DS1338C-33# - 56-Byte NV RAM I2C RTC | Analog Devices
Артикул: DS1338C-33# ✓ АктивенDS1338C-33# Обзор
A real-time clock is a clock and timing IC that maintains time independently of the host processor or system clock. Within the broader semiconductor hierarchy, an RTC belongs to the clock and timing category, sits below timekeeping integrated circuits, and supports embedded systems that require accurate calendar information after reset, power interruption, or loss of system time. The DS1338C-33# combines this timekeeping function with 56 bytes of NV SRAM for retaining small quantities of configuration or system data.
The verified product information identifies an I2C interface, 56-byte NV RAM, full BCD clock/calendar functionality, and automatic end-of-month date adjustment. Its serial interface reduces the number of signal connections required compared with a parallel real-time clock. The clock/calendar records seconds through years, allowing a host microcontroller to query or update time while leaving periodic timekeeping in the dedicated RTC.
The DS1338C-33# is housed in a 16-SOIC package measuring 0.295 inch wide by 7.50 mm as identified in the distributor listing. Its surface-mount construction supports compact embedded assemblies while allowing automated production. The low-power architecture is appropriate for systems that must preserve time and small data records without continuously operating the main processor.
Typical uses include industrial embedded controllers, data-acquisition equipment, connected products, and systems that need an independent time base across resets. It can also serve as a companion timekeeper for a microcontroller-based product while its NV RAM stores limited configuration state. Host firmware must implement the device's register map, I2C address, time format, and any alarm or square-wave functions required by the design.
Designers should verify the complete pin assignment, electrical limits, timing characteristics, oscillator configuration, backup-battery behavior, and recommended decoupling directly against the Analog Devices DS1338 datasheet before layout. A crystal and suitable load components are generally required for accurate timekeeping, while I2C traces should be kept short and the power rails properly decoupled.
This page consolidates the verified manufacturer and distributor information, prices as of 2026-10-28, package details, sourcing links, and selection guidance. It also distinguishes verified drop-in candidates from unverified cross-brand options and flags specification fields that require confirmation from the manufacturer datasheet.
Аналоги без доработки для DS1338C-33# — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
Варианты в этой серии
Модели той же серии, совместимые без доработки с DS1338C-33# (тот же форм-фактор и посадочное место) — отличается по Package, Serial Interface, Device Type.
DS1338C-3#
✅ Прямая заменаУточнить цену
Открыть даташит →DS1338U-18+
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
DS1338C-33# Характеристики
| Device Type | Serial real-time clock and calendar |
| Timekeeping Format | Full binary-coded decimal (BCD) |
| Serial Interface | I2C, 2-wire |
| Nonvolatile RAM | 56 byte |
| Calendar Fields | Seconds, minutes, hours, day, date, month, and year |
| Month Adjustment | Automatic end-of-month adjustment for months with fewer than 31 days |
| Корпус | 16-SOIC (0.295 inch, 7.50 mm width) |
| Тип монтажа | Surface mount |
| Manufacturer | Analog Devices Inc./Maxim Integrated |
Руководство по цоколевке DS1338C-33# в корпусе 16-soic (0.295 inch, 7.50 mm width)
Цоколевка для DS1338C-33# (корпус 16-soic (0.295 inch, 7.50 mm width)). Нумерация выводов, функции и схемы подключения определены в техническом описании производителя. Обратитесь к нему для точного посадочного места и рекомендаций по пайке.
Нет подробных данных о распиновке для DS1338C-33#.
Обратитесь к даташиту для полной конфигурации выводов.
Типичное применение
DS1338C-33# подходит для 6 применениеs: Industrial Embedded Controllers, Data-Acquisition Equipment, Connected Products and IoT Nodes, Battery-Backed Metering, Test and Measurement Instruments, Telecommunications and Network Equipment.
Industrial Embedded Controllers
The DS1338C-33# fits industrial embedded controllers that must preserve a real-time calendar across resets, firmware restarts, or temporary controller interruptions. Its 2-wire I2C interface minimizes connection count, while the dedicated clock/calendar maintains seconds through years independently of the main MCU. The 56-byte NV RAM can retain a small amount of operating state, such as counters, calibration flags, or configuration metadata. According to the Analog Devices product page, the device automatically adjusts the end-of-month date for shorter months, reducing calendar-handling work in firmware.
Рекомендуется
Data-Acquisition Equipment
DS1338C-33# is suitable for data-acquisition systems whose logged events require accurate calendar timestamps even when the acquisition processor is restarted. The RTC provides serial access to seconds, minutes, hours, day, date, month, and year, allowing the host controller to attach a consistent timestamp to each record. Its 56-byte NV RAM is also useful for retaining small counters or acquisition status information, although it is not intended for high-volume storage. The 16-SOIC package fits conventional controller boards and communicates efficiently over the shared I2C bus.
Рекомендуется
Connected Products and IoT Nodes
The DS1338C-33# can support connected products that need a reliable local time base for event scheduling, telemetry, synchronization, or audit trails. Because the clock/calendar operates independently of the application processor, an embedded node can recover valid time after reset instead of waiting for a network time source. I2C allows the MCU to query and update the RTC without dedicating multiple parallel pins. The 56-byte NV RAM provides limited persistence for boot counters or small configuration values, while the verified 16-SOIC package supports compact surface-mount assemblies.
Рекомендуется
Battery-Backed Metering
DS1338C-33# is appropriate for metering equipment where operating schedules and event logs must retain meaningful timestamps during power interruptions. The RTC calendar can continue operating from the device's backup source while the main meter is unpowered, subject to the voltage and current limits in the manufacturer datasheet. Its I2C interface lets the metering MCU read time without a wide parallel bus, and the 56-byte NV SRAM can preserve a limited configuration record. Designers should verify battery-life impact because exact operating and backup currents were not included in the supplied excerpts.
Рекомендуется
Test and Measurement Instruments
The DS1338C-33# provides a compact independent time reference for test and measurement instruments that record events against a calendar date. A controller can obtain the BCD clock/calendar registers through I2C and associate captured measurements with a stable timestamp. The dedicated timekeeping function remains useful when the instrument's main processor is busy, restarted, or synchronized with another device. Its 56 bytes of NV RAM can hold small operating flags, while its 16-SOIC package is compatible with standard surface-mount assembly methods.
Рекомендуется
Telecommunications and Network Equipment
DS1338C-33# can be incorporated into telecommunications or network equipment requiring local event timing, maintenance logs, and boot-time timestamps. The I2C interface allows the system controller to access time through a compact two-wire connection and can help maintain scheduling information during service events. The 56-byte NV RAM can retain a small operational record across resets, complementing rather than replacing larger nonvolatile storage. For network products, engineers should confirm pull-up requirements, bus capacitance, oscillator layout, and backup-source behavior against the current Analog Devices documentation.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для DS1338C-33# — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар | DS1338C-3# | DS1338U-18+ |
|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices |
| Package | 16-SOIC (0.295 inch, 7.50 mm width) | 16-pin NSOIC | 16-SOIC |
| Device Category | Serial real-time clock and calendar | I2C real-time clock with 56-byte NV RAM | Serial real-time clock |
Ключевые отличия
- Integrated retained data storage (против DS1338U-18+)
- Established 3.3 V-class supply designation (против DS1338U-18+)
- Same-family 56-byte NV RAM alternative (против DS1338C-3#)
Заметки по проектированию
Place the DS1338C-33# close to the controller and I2C bus routing, with short traces from SDA and SCL to minimize capacitive loading and susceptibility to ringing. Provide the pull-up resistors required by the system I2C specification, accounting for bus capacitance and the voltage domain. Keep the RTC supply bypass capacitor near the VCC pin and provide a clean ground return. Do not rely on long PCB traces or a distant bulk capacitor to replace local decoupling.
Route the oscillator and crystal connection as a short, compact loop on the component side of the PCB, with a solid ground plane beneath the oscillator area. Keep switching regulators, high-current traces, and digital timing edges away from the crystal pins to reduce noise injection that can degrade time accuracy. Follow the exact crystal load-capacitor values and placement guidance in the Analog Devices DS1338 datasheet; the supplied excerpts do not provide the oscillator frequency or recommended load capacitance.
Validate the complete power architecture before using the RTC as a time source in a battery-backed product. This includes the main supply range, backup-source range, leakage into the backup domain, and the current consumed by the RTC and oscillator. The verified excerpts identify low-power operation but do not provide numeric operating or backup-current values, so battery-life calculations cannot be completed without the current Analog Devices datasheet and the selected power-source implementation.
Do not assume that any DS1338-family ordering code is automatically interchangeable. Check the package drawing, pin names, I2C address, time format, temperature grade, backup-source configuration, and available oscillator or square-wave functions. In particular, DS1338C-3# appears closely related but uses a different ordering grade, while DS1338U-18+ represents a different supply-voltage class. Validate the selected part against the complete manufacturer ordering table before releasing production artwork.
Информация о соответствии
The supplied product and distributor excerpts do not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. These fields remain unknown rather than being inferred from the manufacturer or package alone.
