ELAN AG8889N, AG8889AP Datasheet
CALL WAITING DECODER
I. GENERAL DESCRIPTION
This is a new version of Call Waiting service decoder on the telephone. Call Waiting service works by alerting
a customer engaged in a telephone call to a new incoming call. This way the customer can still receive important
calls while engaged in a current call. The Call Waiting decoder can detect dual tone (2130Hz and 2750Hz) alert
signal and generate a valid signal on the data pins for micro controller.
II. FEATURES
• Compatible with Bellcore special report SR-TSV-002476
• 3.6V ~ 6.0V supply voltage
• Call-Waiting (2130Hz plus 2750Hz) Alert Signal Detector
• Good talkdown and talkoff performance
• Sensitivity compensated by adjusting input OP gain
• Package series --- 14-pin DIP or 16-pin SOP (150 mil)
AG8889AP for 14-pin DIP
AG8889N for 16-pin SOP (150 mil)
AG8889
III. APPLICATION
• Feature phones
• Cordless phones
• Adjunct unit (stand alone)
IV. PIN CONFIGURATION
AG8889AP
TIP
RING
OPO
VREF
PWD
VSS
1
2
3
4
NC
5
6
78
14
13
12
11
10
AG8889N
VDD
DO
NC
NC
NC
OSCI
9
OSCO
TIP
RING
OPO
VREF
NC
PWD
VSS
VDD
1
2
3
4
5
6
710
16
15
14
13
12
11
DO
NC
NC
NC
OSCI
OSCO
* This specification are subject to be changed without notice.
NC
89
NC
8.8.2000
1
V. FUNCTIONAL BLOCK DIAGRAM
OPO
AG8889
CALL WAITING DECODER
TIP
RING
VREF
Vdd/2
Voltage
Reference
Tone
Filter
Detection Block
DO
Clock
Generator
PWDOSCI OSCO
VI. PIN DESCRIPTIONS
Pin I/O Description
TIP I Tip in should be connected with twisted pair
RING I Ring in should be connected with twisted pair
OPO O Output of OP Amp
VREF Reference voltage Vref = 1/2 Vdd
PWD I This pin is normal low enabling chip on normal operation and ready to detect CAS
tone signals.
This active high input sets the chip into power down mode and disable oscillator to
save power.
OSCI I 3.58MHz oscillator in
OSCO O 3.58MHz oscillator out
DO O DO : used as output, this pin determines whether DO signal is valid or not. High is
valid. Normal low.
VDD Power
GND Ground
NC Non connected
VII. FUNCTIONAL DESCRIPTIONS
Call Waiting service works by alerting a customer engaged in a telephone call to a new incoming call. This way the
customer can still receive important calls while engaged in a current call. The CALL WAITING DECODER can detect
CAS(Call-W aiting Alerting Signal 2130Hz plus 2750Hz) and generate a valid signal on the data pin.
The call waiting decoder is designed to support the Caller Number Deliver feature, which is offered by regional Bell
Operating Companies. The call waiting decoder has three blocks, including differential amplifier , tone filter detection block
In a typical application, this IC receives Tip and Ring signals from twisted pairs. The signals as inputs of dif ferential
amplifier, and the dif ferential amplifier sends input signal to a band pass tone filter. Once the signal is filtered, the
digital detection block decodes the information. The output data made available at DO pin.
This IC is used for detecting CAS signals. Once the signal is detected, the detection indication is shown on the data
output DO pin. The DO pin is normal low . When this IC detects 2130Hz and 2750Hz frequency at the same time, then
DO pin goes to high.
* This specification are subject to be changed without notice.
8.8.2000
2
AG8889
CALL WAITING DECODER
DC CHARACTERISTIC
VDD=5V, Vss=0V, T a=25°C, fOSC=3.58MHz
Sym. Description Condition Min. Typ. Max. Unit
VDD operating supply voltage 3.6 6 V
IDD operating supply current 3.3 5 mA
VIL low level input voltage 1.5 V
VIH high level input voltage 3.5 V
VOL low level output voltage load=1mA 0.4 V
VOH high level output voltage load=1mA 4.6 V
Note: 1.both tones in the composite signal have equal amplitude.
2.tone pair is deviated by 0.5%.
3.addes a 0.1uf capacitor between Power and Ground.
AC ELECTRICAL CHARACTERISTIC
(VDD=+5V,Ta=+25°C)
CHARACTERISTIC Min. Typ. Max. Unit
Input sensitivity TIP and RING pins ,Vdd=+5V, Input G=1 -38 dBm
Input frequency tolerance for 2130Hz ±1.2 %
Input frequency tolerance for 2750Hz ±1.2 %
* This specification are subject to be changed without notice.
8.8.2000
3
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