UT3221/E

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

2 of 10

www.unisonic.com.tw

QW-R103-128.C

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MARKING

UT3221

UT3221E

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PIN CONFIGURATION

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PIN DESCRIPTION

PIN NO.

UT3221

UT3221E

PIN NAME

DESCRIPTION

1

1

EN

Receiver Enable Control. Drive low for normal operation. Drive high to

force the receiver output (R_OUT) into a high-impedance state.

2

2

C1+

Positive terminal of the voltage doubler charge-pump capacitor.

3

3

V+

+5.5V generated by the charge pump.

4

4

C1-

Negative terminal of the voltage doubler charge-pump capacitor.

5

5

C2+

Positive terminal of inverting charge-pump capacitor.

6

6

C2-

Negative terminal of inverting charge-pump capacitor.

7

7

V-

-5.5V generated by the charge pump.

8

8

RS-232 Receiver 1 Input.

9

9

TTL/CMOS Receiver 1 Output.

10

-

INVALID

Output of the valid signal detector. Indicates if a valid RS-232 level is

present on receiver input logic “1”.

11

11

TTL/CMOS Transmitter 1 Input.

12

-

FORCEON

Drive high to override automatic circuitry keeping transmitter on

13

13

RS-232 Transmitter 1 Output.

14

14

GND

Ground.

15

15

+3.0V ~ +5.5V Supply Voltage.

16

-

FORCEOFF

Drive low to shut down transmitter and on-board power supply. This

over-rides all automatic circuitry and FORCEON (Table 2).

-

10, 12

NC

No connect

-

16

FORCEOFF

Shut off Pump Power and Transmitters. Active low.