{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"DS1305E+T&R","brand":"Analog Devices","brandSlug":"analog-devices","productSlug":"DS1305ETR","canonicalUrl":"https://icboms.com/analog-devices/DS1305ETR","factsUrl":"https://icboms.com/api/mcp/products/DS1305E%2BT%26R","rawCanonicalId":null},"summary":{"shortDescription":"Maxim Integrated DS1305E+T&R, Clock/Calendar RTC, SPI interface, 96B NVSRAM, Alarm/Leap Year/Trickle-Charger, 2V-5.5V supply, 0°C-70°C, 20-TSSOP package, Tape & Reel.","salesMarkdown":"## SPI RTC with onboard NVSRAM and trickle charger The Maxim Integrated DS1305E+T&R is a serial real-time clock/calendar that communicates over SPI, carrying 96 bytes of NVSRAM for user data that survives a main power loss. It includes a trickle-charger for a backup battery or supercap, plus alarm and leap-year compensation. The 2 V to 5.5 V supply range and 0°C to 70°C operating temperature suit it for indoor equipment, instrumentation, and embedded controllers where a battery-backed timebase and a small scratchpad are needed on one SPI bus. ## Timekeeping current and battery life Timekeeping current ranges from 25.3 µA to 81 µA depending on supply voltage. ## 20-TSSOP footprint and surface-mount assembly The 20-TSSOP package (4.40 mm body width) is a standard fine-pitch SOIC footprint. It mounts on the board alongside the MCU and passives, with no special handling beyond normal SMT reflow. The Tape & Reel option suits automated pick-and-place; the Cut Tape variant works for prototypes or small runs. ## Active lifecycle and ROHS compliance The DS1305E+T&R carries an Active product status and ROHS3 compliance. No end-of-life notice or last-time-buy window is in effect. It can be specified into new designs without an obsolescence clock, and the ROHS3 rating covers the current EU exemption scope.","metaTitle":"DS1305E+T&R RTC Clock/Calendar, SPI, 96B NVSRAM, 20-TSSOP","metaDescription":"Maxim DS1305E+T&R SPI real-time clock with trickle charger, 96B NVSRAM, 2V-5.5V supply. Active, ROHS3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["DC-DC Power Modules"],"specifications":{"Type":"Clock/Calendar","Package":"Tape & Reel (TR); Cut Tape (CT)","Features":"Alarm, Leap Year, NVSRAM, Trickle-Charger","Interface":"SPI","Date Format":"YY-MM-DD-dd","Memory Size":"96B","Time Format":"HH:MM:SS (12/24 hr)","Mounting Type":"Surface Mount","Package / Case":"20-TSSOP (0.173\\\", 4.40mm Width)","lifecycle_stage":"eol_hot","Voltage - Supply":"2V ~ 5.5V","Operating Temperature":"0°C ~ 70°C","Supplier Device Package":"20-TSSOP","Voltage - Supply, Battery":"2V ~ 5.5V","Current - Timekeeping (Max)":"25.3µA ~ 81µA @ 2V ~ 5V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$6.58","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$6.58000","currency":"USD"},{"qty":10,"price":"$5.91300","currency":"USD"},{"qty":25,"price":"$5.59040","currency":"USD"},{"qty":100,"price":"$4.84500","currency":"USD"},{"qty":250,"price":"$4.59652","currency":"USD"},{"qty":500,"price":"$4.12444","currency":"USD"},{"qty":1000,"price":"$3.47844","currency":"USD"},{"qty":2500,"price":"$3.30452","currency":"USD"}]},"links":{"datasheetUrl":"https://www.analog.com/media/en/technical-documentation/data-sheets/DS1305.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the difference between DS1305 and DS1307?","answer":"The DS1305 uses an SPI interface, while the DS1307 uses I2C. The DS1305 also includes 96 bytes of NVSRAM and a trickle-charger — the DS1307 has neither. If your MCU has a free SPI port and you need battery-backed user RAM, the DS1305 is the better fit."},{"question":"Does the DS1305E+T&R have a built-in trickle charger?","answer":"Yes, the trickle-charger is an integrated feature. It can charge a supercapacitor or rechargeable battery from the main supply when power is present, and the charged element backs up the RTC and NVSRAM during main power loss."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/analog-devices/DS1305ETR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/analog-devices/DS1305ETR when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}