www.lansdale.com

Page 7 of 11

LANSDALE Semiconductor, Inc.

ML145442, ML145443

15

16

11

RxA2

RxA1

TxD

–

+

AAF

S/H

MODULATOR

LOW–BAND

BPF

HIGH–BAND

BPF

AC

AMP

SMOOTHING

FILTER

CARRIER

DETECT

DEMOD

–

+

3

5

1

17

18

CD

RxD

DSI

TxA

Exl

(a) Originate/Channel 1 Mode (MODE = High, LB = Low)

(b) Answer/Channel 2 Mode (MODE = Low, LB = Low)

15

16

11

RxA2

RxA1

TxD

–

+

AAF

S/H

MODULATOR

LOW–BAND

BPF

HIGH–BAND

BPF

AC

AMP

SMOOTHING

FILTER

CARRIER

DETECT

DEMOD

–

+

3

5

1

17

18

CD

RxD

DSI

TxA

Exl

15

16

11

RxA2

RxA1

TxD

–

+

AAF

S/H

MODULATOR

LOW–BAND

BPF

HIGH–BAND

BPF

AC

AMP

SMOOTHING

FILTER

CARRIER

DETECT

DEMOD

–

+

3

5

1

17

18

CD

RxD

DSI

TxA

Exl

(c) Originate/Channel 1 Mode and Analog Loopback State (MODE = High, LB = Low)

–

+

AAF

S/H

MODULATOR

LOW–BAND

BPF

HIGH–BAND

BPF

AC

AMP

SMOOTHING

FILTER

CARRIER

DETECT

DEMOD

–

+

3

5

1

17

18

CD

RxD

DSI

TxA

Exl

15

16

11

RxA2

RxA1

TxD

(d) Answer/Channel 2 Mode and Analog Loopback State (MODE = Low, LB = Low)

Figure 4. Basic Operating Modes

Issue b