ISL4223E INTERSIL [Intersil Corporation], ISL4223E Datasheet - Page 9

• Manufacturer Part Number: ISL4223E
• Description: QFN Packaged, +/-15kV ESD Protected, +2.7V to +5.5V, 150Nanoamp, 250kBps, RS-232 Transmitters/Receivers
• Manufacturer: INTERSIL [Intersil Corporation]

Note that the transmitters enable only when the magnitude
of the supplies exceed approximately 3V.
Operation Down to 2.7V
ISL422XE transmitter outputs meet RS-562 levels (
the full data rate, with V
typically ensure inter operability with RS-232 devices.
High Data Rates
The ISL422XE maintain the RS-232
transmitter output voltages even at high data rates. Figure 9
details a transmitter loopback test circuit, and Figure 10
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 11 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.
5V/DIV.
2V/DIV.
FIGURE 8. TRANSMITTER OUTPUTS WHEN EXITING
FIGURE 9. TRANSMITTER LOOPBACK TEST CIRCUIT
V
V
C
C
CC
CC
1
2
V
C1 - C4 = 0.1µF
+
+
CC
= +3.3V
POWERDOWN
FORCEOFF
0.1µF
C1+
C1-
C2+
C2-
T
R
FORCEON
FORCEOFF
IN
OUT
+
CC
TIME (20µs/DIV.)
ISL422XE
as low as 2.7V. RS-562 levels
V
CC
9
T
OUT
5k
±
R
5V minimum
V+
V-
IN
±
ISL4221E, ISL4223E
T1
T2
+
+
3.7V), at
C
C
1000pF
3
4
Interconnection with 3V and 5V Logic
The ISL422XE directly interface with 5V CMOS and TTL
logic families. Nevertheless, with the ISL422XE at 3.3V, and
the logic supply at 5V, AC, HC, and CD4000 outputs can
drive ISL422XE inputs, but ISL422XE outputs do not reach
the minimum V
more information.
POWER-SUPPLY
5V/DIV.
5V/DIV.
R1
R1
T1
T1
TABLE 3. LOGIC FAMILY COMPATIBILITY WITH VARIOUS
T1
T1
OUT
OUT
OUT
OUT
VOLTAGE
SYSTEM
IN
IN
3.3
(V)
5
5
V
C1 - C4 = 0.1µF
V
C1 - C4 = 0.1µF
FIGURE 10. LOOPBACK TEST AT 120kBps
FIGURE 11. LOOPBACK TEST AT 250kBps
CC
CC
SUPPLY VOLTAGES
= +3.3V
= +3.3V
IH
for these logic families. See Table 3 for
VOLTAGE
SUPPLY
V
(V)
3.3
3.3
CC
5
2µs/DIV.
Compatible with all CMOS
families.
Compatible with all TTL and
CMOS logic families.
Compatible with ACT and HCT
CMOS, and with TTL. ISL422XE
outputs are incompatible with AC,
HC, and CD4000 CMOS inputs.
5µs/DIV.
COMPATIBILITY