 75K 60K IMPEDANCE (Ω) 45K 30K TERMINALS (1-3) 15K TERMINALS (5-7) 7.5K 100K 200K 300K 400K 500K 600K 700K 800K 900K 1M FREQUENCY ( Hz) FIGURE 3. RELIABILITY PREDICTION FOR 1553 INTERFACE TRANSFORMERS 4

5 The information in this data sheet is believed to be accurate; however, no responsibility is assumed by Beta Transformer Technology Corporation for its use, and no license or rights are granted by implication or otherwise in connection therewith. Specifications are subject to change without notice. Visit our Web site at for the latest information. A Subsidiary of Data Device Corporation 40 Orville Drive, Bohemia, NY Phone: (631) ; Fax: (631) Web site: AN/T-1 05/04-0 PRINTED IN THE U.S.A. 5