Switching Characteristics

V

Symbol

Parameter

Conditions

Min

Typ

Max

Units

t

pd0(D)

Differential Input to “0” Output

C

60

100

ns

t

pd1(D)

Differential Input to “1” Output

C

100

150

ns

t

pd0(S)

Strobe Input to “0” Output

C

30

70

ns

t

pd1(S)

Strobe Input to “1” Output

C

100

150

ns

Note 2: “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. Except for “Operating Temperature Range” they

are not meant to imply that the devices should be operated at these limits. The table of “Electrical Characteristics” provides conditions for actual device operation.

Note 3: Unless otherwise specified min/max limits apply across the −55˚C to +125˚C temperature range for the DS78C20 and across the 0˚C to +70˚C range for the

Note 4: All currents into device pins shown as positive, out of device pins as negative, all voltages referenced to ground unless otherwise noted. All values shown

as max or min on absolute value basis.

Note 5: Only one output at a time should be shorted.

Note 6: Refer to EIA-RS-422 for exact conditions.

Typical Applications

Note 7: (Optional internal termination resistor.)

a) Capacitor in series with internal line termination resistor, terminates the line and saves termination power. Exact value depends on line length.

b) Pin 1 connected to pin 2; terminates the line.

c) Pin 2 open; no internal line termination.

d) Transmission line may be terminated elsewhere or not at all.

Note 8: Optional to control response time.

RS-422/RS-423 Application

DS005798-2

RS-232-C Application with Hysteresis

DS005798-3

For signals which require fail-safe or have slow rise and fall times, use R1

and D1 as shown above. Otherwise, the positive input (pin 3 or 11) may be

connected to ground.

DS005798-4

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