2-200

MH88628

Preliminary Information

Figure 2 - Pin Connections

Pin Description

Pin #

Name

Description

1TIP

Tip Lead. Connects to the “Tip” lead of subscriber line.

2

RING

Ring Lead. Connects to the “Ring” lead of the subscriber line.

3TF1

Tip Feed 1. Access point for balanced ringing. Normally connects to TF2.

4TF2

Tip Feed 2. Access point for balanced ringing. Normally connects to TF1.

5RF1

Ring Feed 1. Access point for balanced ringing. Normally connects to RF2.

6RF2

Ring Feed 2. Access point for balanced ringing. Normally connects to RF1.

7

LGND

Battery Ground. VBat return path. Connected to system’s energy dumping ground.

8LCA

Current Limit Set (Input). The current limit is set by connecting an external resistor to

ground. For 30mA default current, this pin is tied to GND.

9VBat

Battery Voltage. Typically -48Vdc is applied to this pin.

10

DCRI

DC Ringing Voltage Input. A continuous 120Vdc is applied to this input.

11

RGND

Relay Driver Ground Connection.

12

VRLY

Relay Supply Voltage Connection.

13

RD

Ring Drive (Output). Connects to ring relay coil.

14

SEL1

Select 1 (Input). Refer to Table 5

15

SEL2

Select 2 (Input). Refer to Table 5.

16

ESI

External Signal Input. 12/16kHz meter pulse input.

17

ESE

External Signal Enable. Applies the external signal to the line.

18

AGND

Analog Ground. VDD and VEE return path.

19

NATT

Network Balance AT+T Node. Connects to N1 for a network balance impedance of AT&T

compromise (350

Ω + 1kΩ // 210nF); the device’s input impedance must be set to 600Ω.

This node is active only when NS is at logic high. This node should be left open circuit when

not used.

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

N2

Z900

Z1

Z2

TX

RX

GTX0

GTX1

GRX0

GRX1

ACRI

Z600

NS

SHK

UD

IC

IC

IC

VEE

VDD

TIP

RING

TF1

TF2

RF1

RF2

LGND

LCA

VBat

DCRI

RGND

VRLY

RD

SEL1

SEL2

ESI

ESE

AGND

NATT

N1

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20