cf8223a Nippon Precision Circuits Inc, (NPC), cf8223a Datasheet - Page 2

• Manufacturer Part Number: cf8223a
• Description: Fsk Decoder And Dtmf Receiver Ic
• Manufacturer: Nippon Precision Circuits Inc, (NPC)

BLOCK DIAGRAM
PIN DESCRIPTION
1. Shimitt trigger input
Number
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
FSK/DTMF
OSCOUT
PDWN
OSCIN
AGND
RDRC
DOUT
Name
RDET
RING
RDIN
GND
VDD
AGND
TIP
GS
DV
IC
RING
TIP
GS
1
Differential
Discriminator
FSK/DTMF
Amplifier
I/O
I/O
Ol
O
O
O
O
O
O
–
–
I
I
I
I
I
I
VDD
Logic
Circuit
Bias
Tip input. Connected to the telephone line through a protection circuit
Ring input. Connected to the telephone line through a protection circuit
Input-stage amplifier gain-select output. Used to adjust the gain of the input-stage amplifier.
Analog ground output. Internal reference voltage (V
Ring detector input. Used for line reversal and ring signal detection. Connected for ring detection
of attenuated ring signals.
Ring detector RC terminal. Connected to an RC network which sets the ring detector delay time.
Ring detector output. RDRC-input Schmitt-trigger buffer output. LOW-level output when ring
signal is detected.
Power-down control input. LOW-level for normal operation. HIGH-level for power-down state.
In the power-down state, pins AGND, OSCOUT, DOUT, and DV are HIGH.
Ground. Connected to the system ground potential.
Crystal oscillator output. The crystal oscillator element is connected between this pin and
OSCIN.
Crystal oscillator input. The crystal oscillator element is connected between this pin and
OSCOUT.
Test input. Tied LOW for normal operation.
FSK/DTMF discriminator output. HIGH-level output when receiving FSK signal, and LOW-level
output when receiving DTMF signal.
Demodulator output. Demodulated FSK or DTMF signal output. HIGH-level output in power-
down state.
Data trigger output. Data is output on DOUT when this pin goes LOW.
Supply
GND
PDWN
FSK/DTMF
OSCIN
FSK Decoder
DTMF Receiver
Dial Tone
Filter
OSC
Band Pass
Filter
OSCOUT
CF8223A
High Group
Low Group
Filter
Filter
Function
RDIN
DD
/2) output level
Ring Detect
Decoder
Decoder
DTMF
Logic
Logic
FSK
RDRC
NIPPON PRECISION CIRCUITS INC.—2
RDET
DV
DOUT
Pad dimensions
1046
1063
1634
2053
2634
2634
2634
2634
2211
1612
638
176
176
176
176
596
X
[ µ m]
2934
2934
2665
1954
1534
1550
1942
2623
2934
2934
492
226
226
226
226
506
Y