DS3862

DS3862 Octal High Speed Trapezoidal Bus Transceiver February 1995 DS3862 Octal High Speed Trapezoidal Bus Transceiver General Description The DS3862 is an octal high speed schottky bus transceiver intended for use with terminated 120Ω impedance lines. It is specifically designed to reduce noise in unbalanced transmission systems. The open collector drivers generate precise trapezoidal waveforms with rise and fall times of 9 ns (typical), which are relatively independent of capacitive loading conditions on the outputs. This reduces noise coupling to the adjacent lines without any appreciable impact on the maximum data rate obtainable with high speed bus transceivers. In addition, the receivers use a low pass filter in conjunction with a high speed comparator, to further enhance the noise immunity. Tightly controlled threshold levels on the receiver provide equal rejection to both negative and positive going noise pulses on the bus. The external termination is intended to be a 180Ω resistor from the bus to 5V logic supply, together with a 390Ω resistor from the bus to ground. The bus can be terminated at one or both ends. Features n Guaranteed A.C. specifications on noise immunity and propagation delay over the specified temperature and supply voltage range n Temperature insensitive receiver thresholds track bus logic level and respond symmetrically to positive and negative going pulses n Trapezoidal bus waveforms reduce noise coupling to adjacent lines n Open collector driv...