Datasheet

MAX3380E/MAX3381E
+2.35V to +5.5V, 1µA, 2Tx/2Rx RS-232 Transceivers
with ±15kV ESD-Protected I/O and Logic Pins
8 _______________________________________________________________________________________
+0.3V
-0.3V
INVALID
R_IN
INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR
AT LEAST 30μs.
30µs
TIMER
R
+2.7V
-2.7V
INVALID
R_IN
INVALID DEASSERTED IF ANY RECEIVER INPUT HAS BEEN BETWEEN +2.7V AND -2.7V
FOR LESS THAN 30μs.
0.3μs
TIMER
R
Figure 2a. I NVALID Functional Diagram, I NVALID Low
Figure 2b. I NVALID Functional Diagram, I NVALID High
Table 1. AutoShutdown Plus Truth Table
OPERATION
STATUS
FORCEON
FORCEOFF
VALID
RECEIVER
LEVEL
RECEIVER OR
TRANSMITTER EDGE
WITHIN 30s
T_OUT R_OUT
Shutdown
(Forced Off)
X 0 X X High-Z Active
Normal Operation
(Forced On)
1 1 X X Active Active
Normal Operation
(AutoShutdown
Plus)
0 1 X Yes Active Active
Shutdown
(AutoShutdown
Plus)
0 1 X No High-Z Active
Normal Operation
INVALID 1 Yes X Active Active
Normal Operation
INVALID 1 X Yes Active Active
Shutdown INVALID 1 No No High-Z Active
Normal Operation
(AutoShutdown)
INVALID INVALID Yes X Active Active
Shutdown
(AutoShutdown)
INVALID INVALID No X High-Z Active
X = Don’t care