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 t
P1
and t
P2
propagation delays over the temperature range, see Figure 13. Propagation delay test circuit con-
nected to output is shown in Figure 7. T
A
=
−40
°C to +125 °C, V
CC
= 5 V
±
0.25 V.
Parameter
Propagation Delay:
Input High to Output
1
Input Low to Output
1
Capacitive Delay
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:
|t
P1
– t
P2
|
|t
PHH –
t
PHL
|, |t
PLH
– t
PLL
|
Difference Between Drivers
Rise Time (20%—80%)
Fall Time (80%—20%)
Symbol
t
P1
2
t
P2
2
∆tp
t
PHZ
t
PLZ
t
PZH
t
PZL
t
skew1
t
skew2
∆t
skew
t
tLH
t
tHL
Min
0.8
0.8
—
4
4
4
4
—
—
—
—
—
Typ
1.2
1.2
0.02
8
8
8
8
0.1
0.2
—
0.7
0.7
Max
2.0
2.0
0.03
12
12
12
12
0.3
0.5
0.3
2
2
Unit
ns
ns
ns/pF
ns
ns
ns
ns
ns
ns
ns
ns
ns
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 (t
PLH
and t
PHL
) over the temperature range, see Figure 14 and Figure 15. Propagation delay
test circuit connected to output is shown in Figure 8. T
A
=
−40
°C to +125 °C, V
CC
= 5 V
±
0.25 V.
Parameter
Propagation Delay:
Input to Output High
Input to Output Low
Pulse Width Distortion, ltpHL-tpLHI:
Load Capacitance (C
L
) = 15 pF
Load Capacitance (C
L
) = 150 pF
Output Waveform Skews:
Part-to-Part Skew, T
A
= 75 °C
Part-to-Part Skew, T
A
= –40 °C to +125 °C
Same Part Skew
Disable Time, C
L
= 5 pF:
High-to-high Impedance
Low-to-high Impedance
Enable Time:
High Impedance to High
High Impedance to Low
Rise Time (20%—80%)
Fall Time (80%—20%)
6
Symbol
t
PLH
t
PHL
tskew1
tskew1
∆tskew1p-p
∆tskew1p-p
∆tskew
t
PHZ
t
PLZ
t
PZH
t
PZL
t
tLH
t
tHL
Min
1.5
1.5
—
—
—
—
—
—
—
—
—
—
—
Typ
2.5
2.5
—
—
0.8
—
—
5
5
8
8
—
—
Max
4.0
4.0
0.7
4.0
1.4
1.5
0.3
12
12
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
12
ns
12
ns
3.0
ns
3.0
ns
Agere Systems Inc.
AGERE [ AGERE SYSTEMS ]
