DS3890 datasheet(4/8 Pages) NSC

4 / 8 page

General Descriptions (Continued)

The DS3892 receiver inputs incorporate a low pass filter in

conjunction with high speed comparator to further enhance

the noise immunity Both devices provide equal rejection to

both positive and negative noise pulses (typically 6 ns) on

the bus

The DS3890 features TTL compatible inputs while the

DS3892 inputs are BTL compatible The control inputs on all

devices are TTL compatible

BTL ‘‘Backplane Transceiver Logic’’ is a new logic signaling

method developed by IEEE P896 Future Bus Stan-

dards Committee This standard was adopted to enhance

the performance of Backplane Busses BTL compatible bus

interface circuits feature low capacitance drivers to mini-

mize bus loading a 1V nominal signal swing for reduced

power consumption and receivers with precision thresholds

for maximum noise immunity This new standard overcomes

some of the fundamental limitations of TTL bus transceivers

in heavily loaded backplane bus applications Devices de-

signed to this standard provide significant improvements in

switching speed and data integrity

AC Switching Waveforms

TLF8700 – 4

Note

tRetFk10 ns from 10% to 90%

TLF8700 – 5

FIGURE 1

Driver Propagation Delays

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DS3890 Datasheet(PDF) 4 Page - National Semiconductor (TI)