Datasheet

ADM3485E
Rev. D | Page 4 of 16
TIMING SPECIFICATIONS
V
CC
= 3.3 V, T
A
= 25°C.
Table 2.
Parameter Symbol Min Typ Max Unit Test Conditions/Comments
DRIVER
Maximum Data Rate 12 15
Differential Output Delay t
DD
1 22 35 ns R
L
= 60 Ω, C
L1
= C
L2
= 15 pF (see Figure 6)
Differential Output Transition Time t
TD
3 11 25 ns R
L
= 60 Ω, C
L1
= C
L2
= 15 pF (see Figure 6)
Propagation Delay
From Low to High Level t
PLH
7 23 35 ns R
L
= 27 Ω (see Figure 7)
From High to Low Level t
PHL
7 23 35 ns R
L
= 27 Ω (see Figure 7)
|t
PLH
− t
PHL
| Propagation Delay Skew t
PDS
–1.4 ±8 ns R
L
= 27 Ω (see Figure 7)
Enable/Disable Timing
Enable Time to Low Level t
PZL
42 90 ns R
L
= 110 Ω (see Figure 9)
Enable Time to High Level t
PZH
42 90 ns R
L
= 110 Ω (see Figure 8)
Disable Time from Low Level t
PLZ
35 80 ns R
L
= 110 Ω (see Figure 9)
Disable Time from High Level t
PHZ
35 80 ns R
L
= 110 Ω (see Figure 8)
Enable Time from Shutdown to Low Level t
PSL
650 900 ns R
L
= 110 Ω (see Figure 9)
Enable Time from Shutdown to High Level t
PSH
650 900 ns R
L
= 110 Ω (see Figure 8)
RECEIVER
Propagation Delay
From Low to High Level t
RPLH
25 62 90 ns V
ID
= 0 V to 3.0 V, C
L
= 15 pF (see Figure 10)
From High to Low Level t
RPHL
25 62 90 ns V
ID
= 0 V to 3.0 V, C
L
= 15 pF (see Figure 10)
|t
RPLH
− t
RPHL
| Propagation Delay Skew t
RPDS
6 ±10 ns V
ID
= 0 V to 3.0 V, C
L
= 15 pF (see Figure 10)
Enable/Disable Timing
Enable Time to Low Level t
RPZL
25 50 ns C
L
= 15 pF (see Figure 11)
Enable Time to High Level t
RPZH
25 50 ns C
L
= 15 pF (see Figure 11)
Disable Time from Low Level t
RPLZ
25 45 ns C
L
= 15 pF (see Figure 11)
Disable Time from High Level t
RPHZ
25 45 ns C
L
= 15 pF (see Figure 11)
Enable Time from Shutdown to Low Level t
RPSL
720 1400 ns C
L
= 15 pF (see Figure 11)
Enable Time from Shutdown to High Level t
RPSH
720 1400 ns C
L
= 15 pF (see Figure 11)
Time to Shutdown
1
t
SHDN
80 190 300 ns
1
The transceivers are put into shutdown mode by bringing the
RE
high and the DE low. If the inputs are in this state for less than 80 ns, the parts are guaranteed not to
enter shutdown. If the parts are in this state for 300 ns or more, the parts are guaranteed to enter shutdown.