HI-1585

The HI-1585 is an ultra-low power CMOS dual transceiver designed to meet the requirements of  the MIL-STD-1553 and MIL-STD-1760 specifications.

The HI-1585 is the first MIL-STD-1553/1760 transceiver to provide transmitter-induced tail-off compensation. Two methods are provided, namely, input data synchronization and programmable tail-off adjustment. The former enables a clocked input for the logic-level transmit signal pair to provide precise synchronization and mitigate input signal timing differences. The latter option provides a means for digitally tuning tail-off characteristics for problem designs that fail to meet 'output symmetry' (tail-off) requirements, usually a result of non-optimal board design and layout. Compensation is pin-selected and bus-specific. Three adjustment levels are provided for either polarity, reducing tail-off amplitude up to ±75 mV DC. These unique features allow the user to compensate for impedance asymmetries in either the input or load circuits, effectively minimizing any systematic offset introduced by the application environment.

The HI-1585 also provides optional Receive output pulse extension. With traditional MIL-STD-1553 transceivers, low amplitude receive signals can result in RX/nRX pulses less than 100ns wide. When this feature is enabled, RX/nRX output pulse widths do not drop below 300ns, greatly simplifying decoder design and enhancing noise performance.

The transmitter section of each bus takes complementary CMOS / TTL Manchester II bi-phase data and converts it to differential voltages suitable for driving the bus isolation transformer. Separate transmitter inhibit control signals are provided for each transmitter. The receiver section of the each bus converts the 1553 bus bi-phase analog signals to complementary CMOS / TTL data suitable for input to a Manchester decoder. Each receiver has a separate enable input, which forces the receiver outputs to the bus idle state (logic '0') when disabled.

The device is packaged in the industries smallest MIL-STD-1553 transceiver package, a 48-pin plastic 6mm x 6mm QFN with an exposed heat sink pad, which may be soldered to the PCB ground plane for optimal thermal dissipation. The device is available in industrial −40^oC to +85^oC and extended −55^oC to +125^oC temperatures, with optional burn-in available on the extended temperature range.