High Data Rates

The MAX3311/MAX3313 maintain RS-232-compatible

transmitter output voltage (±3.7V minimum) even at

high data rates. Figure 2 shows a transmitter loopback

test circuit. Figure 3 shows the loopback test result at

120kbps, and Figure 4 shows the same test at

250kbps.

460kbps, 1µA Supply Current,

RS-232-Compatible Transceivers in µMAX

6

_______________________________________________________________________

Figure 2. Loopback Test Circuit

C1

C2

0.1

µF

V-

TOUT

TIN

ROUT

1000pF

RIN

GND

5k

Ω

+5V

MAX3311

MAX3313

C1+

C1-

Figure 4. Loopback Test Results at 250kbps

2

µs/div

TOUT

TIN

ROUT

Figure 3. Loopback Test Results at 120kbps

5

µs/div

TOUT

TIN

ROUT

Figure 5. Receiver Positive/Negative Thresholds for INVALID

-2.7V

-0.3V

+2.7V

+0.3V

0

INDETERMINATE

INVALID HIGH

INVALID LOW

INVALID HIGH

INDETERMINATE