SP3223U Datasheet, PDF (11/24 Pages) Sipex Corporation – High Speed Intelligent +3.0V to +5.5V RS-232 Transceivers

DEVICE: SP3223U
SHUTDOWN
EN
0
0
T_XOUT
High Z
R_XOUT
Active
0
1
High Z High Z
1
0
Active
Active
1
1
Active
High Z
DEVICE: SP3243U
SHUTDOWN
0
T OUT
X
High Z
R OUT
X
High Z
R OUT
2
Active
1
Active
Active
Active
Table 2. SHUTDOWN and EN Truth Tables
Note: In AUTO ON-LINE^® Mode where ONLINE =
GND and SHUTDOWN = V_CC, the device will shut down
if there is no activity present at the Receiver inputs.
+3V to +5V
+
C5 0.1µF
+
C1 0.1µF
+
C2 0.1µF
TTL/CMOS
INPUTS
VCC
C1+
V+
C1-
C2+ SP3223U
SP3243U
V-
C2-
T₁IN
T₁OUT
T_XIN
T_XOUT
+
C3 0.1µF
C4 0.1µF
+
TTL/CMOS
OUTPUTS
VCC
To µP Supervisor
Circuit
R₁OUT
R₁IN
5kΩ
R_XOUT
EN *
R_XIN
5kΩ
1000pF
SHUTDOWN
ONLINE
STATUS
GND
1000pF
* SP3223EU Only
Figure 17. Loopback Test Circuit for RS-232 Driver
Data Transmission Rates
Figure 17 shows a loopback test circuit used to
test the RS-232 Drivers. Figure 18 shows the test
results where one driver was active at 1Mbps and
all three drivers loaded with an RS-232 receiver
in parallel with a 250pF capacitor. Figure 19
shows the test results of the loopback circuit with
all drivers active at 250kbps with typical
RS-232 loads in parallel with 1000pF capacitors. A
superior RS-232 data transmission rate of 1Mbps
makes the SP3223U/3243U series an ideal match
for high speed LAN and personal computer
peripheral applications.
Receivers
The receivers convert +5.0V EIA/TIA-232
levels to TTL or CMOS logic output levels. The
SP3223U receivers have an inverting output that
can be disabled by using the EN pin.
Figure 18. Loopback Test results at 1Mbps
Figure 19. Loopback Test results at 250Kbps
Date: 5/25/04
SP3223U/3243U +3.0V to +5.5V RS-232 Transceivers
11
© Copyright 2004 Sipex Corporation