SN75185

MULTIPLE RS-232 DRIVERS AND RECEIVERS

SLLS181A – DECEMBER 1994 – REVISED NOVEMBER 1998

6

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

Pulse

Generator

(see Note A)

CL

(see Note B)

RL

3 V

0 V

1.5 V

1.5 V

Input

t PHL

t PLH

90%

50%

10%

50%

10%

90%

t THL

t TLH

VOH

VOL

TEST CIRCUIT

VOLTAGE WAVEFORMS

Input

Output

VSS

VCC

VDD

NOTES: A.

The pulse generator has the following characteristics: tw = 25 µs, PRR = 20 kHz, ZO = 50 Ω, tr = tf < 50 ns.

B.

CL includes probe and jig capacitance.

Figure 3. Driver Test Circuit and Voltage Waveforms

VI

VDD

VCC

VSS

VT, VI

VDD

VCC

VSS

IOL

VOH

–IOH

VOL

Figure 4. Receiver Test Circuit

Figure 5. Receiver Test Circuit

Pulse

Generator

(see Note A)

CL

(see Note B)

RL

4 V

0 V

50%

50%

Input

t PHL

t PLH

90%

50%

10%

50%

10%

90%

t THL

t TLH

VOH

VOL

TEST CIRCUIT

VOLTAGE WAVEFORMS

Input

VSS

VDD

VCC

Output

NOTES: A.

The pulse generator has the following characteristics: tw = 25 µs, PRR = 20 kHz, ZO = 50 Ω, tr = tf < 50 ns.

B.

CL includes probe and jig capacitance.

Figure 6. Receiver Propagation and Transition Times