SP3223ECY-L-TR Datasheet, PDF (14/21 Pages) Exar Corporation – Intelligent +3.0V to +5.5V RS-232 Transceivers

RECEIVER ^+2.7V
RS-232 INPUT ^0V
VOLTAGES -2.7V
VCC
STATUS
0V
+5V
DRIVER
RS-232 OUTPUT _0V
VOLTAGES
-5V
S
H
U
T
D
O
W
N
tSTSL
tSTSH
tONLINE
Figure 21. AUTO ON-LINE^® Timing Waveforms
RS-232 Signal
at RECEIVER
INPUT
SHUTDOWN
ONLINE
YES
HIGH
LOW
NO
HIGH
HIGH
NO
HIGH
LOW
YES
NO
LOW
LOW
Table 5. AUTO ON-LINE^® Logic
HIGH/LOW
HIGH/LOW
STATUS
HIGH
LOW
LOW
HIGH
LOW
TRANSCEIVER
STATUS
Normal Operation
(AUTO ON-LINE©)
Normal Operation
Shutdown
(AUTO ON-LINE©)
Shutdown
Shutdown
Inactive Detection Block
RXINACT
RXIN
RS-232
Receiver Block
RXOUT
Figure 22. Stage I of AUTO ON-LINE^® Circuitry
Delay
Buffer
Delay
Buffer
R₁ON
R ₂ ON
SHUTDOWN
Figure 23. Stage II of AUTO ON-LINE^® Circuitry
Exar Corporation 48720 Kato Road, Fremont CA, 94538 • [phone] • www.exar.com
14
INACTIVE
SP3223E/EB/EU_101_062712