BTF1A Datasheet | Agere Systems

Features Driver Features s s s s s Electrostatic discharge (ESD) performance better than the 41 Series Lower power requirement than the 41 Series s Produces a logic zero in third state 400 m V difference voltage in third state Two line drivers per package Logic to convert TTL input logic levels to differential, pseudo-emmiter coupled logic (ECL) output logic levels No line loading when VCC = 0 V High output driver for 50 Ω loads 200 m A short-circuit current (typical) 2.0 ns maximum propagation delay <0.2 ns output skew (typical) Description The BTF1A device is a dual differential transceiver circuit that transmits and receives digital data over balanced transmission lines and is patible with Lucent Technologies Microelectronics Group differential drivers and receivers. It is designed to provide a strong logic zero when in the third state. The minimum difference voltage in the third state is 400 m V. It is designed specifically for bus applications where a well-defined logic state is needed when the bus is idle. The driver puts out a logic zero when in the third state mode, which is easily overriden by an active buffer on the bus. When all the buffers on the bus are inactive (third state), the signal on the bus is a zero indicating that the bus is idle. The dual drivers translate input TTL logic levels to differential pseudo-ECL output levels. The dual receiver converts differential input logic levels to TTL output levels. Each driver/receiver pair has its own mon enable control allowing serial data and a control clock to be transmitted and received on a single integrated circuit. The BTF1A transceiver requires the customer to supply termination resistors on the circuit board. The powerdown loading characteristics of the receiver input circuit are approximately 8 kΩ relative to the power supplies; hence, it will not load the transmission line when the circuit is powered down. For those circuits with termination resistors, the line will remain impedance matched...