PIN DESCRIPTION

Name

Pin Number

Description

DIP24

PLCC28

MOD/DMTF

1

1

MODEM or DMTF Operating Mode Selection.

Also controls write operations to control registers (if MOD/DMTF = 0 and

MC/BC = 0).

MC/BC

2

3

Digital Control Input.

In MODEM mode, it sets transmission mode to main or back channel. It also

permits selection of dialing or control registers programming.

RTS

3

4

Request to Send.

When RTS = 0, the circuit sends an analog signal to the ATO output. The signal

depends on the operating mode selected.

When RTS = 1, the signal sent to ATO is suppressed after its first zero crossing.

When MOD/DMTF = 0 and MC/BC = 0, the RTS pin acts as a clock for serial

data loading into the input register.

ENP

4

5

Serial Register Write Select Input. When ENP = 0, the serial register input is

connected to TxD. When ENP = 1, the register input is connected to PRD.

DGND

5

6

Digital Ground = 0V. All digital signals are referenced to this pin.

TxD

6

7

Digital Input for Transmit or Control Data

PRD

7

8

Digital Input for Control Data. Selected through ENP

XtaIIN

8

10

Crystal Oscillator Input. Can be tied to an external clock generator.

XtaIOUT

9

11

Crystal Oscillator Output

DCD

10

13

Data Carrier Detect Output

RxD

11

14

Digital Receive Data Output

ZCO

12

15

Zero Crossing Rx Digital Output (ringing detection)

RDI

13

16

Analog Output for the Receive Signal after Filtering or Analog Input for the

Amplifier-limiter.

RFO

14

17

Analog Receive Filter Output

RAO2

15

18

A2 Amplifier Output

RAI2

16

20

A2 Amplifier Inverting Input

RAI1

17

21

A1 Amplifier Inverting Input

RAO1

18

22

A1 Amplifier Output

V-

19

23

Negative Supply Voltage : – 5V

±5%

AGND

20

24

Analog Ground = 0 V. Reference Pin for Analog Signals

V+

21

25

Positive Supply Voltage : + 5V

±5%

ATO

22

26

Analog Transmit Output

WLO

23

27

Analog Output for Line Monitoring and Buzzer

ATxI

24

28

Direct Analog Input Transmit Filter

TS7514

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