{"id":7800,"date":"2026-06-27T03:26:31","date_gmt":"2026-06-27T03:26:31","guid":{"rendered":"https:\/\/materialparts.com\/ds1744w-120-3\/"},"modified":"2026-06-27T03:26:31","modified_gmt":"2026-06-27T03:26:31","slug":"ds1744w-120-3","status":"publish","type":"post","link":"https:\/\/materialparts.com\/zh\/ds1744w-120-3\/","title":{"rendered":"DS1744W-120"},"content":{"rendered":"

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

The DS1744W-120 is a 32Kx8 nonvolatile timekeeping RAM from Analog Devices (formerly Maxim Integrated) that integrates a full-function real-time clock, 32KB SRAM, crystal, and lithium energy source in a 28-pin EDIP package, providing unlimited write endurance and 10-year data retention in the absence of power.<\/p>\n

\u4e3b\u8981\u89c4\u683c<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
Memory Size<\/td>\n32KB (32K x 8) SRAM<\/td>\n<\/tr>\n
Write Cycle Time<\/td>\n200 ns<\/td>\n<\/tr>\n
RTC Resolution<\/td>\nSeconds through centuries<\/td>\n<\/tr>\n
RTC Accuracy<\/td>\n\u00b11 minute\/month at 25\u00b0C<\/td>\n<\/tr>\n
Data Retention<\/td>\n10 years (no VCC)<\/td>\n<\/tr>\n
\u7535\u6e90\u7535\u538b<\/td>\n5.0V \u00b110%<\/td>\n<\/tr>\n
Active Current<\/td>\n75 mA max<\/td>\n<\/tr>\n
Standby Current<\/td>\n55 mA max<\/td>\n<\/tr>\n
\u5de5\u4f5c\u6e29\u5ea6<\/td>\n-40\u00b0C to +85\u00b0C<\/td>\n<\/tr>\n
\u5305\u88c5<\/td>\n28-pin EDIP<\/td>\n<\/tr>\n<\/table>\n

\u7279\u70b9<\/h2>\n
    \n
  • 32KB nonvolatile SRAM with RTC in one package<\/li>\n
  • Integrated crystal and lithium energy cell<\/li>\n
  • Unlimited write endurance (SRAM-based)<\/li>\n
  • 10-year data retention without external power<\/li>\n
  • Full-function RTC: seconds, minutes, hours, day, date, month, year<\/li>\n
  • Automatic leap year compensation valid up to 2100<\/li>\n
  • Power-fail write protection with battery switchover<\/li>\n
  • 28-pin EDIP module with built-in lithium source<\/li>\n<\/ul>\n

    \u5e94\u7528<\/h2>\n
      \n
    • Industrial data logging<\/li>\n
    • Embedded time-stamping systems<\/li>\n
    • Point-of-sale terminals<\/li>\n
    • Telecom equipment with time-keeping requirements<\/li>\n
    • Instrumentation and calibration records<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"

      Product Overview The DS1744W-120 is a 32Kx8 nonvolatile timekeeping RAM from Analog Devices (formerly Maxim Integrated) that integrates a full-function real-time clock, 32KB SRAM, crystal, and lithium energy source in a 28-pin EDIP package, providing unlimited write endurance and 10-year data retention in the absence of power. Key Specifications Memory Size 32KB (32K x 8) […]<\/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":[13],"tags":[],"chip_brand":[165],"class_list":["post-7800","post","type-post","status-publish","format-standard","hentry","category-integrated-circuits-ics","chip_brand-adi"],"acf":{"brief_explanation":"32KB NV SRAM with RTC, crystal, lithium cell, 10yr retention, 28-EDIP","date_code":"","package_case":"28-pin EDIP (Embedded DIP with integrated battery)","in_stock":10196,"datasheet":"https:\/\/www.analog.com\/media\/en\/technical-documentation\/data-sheets\/DS1744-DS1744P.pdf","price":"$18.50 @ 1ku","product_introduction":"The DS1744W-120 is a 32K x 8 nonvolatile timekeeping RAM from Analog Devices that integrates a full-function real-time clock (RTC), 32KB of static RAM, a quartz crystal, and a long-life lithium energy source in a single 28-pin EDIP package. The SRAM provides unlimited write endurance compared to EEPROM or Flash, while the integrated lithium cell maintains both the RTC and SRAM data for over 10 years in the absence of external power. The RTC tracks seconds, minutes, hours, days, dates, months, and years with automatic leap year compensation valid through 2100. Power-fail write protection ensures data integrity during VCC transients.","working_principle":"The DS1744W-120 combines a 32K x 8 CMOS SRAM array with a real-time clock and a lithium backup cell in a single package. Under normal VCC operation, the SRAM and RTC operate from the external supply. When VCC falls below the power-fail trip point (VPF), an internal switch automatically connects the lithium cell to maintain the SRAM data and RTC operation, and all inputs are ignored to prevent erroneous writes. When VCC returns above VPF, a power-up recovery period (35 ms max) ensures clean initialization before normal operation resumes. The RTC is accessed through 8 register bytes that overlay the SRAM address space, controlled by a read\/write flag bit. The oscillator runs continuously from the lithium cell, maintaining time accuracy to \u00b11 minute per month at 25\u00b0C. The EDIP package hermetically seals the crystal and lithium cell for long-term reliability.","pin_description":"\n
      Pin<\/th>Name<\/th>Type<\/th>Description<\/th><\/tr>\n
      1-12, 23-26<\/td>A0-A14<\/td>Input<\/td>Address inputs (15-bit for 32K x 8)<\/td><\/tr>\n
      13<\/td>CE2<\/td>Input<\/td>Chip enable 2 (active high)<\/td><\/tr>\n
      14<\/td>GND<\/td>Power<\/td>Ground<\/td><\/tr>\n
      15-22<\/td>DQ0-DQ7<\/td>I\/O<\/td>Data bus (bidirectional)<\/td><\/tr>\n
      27<\/td>WE<\/td>Input<\/td>Write enable (active low)<\/td><\/tr>\n
      28<\/td>VCC<\/td>Power<\/td>Supply voltage (5V \u00b110%)<\/td><\/tr>\n
      21<\/td>CE1<\/td>Input<\/td>Chip enable 1 (active low)<\/td><\/tr>\n
      22<\/td>OE<\/td>Input<\/td>Output enable (active low)<\/td><\/tr>\n<\/table>","application_scenarios":"
        \n
      • Industrial Data Logging:<\/strong> 32KB SRAM with unlimited write endurance and 10-year battery backup for critical process data<\/li>\n
      • Time-Stamping:<\/strong> Integrated RTC with automatic leap year provides timestamps for event logs without external clock chip<\/li>\n
      • Point-of-Sale:<\/strong> Transaction records and system configuration survive power outages with zero data loss<\/li>\n
      • Telecom Equipment:<\/strong> Call detail records and configuration data retained through extended power failures<\/li>\n
      • Calibration Records:<\/strong> Long-term retention of instrument calibration data with time-of-last-calibration tracking<\/li>\n<\/ul>","alternative_models":"\n
        Model<\/th>Manufacturer<\/th>Key Difference<\/th><\/tr>\n
        DS1744P-120<\/td>ADI<\/td>PowerCap module version (34-pin)<\/td><\/tr>\n
        DS1644-120<\/td>ADI<\/td>Same without RTC function<\/td><\/tr>\n
        DS1743W-120<\/td>ADI<\/td>8KB version<\/td><\/tr>\n
        DS1553W-120+<\/td>ADI<\/td>Similar with watchdog timer<\/td><\/tr>\n
        FM33256B-G<\/td>Cypress\/Infineon<\/td>256Kb F-RAM + RTC, SOIC-28<\/td><\/tr>\n<\/table>"},"_links":{"self":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7800","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=7800"}],"version-history":[{"count":0,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/posts\/7800\/revisions"}],"wp:attachment":[{"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/media?parent=7800"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/categories?post=7800"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/tags?post=7800"},{"taxonomy":"chip_brand","embeddable":true,"href":"https:\/\/materialparts.com\/zh\/wp-json\/wp\/v2\/chip_brand?post=7800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}