SP337E

3

REV. 1.0.2

3.3V TO 5V RS-232/RS-485/RS-422 MULTIPROTOCOL TRANSCEIVER

PIN DESCRIPTIONS

Pin Assignments

RS-232

RS-485/RS-422

1

TI3

Input

T3 Driver TTL input

T3 Driver TTL input

This pin has a 400k pull-up to Vcc in both RS-232 and RS-485 modes.

The pull-up is disabled in the SP337EU shutdown mode.

2

TXEN

Input

X*

Only RS-485 mode

This pin has a 400k pull-up to Vcc in both RS-232 and RS-485 modes.

The pull-up is disabled in the SP337EU shutdown mode.

3

TX4

Output

X*

T3(Z) Inverting Output

4

TX3

Output

T3 Driver Output

T3(Y) Non-Inverting Output

5

Vcc

Power

Power Supply Voltage, between 3.3V and 5V

6

TX1

Output

T1 Driver Output

T1(Y) Non-Inverting Output

7

TX2

Output

T2 Driver Output

T1(Z) Inverting Output

8

GND

Power

Ground

9

C1+

Pump

Positive Terminal of Positive Flying Capacitor

10

V+

Pump

Vdd Storage Capacitor

11

C2+

Pump

Positive Terminal of Negative Flying Capacitor

12

C1-

Pump

Negative Terminal of Positive Flying Capacitor

13

C2-

Pump

Negative Terminal of Negative Flying Capacitor

14

V-

Pump

Vss Storage Capacitor

15

RI1

Input

R1 Receiver Input, 5k pull-down

R1(B) Receiver Inverting Input

16

RI2

Input

R2 Receiver Input, 5k pull-down

R1(A) Receiver Non-Inverting Input

17

RI3

Input

R3 Receiver Input, 5k pull-down

R3(A) Receiver Non-Inverting Input

18

RI4

Input

R4 Receiver Input, 5k pull-down

R3(B) Receiver Inverting Input

19

RX1

Output

R1 Receiver Output

20

RX2

Output

R2 Receiver Output

X*

21

RX3

Output

R3 Receiver Output

22

RX4

Output

R4 Receiver Output

X*

23

RX5

Output

R5 Receiver Output

X*

24

RI5

Input

R5 Receiver Input, 5k pull-down

X*

25

RS232/RS485

Input

Mode select, either RS-232 (low) or RS-485/422 (high) mode

26

RXEN

Input

Receiver enable for both RS-232 and RS-485/422 mode (Active low)