sp336e Exar Corporation, sp336e Datasheet - Page 23

• Manufacturer Part Number: sp336e
• Description: 3.3v - 5v Programmable Rs-232/rs-485/rs-422 Serial Transceiver
• Manufacturer: Exar Corporation

SP336E
3.3V - 5V PROGRAMMABLE RS-232/RS-485/RS-422 SERIAL TRANSCEIVER
REV. 1.0.0
2.0 SUGGESTED APPLICATION DIAGRAMS
The SP336E supports all signals used in RS-232 over an 8 pin modular jack (RJ-45) as defined in TIA/EIA-
561. For DTE serial port only three drivers are required. Driver_1 is not used in this configuration and its driver
input should be tied to high or low.
SP336E may also be used to implement a standard serial port over a DB-9 connector (TIA/EIA-574 or the
standard IBM serial port). In that case either DSR or RI signal can be supported. Both DSR and RI are used
mainly for dial-up connections and are typically not needed on dedicated lines. If both signals are required, add
a discrete transceiver such as SP3220E.
An alternative implementation would be to use the SP336E to emulate the functionality of two dual-channel
RS-232 transceivers (2 x SP232’s or equivalent).
Loop-Back
Changing from RS-232 mode (MODE 001) to loop-back mode (MODE 000) duplicates the function of an
external loop-back plug. Loop-back can be used to test serial port functionality or to diagnose faults.
F
24. RS-232E S
P
(EIA-561 / EIA-574)
IGURE
ERIAL
ORT
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