Integrated
Circuit
Systems, Inc.
ICS1660
Incoming Call Line Identification (ICLID) Receiver
with Ring Detection
Description
The
ICS1660
“ICLID” circuit is a monolithic CMOS VLSI
device that decodes and detects the Frequency Shift Keying
(FSK) signals used in caller identification telephone service.
The
ICS1660,
when used in conjunction with some external
components, amplifies, filters and demodulates the FSK
data transmitted from the central office to the telephone
subscriber.
The
ICS1660
detects the first power ring signal and demodu-
lates the 1200 baud FSK data transmitted during the silent
interval between the first and second power ring. The FSK data
is transmitted from the central office switch to the subscriber
line as part of the CLASS service of Calling Number Delivery
(CND). This data is then demodulated, amplified and filtered
by the
ICS1660
and digitally transmitted to the host control-
ler/processor.
The
ICS1660
is designed to be powered by any off-the-shelf
9.0 volt battery. The on-chip 5.0 voltage regulator powers the
host microprocessor and any external circuitry supported by
the
ICS1660.
This portion of the circuit can be overridden by
connecting the V
IN
pin (18) to the V
DD
pin (1) for a common
power supply. A low battery detection circuit is also provided
on-chip and signals the microprocessor on the FSK/BAT pin
(17) when the PWR pin (16) input is pulled low.
Features
•
•
•
•
•
•
Ring Detection
Low Battery Detection
Internal 5V Regulator - can externally source 25mA
FSK Demodulation
Power-down in Standby Mode
Direct Interface to Host Microprocessor or
Microcomputer
Applications
•
•
•
•
•
Telephones
Facsimile Machines
Modems
Telephone Interface Equipment
Stand-alone ICLID products
ICLID Block Diagram
TO LINE
Surge and
Lightning
Protection
TO PHONE
8
Data
2 x 16 LCD
Display
3
Control
Micro-
Controller
KEYPAD
ICS1660
Rng Detect
FSK Demodulation
Signal Conditioning
Low Battery Detect
Power-down
Standby
AC/DC
Adapter
DC
Jack
9VDC
Voltage
Regulation
+5VDC
External
Memory
(RAM/EPROM)
ICS1660RevA100694
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