CD22203 Datasheet | Intersil

Description The CD22202 and CD22203 plete 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 ponents 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, plementary symmetry CMOS processing. It only requires a single low tolerance power supply. The CD22202 and CD22203 employ state-of-the-art circuit technology to bine 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. 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 CD22203E TEMP. RANGE (o C) 0 to 70 0 to 70 PACKAGE 18 Ld PDIP 18 Ld PDIP PKG. NO. E18.3 E18.3 Pinout CD22202, CD22203 (PDIP) TOP VIEW D1 HEX/B28 EN IN1633 VDD ED (203 ONLY), NC (202) VSS XEN ANALOG IN 1 2 3 4 5 6 7 8 9 Functional Diagram 6 PREPROCESSOR/ BANDSPLIT FILTER LOW B/P FILTERS 15 CLRDV 14 HIGH B/P FILTERS DETECTORS AND...