Datasheet

MAX3140
SPI/MICROWIRE-Compatible UART with Integrated
True Fail-Safe RS-485/RS-422 Transceivers
_______________________________________________________________________________________ 7
SWITCHING CHARACTERISTICS—SRL = GND
(V
CC
= +5V ±5%, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V
CC
= +5V and T
A
= +25°C.)
PARAMETER SYMBOL MIN TYP MAX UNITS
Driver Disable Time from Low t
DLZ
100 ns
Driver Enable to Output Low t
DZL
150 ns
Driver Enable to Output High t
DZH
150 ns
Maximum Data Rate f
MAX
10 Mbps
Driver Disable Time from High t
DHZ
100 ns
Receiver Input to Output
t
RPLH
,
t
RPHL
106 150 ns
|
t
RPLH
- t
RPHL
|
Differential
Receiver Skew
t
RSKD
0±10ns
Receiver Enable to Output Low t
RZL
20 50 ns
Driver Output Skew
|
t
DPLH
- t
DPHL
|
Driver Input to Output
t
DPLH
34 60
ns
t
DSKEW
-2.5 ±10 ns
Driver Rise or Fall Time t
DR,
t
DF
14 25 ns
Receiver Enable to Output High t
RZH
20 50 ns
Receiver Disable Time from Low t
RLZ
20 50 ns
Receiver Disable Time from
High
t
RHZ
20 50 ns
Time to Shutdown t
SHDN
50 200 600 ns
Driver Enable from Shutdown to
Output High
t
DZH(SHDN)
250 ns
Driver Enable from Shutdown to
Output Low
t
DZL(SHDN)
250 ns
Receiver Enable from Shutdown
to Output High
t
RZH(SHDN)
3500 ns
34 60
CONDITIONS
Figures 2 and 8, C
L
= 100pF, S2 closed
Figures 4 and 6, C
L
= 15pF, S1 closed
Figures 2 and 8, C
L
= 100pF, S1 closed
Figures 4 and 6, C
L
= 100pF, S1 closed
Figures 4 and 6, C
L
= 100pF, S2 closed
Figures 4 and 6, C
L
= 15pF, S2 closed
Figures 7 and 9,
|
V
ID
|
≥ 2.0V,
rise and fall time of V
ID
≤ 15ns
Figures 2 and 8, C
L
= 100pF, S2 closed
(Note 5)
Figures 7 and 9,
|
V
ID
|
≥ 2.0V,
rise and fall time of V
ID
≤ 15ns
Figures 2 and 8, C
L
= 100pF, S1 closed
Figures 4 and 6, C
L
= 15pF, S2 closed
Figures 4 and 6, C
L
= 15pF, S1 closed
Figures 2 and 8, C
L
= 100pF, S2 closed
Figures 3 and 5, R
DIFF
= 54Ω,
C
L1
= C
L2
= 100pF
Receiver Enable from Shutdown
to Output Low
Figures 3 and 5, R
DIFF
= 54Ω,
C
L1
= C
L2
= 100pF
t
RZL(SHDN)
3500
Figures 3 and 5, R
DIFF
= 54Ω,
C
L1
= C
L2
= 100pF
nsFigures 2 and 8, C
L
= 100pF, S1 closed
t
DPHL
Note 1: All currents into the device are positive; all currents out of the device are negative. All voltages are referred to device
ground unless otherwise noted.
Note 2: ΔV
OD
and ΔV
OC
are the changes in V
OD
and V
OC
, respectively, when the Dl input changes state.
Note 3: The SRL pin is internally biased to V
CC
/2 by a 100kΩ/100kΩ resistor-divider. It is guaranteed to be V
CC
/2 if left unconnected.
Note 4: Maximum current level applies to peak current just prior to foldback-current limiting; minimum current level applies during
current limiting.
Note 5: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns, the
device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 600ns, the device is guaranteed
to have entered shutdown.