ISL4241E Datasheet, PDF (11/14 Pages) Intersil Corporation – QFN Packaged, ±15kV ESD Protected, +2.7V to +5.5V, 10Nanoamp, 250kbps, +2.7V to +5.5V, 10Nanoamp, 250kbps,

5V/DIV.
FORCEOFF
ISL4241E, ISL4243E
5V/DIV
T1
T1_IN
2V/DIV.
T1_OUT
T2
V_CC = +3.3V
C1 to C4 = 0.1µF
TIME (20µs/DIV)
FIGURE 8. TRANSMITTER OUTPUTS WHEN EXITING
POWER-DOWN
Operation Down to 2.7V
The ISL4241E, ISL4243E transmitter outputs meet RS-562
levels (±3.7V), at the full data rate, with V_CC as low as 2.7V.
RS-562 levels typically ensure inter operability with RS-232
devices.
High Data Rates
The ISL4241E, ISL4243E maintain the RS-232 ±5V
minimum 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.
V_CC
0.1µF ⁺
+
C₁
+
C₂
C1+
V_CC
V+
C1-
ISL4241E
C2+ ISL4243E ^V-
C2-
T_IN
T_OUT
R_OUT
R_IN
+
C₃
+C⁴
1000pF
V_CC
FORCEON
5k
FORCEOFF or SHDN
FIGURE 9. TRANSMITTER LOOPBACK TEST CIRCUIT
R1_OUT
V_CC = +3.3V
C1 to C4 = 0.1 µF
5µs/DIV
FIGURE 10. LOOPBACK TEST AT 120kbps
5V/DIV.
T1_IN
T1_OUT
R1_OUT
V_CC = +3.3V
C1 - C4 = 0.µF
2µs/DIV
FIGURE 11. LOOPBACK TEST AT 250kbps
Interconnection with 3V and 5V Logic
The ISL4241E, ISL4243E directly interface with 5V CMOS
and TTL logic families. Nevertheless, with the ISL4241E,
ISL4243E at 3.3V, and the logic supply at 5V, AC, HC, and
CD4000 outputs can drive ISL4241E, ISL4243E inputs, but
ISL4241E, ISL4243E outputs do not reach the minimum V_IH
for these logic families. See Table 3 for more information.
TABLE 3. LOGIC FAMILY COMPATIBILITY WITH VARIOUS
SUPPLY VOLTAGES
SYSTEM
V_CC
POWER-SUPPLY SUPPLY
VOLTAGE VOLTAGE
(V)
(V)
COMPATIBILITY
3.3
3.3 Compatible with all CMOS
families.
5
5
Compatible with all TTL and
CMOS logic families.
11
FN8037.7
June 10, 2010