MSAN-108 Zarlink Semiconductor, Inc., MSAN-108 Datasheet - Page 20

• Manufacturer Part Number: MSAN-108
• Description: Applications of The MT8870 Integrated DTMF Receiver
• Manufacturer: Zarlink Semiconductor, Inc.

MSAN-108
With a similar arrangement, a travelling salesman
could access price, delivery and customer status,
enter or delete merchandise orders and retrieve
messages all from the comfort of the customer’s
office (Fig. 23a). A department store could provide
shop-by-phone service to its customers using
telephone keypad data entry (Fig. 23b). Brokerage
firms, utilizing the stock exchange mnemonic listings
could provide trading price information and buy/sell
service via telephone keypad entry.
synthesizer could provide opening and current
trading price, volume of transactions and other
pertinent data.
manufacturer could apply this technique, allowing
users to access and change outgoing and incoming
messages from a Touch-Tone phone.
A PBX manufacturer could offer a feature that
relieves the switchboard attendant from unneccesary
interaction. A call could be answered automatically
and a recording may reply ”Thank you for calling
XYZ. Please dial the extension you wish to contact
or zero for the switchboard“.
called party’s extension in advance it is not
neccesary to wait for the switchboard attendant to
A-64
OUTSIDE SALES
CONSUMER AT
HOME PHONE
CUSTOMER’S
TELEPHONE
PERSON AT
OPTIONAL
DIALER
AUTO
A telephone answering system
Figure 23 - Two Applications Of DTMF Data Communications
If the caller knows the
A voice
(a)
(b)
TERMINATION
TERMINATION
ANSWER/
ANSWER/
SALES WAREHOUSE/OFFICE
forward the call. The attendant could be notified to
intervene if there is no action by the caller say, ten
seconds after the recording ends. This provides a
similar function to a ”Direct Inward Dialling“ (DID)
trunk but without the additional overhead incurred
with renting a block of phone numbers as in the DID
case.
Now that a DTMF receiver is so easy and
inexpensive to implement there are many simple
dedicated uses that become attractive.
home and office application for DTMF receivers is in
a self-contained telephone-line-powered toll call
restrictor similar to the block diagram in Fig. 2a. This
could be installed in an individual telephone or at the
incoming main termination depending on which
phone or phones are to be restricted.
disallowing visitors from making unauthorized long
distance calls, the owner may still desire access to
toll dialling. This could be provided by adding a logic
circuit that disables the toll restrictor upon receiving
a predetermined sequence of DTMF characters (Fig.
16). In this case, the user must enter his password
before dialling a long distance number.
AUTO
AUTO
LINE
CATALOGUE SHOPPING WAREHOUSE
LINE
RECEIVER
RECEIVER
MT8870
MT8870
DTMF
DTMF
Application Note
ORDER ENTRY
ORDER ENTRY
SYNTHESIZER
STOCK/PRICE/
SYNTHESIZER
STOCK/PRICE/
ALGORITHM
COMPUTER
COMPUTER
ALGORITHM
DELIVERY
DELIVERY
SPEECH
SPEECH
A useful
While