{"id":8376,"date":"2026-06-28T13:39:22","date_gmt":"2026-06-28T13:39:22","guid":{"rendered":"https:\/\/ic-vendor.com\/cmx865ad4\/"},"modified":"2026-06-28T13:39:22","modified_gmt":"2026-06-28T13:39:22","slug":"cmx865ad4","status":"publish","type":"post","link":"https:\/\/ic-vendor.com\/es\/cmx865ad4\/","title":{"rendered":"CMX865AD4"},"content":{"rendered":"

Productos<\/h2>\n

The CMX865AD4 from CML Microcircuits is a low-power ITU-T V.23\/V.21 FSK modem IC in a 24-pin TSSOP package. Designed for caller ID, utility metering, and low-data-rate telemetry, it integrates modulator, demodulator, and handshake tone generators with minimal external components.<\/p>\n

Especificaciones<\/h2>\n\n\n\n\n\n\n\n
Modulation<\/td>\nV.23 (1200\/75 bps), V.21 (300 bps FSK)<\/td>\n<\/tr>\n
Velocidad de datos<\/td>\nUp to 1200 bps<\/td>\n<\/tr>\n
Tensi\u00f3n de alimentaci\u00f3n<\/td>\n2.7 V to 3.6 V<\/td>\n<\/tr>\n
Supply Current<\/td>\n3 mA (typ, active)<\/td>\n<\/tr>\n
Interface<\/td>\nC-BUS serial (SPI-compatible)<\/td>\n<\/tr>\n
Paquete<\/td>\nTSSOP-24<\/td>\n<\/tr>\n<\/table>\n

Caracter\u00edsticas<\/h2>\n
    \n
  • V.23 and V.21 FSK modulation\/demodulation<\/li>\n
  • Integrated transmit and receive filters<\/li>\n
  • Programmable tone generators for handshake<\/li>\n
  • Low-power 3 mA active current<\/li>\n
  • C-BUS serial control interface<\/li>\n
  • Caller ID and utility metering application support<\/li>\n<\/ul>\n

    Aplicaciones<\/h2>\n
      \n
    • Caller ID generation and detection<\/li>\n
    • Utility metering (AMR\/AMI)<\/li>\n
    • Low-data-rate telemetry<\/li>\n
    • Home automation communication<\/li>\n
    • Point-of-sale terminal modem<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The CMX865AD4 from CML Microcircuits is a low-power ITU-T V.23\/V.21 FSK modem IC in a 24-pin TSSOP package. Designed for caller ID, utility metering, and low-data-rate telemetry, it integrates modulator, demodulator, and handshake tone generators with minimal external components. Key Specifications Modulation V.23 (1200\/75 bps), V.21 (300 bps FSK) Data Rate Up to […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[19,13],"tags":[],"chip_brand":[171],"class_list":["post-8376","post","type-post","status-publish","format-standard","hentry","category-analog-linear-ics","category-integrated-circuits-ics","chip_brand-maxlinear"],"acf":{"brief_explanation":"V.23\/V.21 FSK modem IC, 1200bps, caller ID, utility metering, TSSOP-24","date_code":"","package_case":"TSSOP-24 (7.80 x 4.40 x 1.00 mm)","in_stock":10317,"datasheet":"https:\/\/www.cmlmicro.com\/products\/cmx865\/","price":"$2.80 @ 1ku","product_introduction":"The CMX865AD4 from CML Microcircuits is a low-power FSK modem IC implementing ITU-T V.23 (1200\/75 bps) and V.21 (300 bps) modulation standards in a 24-pin TSSOP package. Designed specifically for caller ID, utility metering, and low-data-rate telemetry applications, the device integrates the complete transmit and receive signal chain including modulator, demodulator, anti-aliasing and band-pass filters, and programmable tone generators for modem handshake protocols. The C-BUS serial control interface (SPI-compatible) provides simple register-based configuration and data transfer with the host microcontroller. Operating from a 2.7 V to 3.6 V supply with only 3 mA active current and sub-1 \u00b5A power-down current, the device is optimized for battery-powered and energy-constrained applications.","working_principle":"The CMX865AD4 implements FSK (Frequency Shift Keying) modulation and demodulation using digital signal processing. In transmit mode, the modulator generates V.23 mark (1300 Hz) and space (2100 Hz) tones at 1200 bps, or V.21 mark\/space tones at 300 bps, with integrated digital-to-analog conversion and transmit filtering. In receive mode, the incoming analog signal passes through a band-pass filter and is digitized by an internal ADC. A digital demodulator extracts the FSK data using correlation-based detection with carrier and timing recovery. The device also generates and detects standard modem handshake tones including answer tone (2100 Hz) and calling tone. The C-BUS interface provides access to control registers, transmit data buffer, and received data buffer.","pin_description":"
      Pin Group<\/th>Count<\/th>Function<\/th><\/tr>
      VDD\/VSS<\/td>4<\/td>Power supply and ground<\/td><\/tr>
      C-BUS<\/td>4<\/td>Serial interface: CSN, CDATA, RDATA, SCLK<\/td><\/tr>
      TX<\/td>2<\/td>Transmit analog output (TXA, TXN)<\/td><\/tr>
      RX<\/td>1<\/td>Receive analog input (RXA)<\/td><\/tr>
      IRQN<\/td>1<\/td>Interrupt output (active low)<\/td><\/tr>
      XTAL<\/td>2<\/td>Crystal oscillator connections<\/td><\/tr>
      Other<\/td>10<\/td>Connect per datasheet (bias, filter caps)<\/td><\/tr><\/table>","application_scenarios":"
      • Caller ID<\/strong>: Type 1 and Type 2 caller ID detection in PSTN telephone equipment and set-top boxes<\/li>
      • Utility Metering<\/strong>: AMR\/AMI data communication over power line or telephone line in smart meter systems<\/li>
      • Low-Rate Telemetry<\/strong>: Remote data acquisition over PSTN or leased lines at 1200 bps<\/li>
      • Home Automation<\/strong>: Data communication between home automation controllers and utility interfaces<\/li>
      • Point-of-Sale<\/strong>: Low-cost modem function in POS terminals for transaction processing<\/li><\/ul>","alternative_models":"
        Model<\/th>Manufacturer<\/th>Standard<\/th>Rate<\/th>Package<\/th>Notes<\/th><\/tr>
        CMX868<\/td>CML<\/td>V.23\/V.21<\/td>1200 bps<\/td>TSSOP-24<\/td>Newer generation<\/td><\/tr>
        CMX869<\/td>CML<\/td>V.23\/Bell 202<\/td>1200 bps<\/td>TSSOP-24<\/td>Bell 202 support<\/td><\/tr>
        Si2401<\/td>Silicon Labs<\/td>V.23\/V.22<\/td>2400 bps<\/td>QFN-16<\/td>Higher rate, integrated DAA<\/td><\/tr>
        MX923<\/td>MaxLinear<\/td>V.92<\/td>56 kbps<\/td>TQFP-64<\/td>Much higher rate modem<\/td><\/tr>
        XR18910<\/td>MaxLinear<\/td>AFE<\/td>N\/A<\/td>QFN-16<\/td>Analog front-end only<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/posts\/8376","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/comments?post=8376"}],"version-history":[{"count":0,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/posts\/8376\/revisions"}],"wp:attachment":[{"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/media?parent=8376"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/categories?post=8376"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/tags?post=8376"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/ic-vendor.com\/es\/wp-json\/wp\/v2\/chip_brand?post=8376"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}