DTMF Receivers/Generators
CD22202, CD22203
January 1997
Features
• Central Office Quality
• No Front End Band Splitting Filters Required
• Single, Low Tolerance, 5V Supply
• Detects Either 12 or 16 Standard DTMF Digits
• Uses Inexpensive 3.579545MHz Crystal for Reference
• Excellent Speech Immunity
• Output in Either 4-Bit Hexadecimal Code or Binary
Coded 2-of-8
• Synchronous or Handshake Interface
• Three-State Outputs
• Excellent Latch-Up Immunity
Ordering Information
PART
NUMBER
CD22202E 0 to 70 18 Ld PDIP E18.3
CD22203E 0 to 70 18 Ld PDIP E18.3
TEMP .
RANGE (oC) PACKAGE PKG. NO.
5V Low Power DTMF Receiver
Description
The CD22202 and CD22203 complete dual-tone multiple
frequency (DTMF) receivers detect a selectable group of 12
or 16 standard digits. No front-end pre-filtering is needed.
The only externally required components are an inexpensive
3.579545MHz TV “colorburst’’ crystal (for frequency reference) and a bias resistor. Extremely high system density is
possible through the use of the clock output of a crystal connected CD22202/CD22203 receiver to drive the time bases
of additional receivers. This is a monolithic integrated circuit
fabricated with low-power, complementary symmetry CMOS
processing. It only requires a single low tolerance power
supply.
The CD22202 and CD22203 employ state-of-the-art circuit
technology to combine the digital and analog functions on
the same CMOS chip using a standard digital semiconductor
process. The analog input is preprocessed by 60Hz reject
and band splitting filters and then hard limited to provide
AGC. Eight Bandpass filters detect the individual tones. The
digital post processor times the tone durations and provides
the correctly coded digital outputs. Outputs interface directly
to standard CMOS circuitry and are three-state enabled to
facilitate bus oriented architectures.
Pinout
HEX/B28
IN1633
ED (203 ONLY),
NC (202)
XEN
ANALOG IN
CD22202, CD22203
(PDIP)
TOP VIEW
D1
1
2
3
EN
4
5
V
DD
6
7
V
SS
8
9
18
17
16
15
14
13
12
11
10
D2
D4
D8
CLRDV
DV
ATB
XIN
XOUT
V
SS
Functional Diagram
ATB
XEN
XIN
XOUT
9
13
8
12
11
PREPROCESSOR/
BANDSPLIT FILTER
CLOCK
GENERATOR
ANALOG IN
LOW B/P
FILTERS
HIGH B/P
FILTERS
CHIP
CLOCKS
VOLTAGE
REG./REF.
5107
V
DD
V
SS
6
ED-203
NC-202
15
CLRDV
14
DV
2
HEX/B28
1
D1
18
D2
17
PROCESSING CIRCUITS
DETECTORS AND SIGNAL-
4
INI633
D4
16
D8
3
EN
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
http://www.intersil.com or 407-727-9207
| Copyright © Intersil Corporation 1999
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File Number 1695.3
CD22202, CD22203
Absolute Maximum Ratings Thermal Information
DC Supply Voltage (VDD)(Referenced to VSS Terminal). . . . . . . . 7V
Power Dissipation
TA = 25oC (Derate above TA = 25oC at 6.25mW/oC. . . . . . . . 65mW
Input Voltage Range
All Inputs Except Analog In. . . . . . . . . . . . . . (VDD +0.5V) to -0.5V
Analog in Voltage Range . . . . . . . . . . . . (VDD +0.5V) to (VDD -10V)
DC Current into any Input or Output . . . . . . . . . . . . . . . . . . . . . .±20mA
NOTE: Unused inputs must be connected to VDD or VSS as appropriate.
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation
of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Maximum Junction Temperature. . . . . . . . . . . . . . . . . . . . . . . 175oC
Maximum Junction Temperature (Plastic). . . . . . . . . . . . . . . . 150oC
Maximum Storage Temperature Range . . . . . . . . . . -65oC to 150oC
Maximum Lead Temperature (Soldering 10s). . . . . . . . . . . . . 300oC
Operating Conditions
Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . 0oC to 70oC
Electrical Specifications 0
o
C ≤ TA≤ +70oC, VDD = 5V ±10%
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
Frequency Detect Bandwidth ±(1.5 + 2Hz) ±2.3 ±3.5 % of f
O
Amplitude for Detection Each Tone -32 - -2 dBm Referenced to 600Ω
Minimum Acceptable Twist -10 - +10 dB
Tw ist
60Hz Tolerance - - 0.8 V
High Tone
--------------------------- -=
Low Tone
RMS
Dial Tone Tolerance “Precise” Dial Tone - - 0 dB Referenced to Lower
Amplitude Tone
Talk Off MITEL Tape #CM7291 - 2 - Hits
Digital Outputs (except XOUT) “0” Level, 400µA Load 0 - 0.5 V
“1” Level, 200µA Load VDD -0.5 - V
Digital Inputs “0” Level 0 - 0.3V
“1” Level 0.7V
DD
-VDDV
DD
DD
V
V
Supply Current TA = +25oC - 10 16 mA
Noise Tolerance MITEL Tape #CM7291
(Note 1)
- - -12 dB Referenced to Lowest
Amplitude Tone
Input Impedance VDD≥ VIN≥ (VDD -10) 100kΩ//15pF 300kΩ -
NOTE:
1. Bandwidth limited (3kHz) Gaussian noise.
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