Aeroflex Colorado Springs ERRATA ERR-SPW-002-01 LVDS output levels for the UT200SpW4RTR SpaceWire Router Product Name: Table 1: Cross Reference of Applicable Products Manufacturer Part SMD # Number 4-PORT SPACEWIRE ROUTER Device Type Internal PIC* UT200SpW4RTR NA NA WD41A Note 1 Note 1: WD41A will not be sold against the SMD. All SMD shipments will be with Rev B Silicon. *PIC = Product Identification Code 1.0 Overview The UT200SpW4RTR 4-Port SpaceWire router contains an anomaly that prevents the device from complying with the Low Voltage Differential Signaling, LVDS, levels called out in ECSS-E-ST-50-12C Section 6.1. The SpaceWire Standard calls for a LVDS physical layer as defined in ANSI/TIA/EIA-644, Electrical Characteristics of Low Voltage Differential Signaling Interface Circuits. Revision A of the Aeroflex router does not comply with the levels called out for Differential Output Voltage (VOD or VT) and Offset Voltage (VOS) sections 4.1.1 and 4.1.2 in ANSI/TIA/EIA-644. Additionally the UT200SpW4RTR does not show in family characteristics for High-Level Output Voltage (VOH) when compared to other Aeroflex LVDS and SpaceWire products. Table 2 below shows the Differential Output Voltage, Offset Voltage, and High-Level Output Voltage comparison between Revision A and the targeted Revision B limits for the UT200SpW4RTR. SYMBOL Parameter VOD VOS VOH Differential Output Voltage Offset Voltage High-Level Output Voltage Rev A MIN MAX 362 434 1.38 1.53 -1.75 Rev B MIN MAX 250 400 1.125 1.450 -1.625 Units mV V V Table 2. Anomaly comparison table between Rev A and Rev B of the UT200SpW4RTR 2.0 Corrective Action This anomaly can not be prevented. 3.0 Rev A vs. Rev B Revision A of the UT200SpW4RTR contains this anomaly. Revision B will correct this errata. Release Date: 12/14/09 Page 1 of 1 Modification Date: