What is the effect of the BUS-29854 isolation transformer on a 1553 terminal’s ESD immunity?
A. The transformer improves the ESD immunity of the overall 1553 terminal. By definition, a 1553 BC or RT terminal consists of both the analog/digital circuitry (e.g., the BU-61582X2) and the isolation transformers. A MIL-STD-1553 coupling transformer is required to exhibit a minimum common mode rejection ratio of 45 dB at 1 MHz. Since the isolation transformers that comprise part of the 1553 terminals are similarly constructed (in some cases, they’re the same transformer), they will generally have the same common mode rejection characteristics. Assuming that the ESD disturbance is applied between one of the 1553 stub (or bus) conductors and ground (which is generally the case), the transformers’ common mode rejection will, in effect, increase the ESD immunity of the overall terminal.Q. The Mini-ACE™ data sheet mentions transformers B-3226 (through-hole) and B-3227 (SMT) on sheet 4. We’ve been using the double-stacked TST-9007. Are all of these correct? Are there any new, smaller, shor
