2-160

MH88620IN

Preliminary Information

Figure 2 - Pin Connections

Pin Description

Pin #

Name

Description

1TIP

Tip Lead. Connects to the TIP lead of the subscriber line

2RING

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.

7LGND

8LCA

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

shown in Table 5. For 70mA default current, this pin is tied to -5V.

Battery Voltage: Typically -48V dc is applied to this pin.

10

RS1

Ring Sense Resistor Connection 1. See Figure 7a.

11

RGND

Ring Driver Ground Connection.

12

VRLY

Relay Supply Voltage Connection

13

RRD

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

14

RNGC

Ring Relay Control (Input)

15

RS2

Ring Sense Resistor Connection 2. See Figure 7a

16

TRD

Test Relay Drive (Output): Connects to test relay coil.

17

TRC

Test Relay Control (Input).

18

AGND

19

NC

No Connection: Reserved.

20

N1

Network Balance Node 1. An external network balance impedance can be connected

between N1 and AGND. See Fig 4. for complex impedances. N2 no connection.

21

N2

Network Balance Node 2. See Fig 4. N2 connects to GND for 600

Ω balance. N1 no

connection.

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

N2

NC

Z1

Z2

TX

RX

GTX0

GTX1

GRX0

GRX1

NC

NC

NC

SHK

IC

IC

IC

IC

VEE

VDD

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

TIP

RING

TF1

TF2

RF1

RF2

LGND

LCA

VBAT

NC

RGND

VRLY

RRD

RNGC

NC

TRD

TRC

AGND

NC

N1