AS2536 austriamicrosystems, AS2536 Datasheet - Page 7

• Manufacturer Part Number: AS2536
• Description: IC MULTI-STANDARD CMOS TELEPHONE SOIC-28
• Manufacturer: austriamicrosystems

Specifications of AS2536

• Audio Control Type: Volume
• Control / Process Application: Electronic Telephonic Set
• Supply Voltage Range: 3.8V To 5V
• Operating Temperature Range: -25°C To +70°C
• Audio Ic Case Style: SOIC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Data Sheet AS2533-36
Last Number Redial
LNR is a facility that allows resignalling of the last
manually dialed number without keying in all the digits
again. The LNR is repeatable after each off-hook.
The current content of the RAM is overwritten by new
entries.
A manually entered number is automatically stored in the
LNR RAM. The capacity of the RAM is 31 digits. If a
number greater than 31 digits is entered, the LNR facility
will be inhibited (until new entries < 32 digits) and further
entries will be buffered in FIFO.
Pauses can be inserted by pressing the PS key (not
AS2535).
Post dialed digits, i.e. digits manually entered after LNR
has been invoked, are not stored in RAM but buffered in
FIFO.
Repeat Dialing (not AS2535)
The last manually dialed number can be repeated without
going on-hook by pressing the RP key. If a called number
is engaged, pressing the RP key will break the line for 1.6
second (to get a new dial tone) and after a pause the
number will be repeated.
The repeat function is enabled when prior to pressing the
RP key, a number has been dialed, and it can be invoked
an unlimited number of times until next on-hook. During the
1.6 second break the device is in power down mode to
save current.
Recall Function
A recall (R1, R2 or R3 key) activation will invoke a flash
(timed loop break), however, the R1 flash is never
executed in LD mode. R2 and R3 will be executed
independent of the mode.
If recall is the first entry in a digit string, it will be stored in
LNR RAM when digit(s) are entered after the recall.
If the recall key is depressed after a digit string has been
entered or dialed out, the recall will not be stored but
buffered in the FIFO together with subsequently entered
digit.
If pressing the recall key is not followed by digit entries,
the LNR RAM remains intact.
After a recall a 270 ms pause will automatically be
Revision 8.8
Memory Keys (not AS2534)
The keys M1 to M12 are direct memory access keys and
the MR key (AS2533/36 only) is used for abbreviated
dialing.
In the on chip RAM, numbers can be stored. Each number
can contain up to 21 digits (including pauses).
During programming multiple pauses can be inserted by
pressing the PS (not AS2535) or the LNR key. Each pause
inserted within the first 5 entries will automatically be
terminated after 2 seconds whereas pauses inserted after
location 5 in a digit string will halt dialing and can be
terminated manually by pressing the PS (not AS2535) or
the LNR key. The halt function allows in-dialing to an
extension on a PABX.
Example (45678–123 is stored in M1, where – is a
pause/wait and 123 the extension number):
off-hook, wait for dial tone
press M1 (45678 is dialed out)
await dial tone from called PABX
press PS or LNR (123 is dialed out)
Memory dialing is cascadable. However, the content of one
memory must be dialed out before a new can be invoked.
Sliding Cursor Procedure
To accommodate easy and uncomplicated redialing (LNR)
behind a PABX, a sliding cursor protocol is implemented. If
new entries match the previous RAM contents, pressing
the LNR key will dial out the remaining digits.
If there is an error in matching, the LNR will be inhibited
until next on-hook, and the RAM will contain the new
number.
Example (LNR content 912345, where 9 is access code):
off-hook, wait for PABX dial tone
press 9 and wait for external dial tone
press LNR (12345 will be dialed out).
Tone Generator
The tone generator incorporates the DTMF tones, 3 basic
frequencies for the tone ringer and pacifier tones.
DTMF
The DTMF generator provides 8 frequencies, namely:
Memory arrangement
Storable numbers
Direct memory keys
Indirect memories
austriamicrosystems
AS2533/36 AS2534
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AS2535
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