BQ4802YDWRG4 - Y2K Parallel RTC with CPU Supervisor | TI
MPN: BQ4802YDWRG4 ✓ Hoạt độngBQ4802YDWRG4 Tóm tắt
The parallel interface allows a host processor to read and write the RTC through address and data lines rather than a serial bus. This makes the device useful in systems where the host already has a parallel bus but lacks a dedicated wall-clock timebase. The century-based calendar addresses year-2000-related date rollover concerns in systems that must retain a full date across power loss or long service intervals. The CPU supervisor function adds system-reset and warning capability, allowing firmware to respond before an out-of-tolerance supply causes an uncontrolled reset.
External nonvolatile SRAM control is another distinguishing feature. Systems using battery-backed SRAM can place the RTC and memory-control functions under one coordinating controller rather than implementing separate timekeeping and retention supervision. The integration reduces the number of discrete functions required, although the battery backup, crystal connection, supply bypassing, and supervisor reset behavior still require careful design review.
The verified BQ4802YDWRG4 listings specify a 28-pin SOIC measuring 0.295 inch, or 7.50 mm, in width. Heisener reports 5,376 pieces in stock and a unit price of $4.5050 as of 2026-10-28, while LCSC lists the part from $2.2824. Lead time on the Heisener listing is marked to be confirmed, so production schedules should not rely on the stated May 16 to May 21 estimated delivery window.
This page distinguishes the BQ4802Y from the lower-voltage BQ4802L family, identifies verified same-package options for design review, and summarizes application, sourcing, and replacement considerations beyond a distributor stock listing. Because the retrieved data does not include a complete manufacturer pin table, electrical limits, or a manufacturer cross-reference list, unavailable parameters are explicitly marked as DATA_NEEDED rather than inferred.
Bộ thay thế dễ dàng lắp đặt cho BQ4802YDWRG4 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với BQ4802YDWRG4 (cùng hình factor và footprint) — khác nhau ở Package, Calendar Capability, Device Type, Package Width, Supply Voltage.
BQ4802YDWR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →BQ4802LYDWR
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Xem tài liệu →BQ4802YDWRG4 Thông số kỹ thuật
| Device Type | Real-time clock and calendar with CPU supervisor |
| Loại giao diện | Parallel |
| Calendar Capability | Century-based calendar, Y2K-compliant |
| Điện áp cung cấp | 5 V |
| Hộp | 28-pin SOIC, 0.295 inch (7.50 mm) width |
| Kiểu lắp đặt | Surface mount |
| Supply Monitoring | Temperature-compensated reference and comparator |
| Out-of-Tolerance Response | Interrupt warning followed by microprocessor reset |
| External NVSRAM Control | Supported |
| Power Category | Low-power microprocessor peripheral |
| I2C Interface | Not specified in verified data |
Hướng dẫn cấu hình chân BQ4802YDWRG4 28-pin soic, 0.295 inch (7.50 mm) width
Cấu hình chân cho BQ4802YDWRG4 (28-pin soic, 0.295 inch (7.50 mm) width gói). Số thứ tự chân, chức năng và sơ đồ kết nối được xác định trong tài liệu thông số kỹ thuật của nhà sản xuất. Tham khảo nó để biết footprint và hướng dẫn hàn chính xác.
Không có dữ liệu chân cụ thể sẵn có cho BQ4802YDWRG4.
Tham khảo: tài liệu kỹ thuật cho cấu hình chân đầy đủ.
Ứng dụng tiêu biểu
BQ4802YDWRG4 phù hợp cho 6 Áp dụngs: Industrial Control Systems, Point-of-Sale and Transaction Terminals, Copiers and Multifunction Printers, Fax Machines and Office Equipment, Battery-Backed Embedded Systems, Process-Control and Supervisory Modules.
Industrial Control Systems
The BQ4802YDWRG4 fits industrial controllers that need a persistent civil date and time beside a parallel processor bus. Its century-based calendar supports long-lived equipment records, while the 5 V supply and CPU-supervisor functions suit legacy control architectures. The device is placed on the controller CPU bus, with its interrupt and reset outputs connected to system supervisory logic. Compared with adding a separate calendar IC and supervisor, consolidation reduces interconnect count, although the missing operating-temperature and electrical-limit data in the retrieved summary must be confirmed from the manufacturer datasheet before industrial qualification.
Được đề xuất
Point-of-Sale and Transaction Terminals
Point-of-sale terminals benefit from a Y2K-compliant century-based calendar for transaction records, audit logs, and synchronized business events. The BQ4802YDWRG4 provides parallel clock access suited to embedded host processors, and its supply monitor can issue a warning before a controlled microprocessor reset becomes necessary. It is used beside the main processor and nonvolatile storage in a terminal, allowing date information to survive a main power interruption when the required backup source is provided. The verified material does not establish backup-cell life or current limits, so those values must be checked before setting maintenance intervals.
Được đề xuất
Copiers and Multifunction Printers
Copiers and multifunction printers need a real date for job accounting, service logs, scheduled maintenance, and document naming. The BQ4802YDWRG4 is specifically associated with fax machines, copiers, and similar embedded office equipment by the TI product page. Place the parallel RTC beside the equipment controller so jobs can receive a correct timestamp even after a power interruption, and use its supply-monitor warning to distinguish a low-voltage event from a processor fault. Its 28-pin SOIC package also matches the legacy parallel-bus architecture found in many printer-control boards.
Được đề xuất
Fax Machines and Office Equipment
The BQ4802Y family is identified by TI as suitable for fax machines, where calendar accuracy and supervisory reset behavior support reliable document handling and maintenance records. BQ4802YDWRG4 operates through a parallel interface and can be integrated near the main controller, reducing software timing dependence for date queries. Its integrated supply comparison gives the firmware an early warning when the rail drifts outside tolerance, followed by a reset if recovery is not achieved. The design should use the exact 5 V operating condition verified for the Y variant and confirm backup-current requirements before finalizing the power architecture.
Được đề xuất
Battery-Backed Embedded Systems
Battery-backed embedded products can use BQ4802YDWRG4 to coordinate real-time clock data with external nonvolatile SRAM control, a pairing emphasized in the retrieved BQ4802YDWRG4 descriptions. Connecting the RTC's NVSRAM-control interface to a retention-memory circuit allows the host processor to recover time and retained records after a power loss instead of relying on an uncertain network time source. The approach is useful in data loggers and compact industrial controllers, but battery capacity, leakage current, and nonvolatile-memory electrical requirements are not present in the verified summary and must be obtained from the manufacturer documentation.
Được đề xuất
Process-Control and Supervisory Modules
The BQ4802YDWRG4 suits supervisory modules that must report time-of-day events and orderly processor recovery after supply disturbances. The temperature-compensated reference and comparator detect an out-of-tolerance supply, generate an interrupt warning, and then initiate a microprocessor reset according to the TI family description. In an industrial control card, the warning can trigger a controlled event log before reset, while the calendar timestamps subsequent operator actions. Designers should validate reset timing, supply tolerances, and isolation requirements against the full manufacturer datasheet because those numerical limits were not included in the supplied web excerpts.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho BQ4802YDWRG4 — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | BQ4802YDWR | BQ4802LYDWR |
|---|---|---|---|
| Package | 28-SOIC (0.295 inch, 7.50 mm width) | 28-SOIC (0.295 inch, 7.50 mm width) | 28-SOIC (0.295 inch, 7.50 mm width) |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Product Type | Y2K-compliant parallel RTC with CPU supervisor and external NVSRAM control | Y2K-compliant parallel RTC with CPU supervisor and external NVSRAM control | BQ4802L parallel RTC family variant |
| Interface | Parallel | Parallel | Parallel |
| CPU Supervisor | Supply warning, interrupt, and microprocessor reset | Supply warning, interrupt, and microprocessor reset | CPU supervisor functionality indicated by BQ4802 family data |
Bảo phân biệt quan trọng
- Combines calendar, CPU supervision, and external NVSRAM control (vsBQ4802LYDWR)
- Exact Y-variant function and package match (vsBQ4802YDWR)
- Documented distributor availability and pricing (vsBQ4802LYDWR)
Ghi chú thiết kế
Design the BQ4802YDWRG4 rail around the verified 5 V operating condition and confirm the manufacturer's absolute-maximum and supply-tolerance limits before adding capacitance or clamp devices. The family integrates a supply reference and comparator to warn of an out-of-tolerance condition, so rail noise, load transients, and regulator accuracy can determine false reset events. Place local decoupling at the device supply pins and verify the complete power-up and power-down profile against the CPU reset thresholds.
Do not substitute BQ4802LYDWR for BQ4802YDWRG4 solely because both use a 28-pin SOIC footprint. The retrieved data confirms 5 V for the Y variant, while the L variant's exact operating-voltage range is not supplied. Review the complete Y-versus-L electrical comparison, backup-cell requirements, and supervisor timing in the current TI datasheet before treating the change as a PCB-level drop-in replacement.
Use the official 28-pin SOIC land pattern and route the parallel clock interface away from switching-regulator and reset-switch nodes. Although the verified excerpts do not provide the pin table, the package contains clock, control, supervisor, and NVSRAM-related signals, so sensitive routing should be treated as a conventional mixed-signal layout. Keep the crystal and backup-circuit area compact when those optional connections are used, and follow the manufacturer's recommended grounding and bypass configuration.
Thông tin tuân thủ
The supplied verified excerpts identify the manufacturer, function, package, price, and stock but do not state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status. These values remain unknown rather than being inferred from the manufacturer name.
