13

FN4876.10

March 1, 2006

1000pF, at 120kbps. Figure 14 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.

Interconnection with 3V and 5V Logic

The ICL32XX directly interface with 5V CMOS and TTL logic

families. Nevertheless, with the ICL32XX at 3.3V, and the

logic supply at 5V, AC, HC, and CD4000 outputs can drive

ICL32XX inputs, but ICL32XX outputs do not reach the

information.

FIGURE 12. TRANSMITTER LOOPBACK TEST CIRCUIT

FIGURE 13. LOOPBACK TEST AT 120kbps

ICL32XX

FORCEOFF

+

+

+

+

1000pF

V+

V-

5K

C1+

C1-

C2+

C2-

+

0.1

µF

FORCEON

5

µs/DIV.

5V/DIV.

C1 - C4 = 0.1

µF

FIGURE 14. LOOPBACK TEST AT 250kbps

TABLE 4. LOGIC FAMILY COMPATIBILITY WITH VARIOUS

SUPPLY VOLTAGES

SYSTEM

POWER-SUPPLY

VOLTAGE (V)

SUPPLY

VOLTAGE

(V)

COMPATIBILITY

3.3

3.3

Compatible with all CMOS families.

5

5

Compatible with all TTL and

CMOS logic families.

5

3.3

Compatible with ACT and HCT

CMOS, and with TTL. ICL32XX

outputs are incompatible with AC,

HC, and CD4000 CMOS inputs.

2

µs/DIV.

5V/DIV.

C1 - C4 = 0.1

µF

ICL3224, ICL3226, ICL3238, ICL3244