AS2540Q AMSCO [austriamicrosystems AG], AS2540Q Datasheet - Page 9

• Manufacturer Part Number: AS2540Q
• Description: Remote Controlled Single-Chip-Telephone
• Manufacturer: AMSCO [austriamicrosystems AG]

Data Sheet AS2540
The MF output levels are set to -4/-6dB which should allow
efficient backup dialling under all line conditions. The
TONE/PAUSE ratio is 90ms/90ms. The preemphasis
between low group and high group frequencies is t.m.
2.6dB.
FLASH timing
CPU can control the DPn pin and the MASK-mode of
AS2540 via serial interface.
Tone Ringer
Ring frequency discrimination
The ring frequency discrimination assures that only signals
with a frequency between 13Hz and 70Hz are regarded as
valid ring signals.
When a valid ring signal is present for 102ms continuously,
the ring melody generator is activated and remains active
as long as a valid ring signal is present.
Once the ring melody generator has started, the ring signal
is continuously monitored and the ring melody generator is
instantly turned off according to the momentary presence
of a valid or invalid ring signal until next off-hook.
Revision 3.1
Toner ringer melody
The 3 basic melody frequencies are:
-
-
-
The repetition rate is set to 4 which means that the
sequence of F1, F2, F3, F1, F2, F3 is repeated 4 times
within a second.
Keyboard connections
Double contacts under keys 0-9*#: One contact is
connected to AS2540, the other one to CPU.
MODE
PIN
F1=880Hz
F2=1067Hz
F3=1333Hz
R1
R2
austriamicrosystems
c1
PIN
C1
1
4 5 6
7 8 9
* 0 #
C2
2 3
PIN
C2
C3
PIN
C3
Page 9 of 18
PIN
PIN
R1
R2