ICS1660
Pin Descriptions
PIN NUMBER
DIP SO
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
1
2
3
4
5
6
7
8
9
11
12
13
14
15
16
17
18
NAME
VDD
RING
POSTF
LFILTER
LINEAFILTER
VCOSET
LINEA
LINEB
VSS
FILTER2
FILTEROUT
AMPIN
FILTER3
LINEBFILTER
FILTER1
PWR
FSK/BAT
DESCRIPTION
Supply voltage pin to external circuits. Output of 5.0 volt regulator.
Ring detect output signal to the host microprocessor.
Post loop filter signal used by demodulator.
Loop filter for PLL.
Filter input from line “A.”
Center frequency adjustment pin.
“Tip” input from telephone line.
“Ring” input from telephone line.
Ground.
Active filter pin.
Active filter pin.
Input from active filter.
Active filter pin.
Filter input from line “B.”
Active filter pin.
Logic input signal to switch from low current standby mode.
Multiplexed output signal controlled by PWR pin. In standby mode, this is a
low battery (active low) signal. During FSK demodulation, this is the data line
to the
µP
(mark = high).
Input power supply pin.
18
10
19
20
VIN
NC on SOIC
5
ICS [ INTEGRATED CIRCUIT SYSTEMS ]
