SM8224B
NIPPON PRECISION CIRCUITS INC.
Dual-Tone Receiver IC
OVERVIEW
The SM8224B is a receiver and decoder that supports the Bellcore TR-NWT-000030 and SR-TSV-002476
standards calling number identification (caller ID) and call waiting dual-tone signals. It has separate caller ID
signal and call waiting signal inputs, which allows the gain for each input to be adjusted independently. It is
fabricated in CMOS and features a power-down function, realizing low power dissipation operation.
FEATURES
s
PINOUT
(Top view)
s
s
s
s
s
s
s
s
TR-NWT-000030 and SR-TSV-002476 standards
(Bellcore)
Call waiting
FSK decoder
High input sensitivity
Independent input gain adjustment for caller ID
signal and call waiting signal inputs
Power-down mode
Crystal oscillator circuit built-in
Single supply operation:4.5 to 5.5V
Molybdenum-gate CMOS process
AGND
TIP
RING
TRQ
GND
OSCIN
OSCOUT
MODE
TEST
DOUT
1
20
DT1
DT2
DTQ
S0
S1
VDD
CDET
CR
DTDET
SM8224B
APPLICATIONS
s
s
s
s
s
Telephones, fax machines and modems that sup-
port pre- and mid-conversation information ser-
vices
Adapters for pre- and mid-conversation informa-
tion service functions
Telephone answering machines
Facsimile machines
Computer peripheral equipment
10
11
STR
ORDERING INFORMATION
D e vice
SM8224BM
SM8224BS
P ackag e
20-pin SSOP
20-pin SOP
NIPPON PRECISION CIRCUITS—1
SM8224B
PACKAGE DIMENSIONS
(Unit: mm)
20-pin SSOP
1.30
±
0.10
7.40 max
7.20
±
0.05
0.20
±
0.05
5.30
±
0.05
7.90
±
0.20
0.62 typ
1.80
±
0.10
2.10 max
0 to 8
0.10
±
0.10
0.68
±
0.12
0.10
0.30
±
0.10
0.65
0.13
M
20-pin SOP
12.75 ± 0.10
0.275 ±
10.31 ± 0.20
7.50 ± 0.10
0.51 ± 0.2 45
0 to 8
0.41 ± 0.05
0.20 ± 0.10
1.27
2.34 ± 0.10
NIPPON PRECISION CIRCUITS—2
0.76 ± 0.25
0.6
±
0.15
0.045
SM8224B
BLOCK DIAGRAM
TIP
Filter
RING
TRQ
DT1
DT2
DTQ
Filter
(2130Hz)
FSK
Demodulator
Output
Circuit
DOUT
Carrier
Detector
CDET
Detector
Circuit
(2130Hz)
Filter
Level
Detector
Time-constant
Circuit
AGND
Bias
Circuit
Filter
(2750Hz)
Detector
Circuit
(2750Hz)
STR
CR
DTDET
Level
Detector
Crystal
Oscillator
Circuit
Power-down
Circuit
OSCIN OSCOUT
MODE S1 S0
VDD GND
NIPPON PRECISION CIRCUITS—3
SM8224B
PIN DESCRIPTION
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Name
AG N D
TIP
RING
TRQ
GND
OSCIN
OSCOUT
MODE
TEST
DOUT
STR
DTDET
CR
CDET
VDD
S1
S0
DTQ
DT2
DT1
I/O
O
I
I
O
–
I
O
I
–
O
O
O
I/O
O
–
I
I
O
I
I
Function
Analog ground output. Internal reference voltage (V
D D
/2) output level
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.
Ground. Connected to the system ground potential.
Cr ystal oscillator input. The crystal oscillator element is connected between this pin and OSCOUT.
Cr ystal oscillator output. The crystal oscillator element is connected between this pin and OSCIN.
When MODE is HIGH, and S1 and S0 are both LOW , the device is in pow er-down state. See table 2.
TEST pin. Set OPEN when nor mal using.
Data output. Demodulated FSK signal output. HIGH level output when C D E T goes HIGH.
Dual-tone confirmation output. Function is selected by S0 and S1. See table 2.
Dual-tone confirmation: Active-LOW output when dual tone detection signal passes through RC time
constant delay circuit.
Dual-tone detector output. HIGH-level output when dual tone is detected.
Dual tone RC time constant circuit connection. The dual tone detection signal passes through the RC
network to generate the S T R signal.
FSK signal carrier detector output. LOW -level when active carrier is detected.
Supply
Function select bit 1. Selects the device mode in combination with S0 and MODE. See table 2.
Function select bit 1. Selects the device mode in combination with S1 and MODE. See table 2.
Dual-tone signal input-stage amplifier output. Used to adjust the gain of the input-stage amplifier.
Dual-tone signal input-stage operational amplifier inverting input
Dual-tone signal input-stage operational amplifier non-inverting input
NIPPON PRECISION CIRCUITS—4
SM8224B
SPECIFICATIONS
Absolute Maximum Ratings
GND = 0V
P arameter
Supply voltage range
Input voltage range
Pow er dissipation
Storage temperature range
Symbol
V
DD
V
IN
P
D
T
stg
Condition
Rating
−
0.5 to 7.0
−
0.3 to V
D D
+ 0.3
44
−
40 to 125
Unit
V
V
mW
°
C
Recommended Operating Conditions
GND = 0V
Rating
P arameter
Supply voltage
Clock frequency
Clock frequency accuracy
Operating temperature
Symbol
V
DD
f
C L K
∆
f
C
T
opr
Condition
min
4.5
–
−
0.1
−
20
typ
–
3.579545
–
–
max
5.5
–
+0.1
85
V
MHz
%
°
C
Unit
Electrical Characteristics
V
DD
= 5.0V ± 0.5V, GND = 0V, f
CLK
= 3.579545MHz, T
a
=
−
20 to 85
°
C unless otherwise noted.
Rating
P arameter
Symbol
Condition
min
Supply current consumption
I
D D
No analog signal input, no output load,
S1 = 0V, S0 = V
D D
, MODE = 0V
No analog signal input, other inputs =
V
D D
or 0V, no output load, S1 = 0V,
S0 = 0V, MODE = V
D D
–
typ
–
max
8.0
mA
Unit
Pow er-down current
MODE, S0, S1 LOW -level input
voltage
MODE, S0, S1 HIGH-level input
voltage
O S C I N L OW -level input voltage
OSCIN HIGH-level input voltage
D O U T, S T R , DTDET, CR, C D E T
L O W -level output current
D O U T, S T R , DTDET, CR, C D E T
HIGH-level output current
TIP, RING, DT1, DT2, MODE, S1,
S0 input leakage current
I
D P D
–
–
15
µA
V
IL1
V
IH1
V
IL2
V
IH2
I
O L
I
O H
I
IN
–
0.7V
D D
–
0.7V
D D
2
–
−
1
–
–
–
–
–
–
–
0.3V
D D
–
0.3V
D D
–
–
−
0.8
1
V
V
V
V
mA
mA
µA
NIPPON PRECISION CIRCUITS—5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
