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ML145428

Asynchronous–to–Synchronous

and Synchronous–to–

Asynchronous Converter

Legacy Device: Motorola MC145428

The ML145428 Data Set Interface provides asynchronous-to-synchronous

and synchronous-to-asynchronous data conversion. It is ideally suited for

voice/data digital telesets supplying an EIA-232 compatible data port into a

synchronous transmission link. Other applications include: data multiplexers,

concentrators, data-only switching, and PBX-based local area networks. This

low-power CMOS device directly interfaces with either the 64 kbps or 8kbps

channel of Motorola’s MC145422 and MC145426 Universal Digital Loop

Transceivers (UDLTs), as well as the MC145421 and MC145425 Second

Generation Universal Digital Loop Transceivers (UDLT II).

• Provides the Interface Between Asynchronous Data Ports and

Synchronous Transmission Lines

• Up to 128 kbps Asynchronous Data Rate Operation

• Up to 2.1 Mbps Synchronous Data Rate Operation

• On-Board Bit Rate Clock Generator with Pin Selectable Bit Rates of

300, 1200, 1400, 4800, 9600, 19200 and 38400 bps or an Externally

Supplied 16 Times Bit Rate Clock

• Accepts Asynchronous Data Words of 8 or 9 Bits in Length

• False Start Detection Provided

• Automatic Sync Insertion and Checking

• Single 5 V Power Supply

• Low Power Consumption of 5 mW Typical

• Application Notes AN943 and AN946

• Operating Temperature Range TA = –40º to +85ºC.

P DIP 20 = RP

PLASTIC

CASE 732

SOG 20 = -6P

PLASTIC

CASE 751D

20

1

20

1

CROSS REFERENCE/ORDERING INFORMATION

MOTOROLA

P DIP 20

MC145428P

ML145428RP

SOG 20

MC145428DW

ML145428-6P

LANSDALE

PACKAGE

Note: Lansdale lead free (Pb) product, as it

becomes available, will be identified by a part

number prefix change from ML to MLE.

PIN ASSIGNMENT

BR1

BRCLK

DL

TxD

TxS

SB

BR3

BR2

BCLK 5

4

3

2

1

10

9

8

7

6

14

15

16

17

18

19

20

11

12

13

CM

DOE

DCO

RESET

RxD

RxS

DCI

DIE

DCLK

BLOCK DIAGRAM

DOE

DIE

DCLK

CM

RESET

DCI

TxS

TxD

DL

BR1-BR3

BCLK

BRCLK

RxD

SB

RxS

DATA

STRIPPER

Tx

FIFO

SYNCHRONOUS

CHANNEL

TRANSMITTER

BAUD

RATE

GEN

CONTROL

DATA

FORMATTER

Rx

FIFO

SYNCHRONOUS

CHANNEL

RECEIVER

DCO