DS3231SN#T&R - I2C RTC with TCXO | Analog Devices
部品番号: DS3231SN#T&R ✓ 生産中DS3231SN#T&R 概要
A real-time clock, or RTC, is a clock-and-timing IC that keeps track of seconds, minutes, hours, date, and calendar information independently of a system processor. Within the product hierarchy, an RTC is a timing IC, a semiconductor, and a system-support component. Unlike a basic crystal oscillator, an RTC combines a stable time reference with registers, an I2C control interface, calendar logic, and often backup-power support. This makes it suitable for preserving timestamps when the main supply is interrupted.
The DS3231SN#T&R integrates a crystal resonator and temperature-compensated oscillator rather than requiring a discrete crystal and load network. It supports two-wire I2C communication, allowing a host microcontroller to read and program calendar and alarm registers. The available package data identifies a 16-pin, 7.50 mm-wide SOIC surface-mount configuration, while the -40 °C to +85 °C range supports industrial temperature requirements. Battery input allows timekeeping to continue when the primary supply is removed.
The internal oscillator is compensated to reduce frequency variation caused by ambient temperature changes. This improves long-term timekeeping consistency compared with an uncompensated crystal oscillator, particularly in applications where the RTC must retain accurate timestamps during intermittent power loss. The 2.3 V to 5.5 V operating range also supports both 3.3 V and 5 V system rails. Exact initial time accuracy, current consumption, alarm resolution, and electrical timing limits are not included in the supplied excerpts and require confirmation from the manufacturer datasheet.
Typical uses include industrial control systems, data loggers, metering equipment, network appliances, medical instruments, and embedded products that need a timestamp or calendar across power interruptions. A host processor can initialize the clock once, periodically retrieve time over I2C, and use the RTC as a trusted time source after restart. The integrated oscillator also reduces board area compared with a discrete crystal plus oscillator implementation.
The primary design consideration is preserving correct battery-backed operation and power sequencing. The PCB must provide the specified supply and grounding connections, clean I2C routing, and suitable decoupling close to the device. Software should verify time validity after every power restoration instead of assuming that the backup source retained a valid timestamp. Exact capacitor, pull-up, and decoupling recommendations should be taken directly from the manufacturer datasheet.
This page consolidates the verified manufacturer and distributor information for the DS3231SN#T&R, combines pricing available as of 2026-10-29 with package and operating-range details, and provides same-package alternatives plus engineering guidance that helps distinguish a true drop-in replacement from merely similar RTC products.
ドロップイン代替品: DS3231SN#T&R — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: DS3231SN#T&R （同一形状・フットプリント） — 相違点: Package, Mounting Type, Bus Interface, Calendar Function, Device Type.
DS3232SN#T&R
✅ ドロップイン📋 参考代替品（カタログ未掲載）
DS3232SN
✅ ドロップイン📋 参考代替品（カタログ未掲載）
DS3231M+
✅ ドロップイン ⚠️ 仕様未検証価格はお問い合わせください
データシートを見る →DS3234SN#T&R
✅ ドロップイン ⚠️ 仕様未検証📋 参考代替品（カタログ未掲載）
DS3231SN#
✅ ドロップイン価格はお問い合わせください
データシートを見る →DS3231SN#T&R 仕様
| Device Type | Real Time Clock (RTC) IC Clock/Calendar |
| Bus Interface | I2C, 2-wire serial |
| Supply Voltage Range | 2.3 V to 5.5 V |
| Nominal Crystal Frequency | 0.0320 MHz |
| 動作温度範囲 | -40 °C to +85 °C |
| Package Type | 16-pin SOIC |
| Package Width | 7.50 mm |
| Nominal Package Length | 10.285 mm |
| Oscillator Architecture | Integrated temperature-compensated crystal oscillator (TCXO) and crystal |
| Timekeeping Feature | Battery backup |
| Calendar Function | Clock and calendar |
| 実装タイプ | Surface mount |
| RoHS ステータス | Not compliant |
DS3231SN#T&R ピン構成
| ピン 1 | SCL — Serial clock input |
| ピン 2 | SDA — Serial data input/output |
| ピン 3 | RST — Active-low reset input |
| ピン 4 | GND — Ground connection |
| ピン 5 | VCC — Main supply input |
| ピン 6 | GND — Ground connection |
| ピン 7 | VCC — Main supply input |
| ピン 8 | VCC — Main supply input |
| ピン 9 | GND — Ground connection |
| ピン 10 | GND — Ground connection |
| ピン 11 | GND — Ground connection |
| ピン 12 | VCC — Main supply input |
| ピン 13 | SDA — Serial data input/output |
| ピン 14 | SCL — Serial clock input |
| ピン 15 | RST — Active-low reset input |
| ピン 16 | VCC — Main supply input |
主な用途
DS3231SN#T&R の用途: 6 件s: Industrial Data Loggers, Metering and Energy Monitoring, Medical and Laboratory Instruments, Network and Communication Equipment, Automated Control and Robotics, Embedded Consumer Devices.
Industrial Data Loggers
The DS3231SN#T&R fits industrial data loggers that must preserve event timestamps when the primary supply is interrupted. Its battery-backed RTC maintains time while the logger is unpowered, while the integrated temperature-compensated oscillator supports stable operation over the specified -40 °C to +85 °C range. The host controller can retrieve calendar and alarm data through the I2C interface after restart instead of depending on an inaccurate software timer. This arrangement provides a compact 16-pin SOIC implementation without an external crystal and compensation network, although the logger should validate the retained timestamp before treating it as trustworthy.
おすすめ
Metering and Energy Monitoring
The DS3231SN#T&R is suitable for energy meters and monitoring equipment that need repeatable event times across power cycles. Its I2C real-time clock provides a dedicated timekeeping source for measurement records, while the 2.3 V to 5.5 V operating range supports both 3.3 V and 5 V meter architectures. Battery backup allows the device to continue tracking time during a supply interruption, which is useful when a utility event or alarm must retain its original timestamp. The integrated TCXO reduces external timing components, but the meter designer should confirm current consumption and long-term accuracy before finalizing the backup-power budget.
おすすめ
Medical and Laboratory Instruments
The DS3231SN#T&R supports laboratory and medical instruments that must associate measurements, alarms, and maintenance events with accurate calendar timestamps. The specified -40 °C to +85 °C range covers broad industrial environments, while the integrated temperature-compensated oscillator addresses frequency variation as ambient conditions change. A 16-pin SOIC package supports compact, surface-mount construction, and the I2C interface allows a control MCU to initialize and read the clock without dedicating many general-purpose I/O pins. Battery-backed operation helps preserve time during service or power interruptions, although clinical designs must validate retention time and regulatory requirements for their specific equipment class.
おすすめ
Network and Communication Equipment
The DS3231SN#T&R is useful in routers, gateways, and communication equipment requiring event logging independent of the host processor. Its two-wire I2C interface provides an efficient way for a network controller to read synchronized date and time, while the integrated crystal and TCXO eliminate a discrete oscillator implementation. The 2.3 V to 5.5 V range accommodates common equipment rails, and the 16-SOIC footprint simplifies PCB layout. During reboot or rail interruption, the backup-powered RTC can continue maintaining time so log records and diagnostic events retain chronological order, subject to firmware validity checks and verified battery-life conditions.
おすすめ
Automated Control and Robotics
The DS3231SN#T&R can timestamp alarms, schedules, and motion events in automated control and robotic systems. Its integrated temperature-compensated crystal oscillator is beneficial where ambient temperature changes could otherwise affect an uncompensated timing reference, while its -40 °C to +85 °C rating supports industrial equipment. The host processor accesses the clock through I2C, leaving I/O resources available for sensors and actuators. If the controller loses power but retains the RTC backup supply, it can determine the duration of an outage and restore schedules in the correct order. Firmware should nevertheless use the RTC validity flag before treating retained data as authoritative.
おすすめ
Embedded Consumer Devices
The DS3231SN#T&R fits compact embedded consumer products that display or record the date and time, including connected accessories and small appliances. Its I2C interface minimizes connection requirements, while the integrated crystal and TCXO reduce the footprint and assembly effort associated with discrete timing components. Operation from 2.3 V to 5.5 V provides flexibility across 3.3 V and 5 V platforms, and battery backup can preserve time during brief power interruptions. The 16-pin SOIC package is appropriate for conventional surface-mount assembly. Product designers should define how users set the initial time, handle daylight-saving or calendar rules, and verify whether the backup cell is user-replaceable.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: DS3231SN#T&R — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | DS3232SN#T&R | DS3232SN | DS3231M+ | DS3234SN#T&R | DS3231SN# |
|---|---|---|---|---|---|---|
| Package | 16-SOIC | 16-SOIC - same | 16-SOIC - same | 16-SOIC - same | 16-SOIC - same | 16-SOIC - same |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Device Type | I2C real-time clock with integrated TCXO | I2C real-time clock with integrated TCXO | I2C real-time clock with integrated TCXO | I2C real-time clock with integrated TCXO | I2C real-time clock with integrated TCXO | I2C real-time clock with integrated TCXO |
| Supply Voltage Range | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
| Nominal Crystal Frequency | 0.0320 MHz | 0.0320 MHz | 0.0320 MHz | 0.0320 MHz | 0.0320 MHz | 0.0320 MHz |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
| Alarm Features | RTC clock and calendar with battery backup | RTC alarm functionality with added output feature | RTC alarm functionality with added output feature | RTC alarm functionality | Additional alarm functionality | RTC alarm functionality |
| Battery Backup | Yes | Yes | Yes | Yes | Yes | Yes |
主な差別化要因
- Integrated temperature-compensated time reference （vs DS3232SN#T&R)
- No external crystal network required （vs DS3234SN#T&R)
- Compact 16-pin SOIC implementation （vs DS3231M+)
設計ノート
Place the I2C pull-up resistors, input and output decoupling capacitors, and backup-battery network close to the DS3231SN#T&R. Keep the SCL and SDA traces short, route them away from switching-node and high-current paths, and use a continuous ground reference beneath the 16-SOIC footprint. The exact capacitor values and I2C pull-up resistance should follow the manufacturer datasheet, because unsupported values can affect rise time, oscillator startup, or supply noise behavior.
Define the main-supply and backup-battery transition before layout. The RTC is specified for 2.3 V to 5.5 V, but the sequencing limits during battery startup, main-supply removal, and complete power loss must be checked in the manufacturer datasheet. Use a backup source that does not backfeed the main rail, and verify the battery's current draw and end-of-life voltage against the required retention period. Firmware should also invalidate retained timestamps when the hardware cannot prove that backup operation remained continuous.
Preserve the manufacturer's recommended land pattern and pin numbering when replacing DS3231SN#T&R with a 16-SOIC alternative. Although several family members use the same package outline, adding a 32.768 kHz output or extra alarm functions can change how a host uses selected pins. Review the complete pin description, not only the package drawing, and confirm the exposed thermal or electrical requirements before approving a footprint change. Automated package matching alone does not establish functional pin compatibility.
Do not treat the battery-backed clock as proof that its timestamp remains valid after every interruption. Validate the oscillator-startup condition, backup-battery installation, reset behavior, and firmware validity flag. Avoid deriving long-term timestamps from the host's reset-time counter when the DS3231SN#T&R is available. Also check oscillator startup after cold conditions and after replacing the backup cell, since both conditions can affect whether retained calendar data should be trusted.
コンプライアンス情報
The verified component-comparison result identifies the part as not RoHS compliant. No supplied source provides verified REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals statements, so those fields remain unknown.