ICL3221 INTERSIL [Intersil Corporation], ICL3221 Datasheet - Page 15

• Manufacturer Part Number: ICL3221
• Description: 1 Microamp Supply-Current, +3V to +5.5V, 250kbps, RS-232 Transmitters/Receivers
• Manufacturer: INTERSIL [Intersil Corporation]

High Data Rates
The ICL32XX maintain the RS-232 5V minimum transmitter
output voltages even at high data rates. Figure 10 details a
transmitter loopback test circuit, and Figure 11 illustrates the
loopback test result at 120kbps. For this test, all transmitters
were simultaneously driving RS-232 loads in parallel with
1000pF, at 120kbps. Figure 12 shows the loopback results
for a single transmitter driving 1000pF and an RS-232 load
at 250kbps. The static transmitters were also loaded with an
RS-232 receiver.
FIGURE 9. TRANSMITTER OUTPUT VOLTAGE vs LOAD
FIGURE 10. TRANSMITTER LOOPBACK TEST CIRCUIT
-1
-2
-3
-4
-5
-6
6
5
4
3
2
1
0
0
V
V
C
C
CC
CC
1
2
V
+
+
CC
1
CURRENT (PER TRANSMITTER, i.e., DOUBLE
CURRENT AXIS FOR TOTAL V
0.1 F
LOAD CURRENT PER TRANSMITTER (mA)
V
T1
T2
T3
CC
2
= 3.0V
C1+
C1-
C2+
C2-
T
R
EN
SHDN OR
FORCEOFF
IN
OUT
3
+
V
ICL3241/43
V
OUT
OUT
ICL32XX
3-15
4
+
V
-
CC
5
T
OUT
6
R
V+
5k
V-
IN
7
OUT+
V
V
OUT
OUT
8
CURRENT)
ICL3221 thru ICL3243
+
-
+
+
C
C
1000pF
9
3
4
10
Interconnection with 3V and 5V Logic
The ICL32XX directly interface with most 5V logic families,
including ACT and HCT CMOS. See Table 4 for more
information on possible combinations of interconnections.
POWER-SUPPLY
5V/DIV.
5V/DIV.
R1
R1
T1
T1
TABLE 4. LOGIC FAMILY COMPATIBILITY WITH VARIOUS
T1
T1
OUT
OUT
OUT
OUT
VOLTAGE
SYSTEM
IN
IN
(V)
3.3
5
5
V
C1 - C4 = 0.1 F
V
C1 - C4 = 0.1 F
FIGURE 11. LOOPBACK TEST AT 120kbps
FIGURE 12. LOOPBACK TEST AT 250kbps
CC
CC
SUPPLY VOLTAGES
= +3.3V
= +3.3V
VOLTAGE
SUPPLY
V
(V)
3.3
3.3
CC
5
2 s/DIV.
5 s/DIV.
Compatible with all CMOS
families.
Compatible with all TTL and
CMOS logic families.
Compatible with ACT and HCT
CMOS, and with TTL.
Incompatible with AC, HC, or
CD4000 CMOS.
COMPATIBILITY