Dual Differential Transceiver BTF1A
With Idle Bus Indicator
Data Sheet
March 2001
Timing Characteristics
Table 6. Driver Timing Characteristics (See Figure 3 and Figure 4.)
For tP1 and tP2 propagation delays over the temperature range, see Figure 13. Propagation delay test circuit con-
nected to output is shown in Figure 7. TA = −40 °C to +125 °C, VCC = 5 V ± 0.25 V.
Parameter
Propagation Delay:
Input High to Output1
Input Low to Output1
Capacitive Delay
Symbol
Min
Typ
Max
Unit
2
tP1
0.8
0.8
—
1.2
1.2
2.0
2.0
ns
ns
2
tP2
∆tp
0.02
0.03
ns/pF
Disable Time (either E1 or E2):
High-to-High Impedance
Low-to-High Impedance
Enable Time (either E1 or E2):
High Impedance to High
High Impedance to Low
Output Skew:
tPHZ
tPLZ
4
4
8
8
12
12
ns
ns
tPZH
tPZL
4
4
8
8
12
12
ns
ns
|tP1 – tP2|
tskew1
tskew2
∆tskew
ttLH
—
—
—
—
—
0.1
0.2
—
0.3
0.5
0.3
2
ns
ns
ns
ns
ns
|tPHH – tPHL|, |tPLH – tPLL|
Difference Between Drivers
Rise Time (20%—80%)
Fall Time (80%—20%)
0.7
0.7
ttHL
2
1. CL = 5 pF. Capacitor is connected from each output to ground.
2. tP1 and tP2 are measured from the 1.5 V point of the input to the crossover point of the outputs (see Figure 3).
Table 7. Receiver Timing Characteristics (See Figure 5 and Figure 6.)
For propagation delays (tPLH and tPHL) over the temperature range, see Figure 14 and Figure 15. Propagation delay
test circuit connected to output is shown in Figure 8. TA = −40 °C to +125 °C, VCC = 5 V ± 0.25 V.
Parameter
Symbol
Min
Typ
Max
Unit
Propagation Delay:
Input to Output High
tPLH
tPHL
1.5
1.5
2.5
2.5
4.0
4.0
ns
ns
Input to Output Low
Pulse Width Distortion, ltpHL-tpLHI:
Load Capacitance (CL) = 15 pF
Load Capacitance (CL) = 150 pF
Output Waveform Skews:
Part-to-Part Skew, TA = 75 °C
Part-to-Part Skew, TA = –40 °C to +125 °C
Same Part Skew
tskew1
tskew1
—
—
—
—
0.7
4.0
ns
ns
∆tskew1p-p
∆tskew1p-p
∆tskew
—
—
—
0.8
—
1.4
1.5
0.3
ns
ns
ns
—
Disable Time, CL = 5 pF:
High-to-high Impedance
Low-to-high Impedance
Enable Time:
tPHZ
tPLZ
—
—
5
5
12
12
ns
ns
High Impedance to High
High Impedance to Low
Rise Time (20%—80%)
Fall Time (80%—20%)
tPZH
tPZL
ttLH
ttHL
—
—
—
—
8
8
12
12
ns
ns
ns
ns
—
—
3.0
3.0
6
Agere Systems Inc.
AGERE [ AGERE SYSTEMS ]
