{"id":3313,"date":"2026-06-01T01:11:33","date_gmt":"2026-06-01T01:11:33","guid":{"rendered":"https:\/\/materialparts.com\/ds1302sntr-3\/"},"modified":"2026-06-01T01:11:33","modified_gmt":"2026-06-01T01:11:33","slug":"ds1302sntr-3","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/ds1302sntr-3\/","title":{"rendered":"DS1302SN+T&R"},"content":{"rendered":"

\u4ea7\u54c1\u6982\u89c8<\/h2>\n

The DS1302SN+T&R from Maxim Integrated (now Analog Devices) is a real-time clock (RTC) IC with a 31 x 8 battery-backed static RAM. It uses a simple 3-wire serial interface (CE, I\/O, SCLK) for communication with a host microcontroller. The device keeps track of seconds, minutes, hours, day, date, month, and year with automatic leap-year compensation valid up to 2100. It operates from 2V to 5.5V and supports trickle charging for backup battery management, packaged in an 8-pin SOIC.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
Supply Voltage (VCC1)<\/td>\n2.0V to 5.5V<\/td>\n<\/tr>\n
Backup Voltage (VCC2)<\/td>\n2.0V to 5.5V<\/td>\n<\/tr>\n
Time Accuracy<\/td>\n+\/-2 minutes\/month at 25\u00b0C<\/td>\n<\/tr>\n
Interface<\/td>\n3-wire serial (CE, I\/O, SCLK)<\/td>\n<\/tr>\n
RAM<\/td>\n31 x 8 bits battery-backed<\/td>\n<\/tr>\n
Max Serial Clock Rate<\/td>\n2MHz at 5V<\/td>\n<\/tr>\n
Operating Current<\/td>\n300nA typical (timekeeping, VCC2)<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-40 to 85\u00b0C<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\nSOIC-8 (300mil)<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\nTape & Reel<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • Full BCD-coded clock\/calendar: seconds through year<\/li>\n
  • Automatic leap-year compensation valid up to 2100<\/li>\n
  • 31 x 8 battery-backed general-purpose RAM<\/li>\n
  • 3-wire serial interface for minimal pin count<\/li>\n
  • Dual power pins (VCC1 main, VCC2 backup) with automatic switchover<\/li>\n
  • Programmable trickle charger for backup battery<\/li>\n
  • Ultra-low timekeeping current: 300nA typical<\/li>\n
  • Single-byte and burst-mode data transfer<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • Embedded system real-time clock<\/li>\n
    • Time-stamping in data logging systems<\/li>\n
    • Industrial process control timing<\/li>\n
    • Utility meters and billing systems<\/li>\n
    • Point-of-sale terminal time keeping<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The DS1302SN+T&R from Maxim Integrated (now Analog Devices) is a real-time clock (RTC) IC with a 31 x 8 battery-backed static RAM. It uses a simple 3-wire serial interface (CE, I\/O, SCLK) for communication with a host microcontroller. The device keeps track of seconds, minutes, hours, day, date, month, and year with automatic […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[13,55],"tags":[],"chip_brand":[165],"class_list":["post-3313","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","category-transistors","chip_brand-adi"],"acf":{"brief_explanation":"Real-time clock with 31x8 RAM, 3-wire serial, trickle charge, SOIC-8","date_code":"","package_case":"SOIC-8 (SN) (4.9 x 3.9 x 1.58 mm, 300mil)","in_stock":14135,"datasheet":"https:\/\/www.analog.com\/media\/en\/technical-documentation\/datasheets\/ds1302.pdf","price":"$1.15 @ 1ku","product_introduction":"The DS1302SN+T&R is a real-time clock IC from Maxim Integrated (now Analog Devices) that provides time and date tracking with 31 bytes of battery-backed static RAM. The device uses a simple 3-wire serial interface that requires only three GPIO pins from the host microcontroller, making it ideal for pin-constrained designs. The dual-power supply architecture with automatic switchover ensures uninterrupted timekeeping when the main power fails, while the built-in trickle charger can maintain a rechargeable backup battery. The BCD-coded time registers cover seconds through year with automatic month-end and leap-year correction, simplifying firmware development.","working_principle":"The DS1302 operates as a slave device on a 3-wire serial bus. Communication is initiated by the host pulling CE (chip enable) high, then shifting in a command byte (8 bits) followed by data bytes on the I\/O line, synchronized by SCLK. The command byte specifies the read\/write direction and the target register address. The clock\/calendar registers store time in BCD format, with the oscillator running continuously from either VCC1 or VCC2. An internal power-sense circuit automatically switches to the backup supply (VCC2) when VCC1 drops below VCC2, ensuring uninterrupted operation. The 31 bytes of RAM share the same serial interface and are also battery-backed. The programmable trickle charger connects VCC2 to the backup battery through selectable diode and resistor configurations, controlled via the trickle charger register.","pin_description":"
      Pin<\/th>Name<\/th>Type<\/th>Function<\/th><\/tr>
      1<\/td>VCC2<\/td>Power<\/td>Backup supply input (battery)<\/td><\/tr>
      2<\/td>X1<\/td>Input<\/td>32.768kHz crystal input<\/td><\/tr>
      3<\/td>X2<\/td>Output<\/td>32.768kHz crystal output<\/td><\/tr>
      4<\/td>GND<\/td>Ground<\/td>Ground<\/td><\/tr>
      5<\/td>CE<\/td>Input<\/td>Chip enable (active high)<\/td><\/tr>
      6<\/td>I\/O<\/td>I\/O<\/td>Serial data input\/output<\/td><\/tr>
      7<\/td>SCLK<\/td>Input<\/td>Serial clock input<\/td><\/tr>
      8<\/td>VCC1<\/td>Power<\/td>Main supply (2.0-5.5V)<\/td><\/tr><\/table>","application_scenarios":"
      • Real-time clock for embedded systems requiring persistent time tracking<\/li>
      • Data logging systems needing accurate timestamps for recorded events<\/li>
      • Industrial process controllers with scheduled operation and alarm functions<\/li>
      • Utility meters (electric, gas, water) requiring time-of-use billing<\/li>
      • Security and access control systems with time-stamped event logging<\/li><\/ul>","alternative_models":"
        Manufacturer<\/th>Part Number<\/th>Package<\/th>Notes<\/th><\/tr>
        Maxim\/ADI<\/td>DS1302ZN<\/td>SOIC-8<\/td>Narrow body SOIC-8 variant<\/td><\/tr>
        Maxim\/ADI<\/td>DS3231SN#<\/td>SOIC-16<\/td>TCXO RTC, +\/-2ppm accuracy, I2C<\/td><\/tr>
        ST<\/td>M41T62LC6<\/td>DFPN-12<\/td>Ultra-small, I2C, +\/-5ppm<\/td><\/tr>
        Microchip<\/td>MCP7940N-I\/SN<\/td>SOIC-8<\/td>I2C, 64 bytes SRAM, event detect<\/td><\/tr>
        NXP<\/td>PCF8563BS<\/td>TSSOP-8<\/td>I2C, low power, 240nA<\/td><\/tr><\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/3313","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/comments?post=3313"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/3313\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=3313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=3313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=3313"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=3313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}