4-224

MH89792

Preliminary Information

Figure 2 - Pin Connections

Pin Description

Pin #

Name

Description

1E2o

2048kHz Extracted clock (Output). This clock is extracted by the device from the received

signal. It is used internally to clock in data received from RLA and RLB.

D.C. Power (Input) +5V supply

3RxA

Receiver A (Output). The bipolar CEPT signal received by the device at RLA and RLB

inputs is converted to a unipolar format and output at this pin. This pin should be connected

to the positive receive pin of the framer.

4RxB

Receiver A (Output). This pin should be connected to the negative receive gain pin of the

framer and provides a signal of the same format as RxA.

Ground (Input). D.C. power return path.

6RxD

Received Data (Output) This unipolar return to zero format signal is the product of RxA

and RxB logically “OR” ed and is required by some framers.

7RxINV

RxA/RxB inversion (Input). A logic low applied to this pin will invert the outputs RxA and

RxB. A logic high should be applied if no inversion is required.

8

CLKF/

CLKR

E2o phase selection is achieved by use of this pin. A logic low provides E2o with a

falling edge coinciding with the centre of the data bit. A logic high provides E2o with a rising

edge.

9

LOS

Loss of signal (Output). This pin goes low when 128 continuous zeros are received on the

RLA and RLB inputs. When RxINV and LOS are low RxA and RxB are forced high. When

RxINV is high and LOS is low RxA and RxB are forced low. LOS is reset when 64 ones are

received in two dual E1 framer periods.

10

LOSP

Loss of signal Polarity (Input). A logic low applied to this pin will invert LOS. A logic high

should be applied when LOS is required.

11

NC

No connection. This pin is not fitted.

12

RLA

Received Line A (Input). The A wire or Tip Connection of the E1 receive line should be

connected to this pin.

13

RLB

Receive Line B (Input). The B wire or Ring connection of the E1 receive line should be

connected to this pin.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

E2o

VDD

RxA

RxB

VSS

RxD

RxINV

CLKF/CLKR

LOS

LOSP

NC

RLA

RLB

TLA

TLB

NC

NC

NC

TxA

TxB