BQ4847MT - RTC Module with CPU Supervisor | Texas Instruments
部品番号: BQ4847MT ✗ 生産終了| 数量 | 単価 | 小計 |
|---|---|---|
| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
BQ4847MT 概要
An RTC module is a clock-and-timing integrated circuit that maintains calendar time independently of a processor’s operating state. This BQ4847MT combines the real-time clock with a CPU supervisor, watchdog-related reset control, NVRAM control, reset interrupts, and battery-low warning functions. It sits within the hierarchy RTC, clock/calendar IC, clock and timing IC, and semiconductor. The integrated battery and crystal simplify the timing subsystem, while the battery-backup switchover circuit helps preserve operation through power interruptions.
The key verified features include seconds-through-years BCD timekeeping, an integrated battery and crystal, an on-chip battery-backup switchover circuit, nonvolatile control for an external SRAM, CPU-supervisor functionality, and battery-low warning features. The product is presented in a 28-DIP module format, making it appropriate for legacy and industrial-style through-hole assemblies rather than compact surface-mount designs. The verified distributor snippet describes the package as 28-DIP and does not provide a verified package dimension set beyond the listed 0.61-inch and 15.49 mm module description.
The BQ4847MT is suited to embedded control, industrial instrumentation, data-acquisition equipment, and legacy embedded systems where power-loss recovery, reset control, and persistent timekeeping are important. Its parallel interface permits direct connection to a processor bus or suitable I/O circuitry. The CPU supervisor provides a hardware reset path that can improve system recovery after a fault, power disturbance, or processor lockup.
Designers should verify the exact pin functions, electrical limits, oscillator behavior, and battery requirements from the manufacturer datasheet before layout or firmware development. The verified data confirms the module and principal functions, but it does not provide a complete pinout, supply-current values, temperature range, or detailed timing characteristics. Those parameters should not be inferred from generic RTC designs.
This page synthesizes the verified distributor and manufacturer-document references, identifies the BQ4847MT’s RTC and CPU-supervisor role, and separates confirmed data from parameters requiring direct datasheet verification.
ドロップイン代替品: BQ4847MT — 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。
クイック比較ツール — 並列比較する代替部品を選択:
この製品に利用可能なドロップイン代替品はありません。
代替品をリクエストBQ4847MT 仕様
| Product Type | RTC module with CPU supervisor |
| Timekeeping Representation | BCD, seconds through years |
| インターフェース | Parallel |
| Package Type | 28-DIP module |
| Module Length | 0.61 inch |
| Module Length | 15.49 mm |
| Integrated Battery | Integrated battery |
| Integrated Crystal | Integrated crystal |
| Battery-Backup Switchover | On-chip battery-backup switchover circuit |
| External SRAM Support | Nonvolatile control for an external SRAM |
| Clock Accuracy | ±1 minute per month |
| CPU Supervisor | Included |
| Watchdog-related Control | Watchdog timer function indicated by product documentation |
| Reset Features | Reset interrupts and reset control indicated by product documentation |
| Battery Monitoring | Battery-low warning |
| Calendar Function | Clock/calendar operation |
| 実装スタイル | Through-hole DIP module |
BQ4847MT 28-dip module ピン配置ガイド
BQ4847MT (28-dip module パッケージ) のピン配置。 ピン番号、機能、接続図はメーカーのデータシートで定義されています。正確なフットプリントとはんだ付けのガイドラインについては、データシートを参照してください。
詳細なピン配置データはありません: BQ4847MT.
詳細は データシート をご参照ください。
主な用途
BQ4847MT の用途: 6 件s: Industrial Embedded Control, Data-Acquisition Equipment, Embedded Instrument Panels, Legacy Processor Systems, Battery-Backed Test Equipment, Communication and Network Equipment.
Industrial Embedded Control
The BQ4847MT fits industrial embedded controllers that must preserve calendar time across an unexpected main-supply interruption while retaining CPU reset supervision. Its integrated battery and crystal remove the need for a separate timekeeping oscillator assembly, while the documented battery-backup switchover supports continued operation from backup power. The 28-DIP module format is useful for through-hole legacy and industrial control boards. Before finalizing the design, verify the device’s exact supply limits, temperature range, reset timing, and external-SRAM interface from the manufacturer datasheet.
おすすめ
Data-Acquisition Equipment
The BQ4847MT is applicable to data-acquisition systems where measurements must retain an accurate timestamp even if the controller is reset or loses its primary supply. The verified BCD seconds-through-years representation and ±1 minute per month accuracy statement provide a defined timekeeping basis, while the CPU supervisor can help recover the processor after a fault. Battery-low warning and external-SRAM backup control can further support long-duration field operation. Confirm backup-battery life and retention behavior against the final system requirements.
おすすめ
Embedded Instrument Panels
The BQ4847MT can support instrument panels and service equipment that need event timestamps, operating-hour records, and recovery after processor reset. The integrated battery and crystal provide autonomous timekeeping, while the CPU-supervisor function adds a hardware-based reset mechanism that can complement software monitoring. Its parallel interface may be convenient for older processor buses and through-hole assemblies. Layout planning must account for the 28-DIP module footprint and should be based on the verified mechanical drawing rather than an inferred package drawing.
おすすめ
Legacy Processor Systems
The BQ4847MT is suited to legacy processor systems that use parallel bus-style timing and through-hole component assembly. Instead of relying on a processor clock for timekeeping, the module can retain calendar time through power changes and provide supervisor-related reset behavior. The external-SRAM control feature may be valuable when the design needs nonvolatile system information to survive a backup-power event. Firmware should use the exact BCD calendar format, interrupt behavior, and status-bit definitions documented by Texas Instruments.
おすすめ
Battery-Backed Test Equipment
The BQ4847MT can provide time and reset supervision in battery-backed test equipment where an unexpected supply interruption must not erase the current time or immediately destabilize the controller. The integrated backup battery and switchover circuit simplify the retention architecture, while the CPU supervisor supports fault recovery after reset conditions. The verified ±1 minute per month accuracy statement is useful for initial timing budgeting. Engineers should still validate capacitor requirements, battery endurance, and power-fail behavior from the manufacturer datasheet.
おすすめ
Communication and Network Equipment
The BQ4847MT can be used in communication equipment requiring persistent event time, processor reset supervision, and backup-power retention. The parallel interface and module construction are particularly relevant to older or industrial communication platforms rather than ultra-compact radio modules. The external-SRAM control function may support retention of network status or configuration data during a power transition. Verify signal levels, bus timing, and reset polarity against the host processor and the complete Texas Instruments datasheet.
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: BQ4847MT — 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 |
|---|---|
| Product Type | RTC module with CPU supervisor |
| Timekeeping | Seconds through years in BCD format |
| Clock Accuracy | ±1 minute per month |
| Interface | Parallel |
| Integrated Battery | Yes |
| Integrated Crystal | Yes |
| Backup Control | On-chip battery-backup switchover and external-SRAM control |
| Supervision | CPU supervisor and reset-related functions |
| Package | 28-DIP module, 0.61 inch / 15.49 mm |
| Brand | Texas Instruments |
主な差別化要因
- Broader system-support function set than a basic RTC （vs Generic basic RTC)
- Integrated timekeeping elements （vs Discrete RTC implementation)
- Backup-oriented architecture （vs Processor-dependent software clock)
- Parallel module architecture （vs Surface-mount serial RTC)
設計ノート
Treat the BQ4847MT backup path as a power-integrity design item, not only an RTC feature. The verified documentation identifies an integrated battery and on-chip battery-backup switchover circuit, but the exact supply thresholds, backup current, and battery endurance are not supplied. Before layout, confirm the main supply range, backup-battery voltage, decoupling requirements, and power-fail behavior in the manufacturer datasheet. Estimated power calculations are not possible from the provided data.
Use the verified 28-DIP module description as the starting point for mechanical design, but obtain the official drawing before placing holes or defining the keep-out area. The distributor data identifies a 0.61-inch, 15.49-mm module, yet the supplied source does not provide pin coordinates, row spacing, or tolerance details. Confirm the pin numbering and package dimensions from the datasheet to prevent board rework and incorrect crystal or battery placement.
Do not substitute a generic RTC solely because it also has a calendar counter. BQ4847MT is documented as a module with integrated battery, integrated crystal, CPU supervisor, reset-related behavior, battery-low warning, and external-SRAM backup control. A replacement must be checked for those functions, parallel-interface timing, supply behavior, reset polarity, and mechanical compatibility. The verified cross-reference results do not identify a confirmed drop-in replacement.
Keep clock and backup-support traces away from noisy switching nodes and high-current return paths. The integrated crystal reduces external oscillator routing, but the RTC still requires a clean supply and appropriate decoupling. Follow the manufacturer’s recommended capacitor placement and grounding arrangement once those values are confirmed. Do not infer capacitor values or oscillator load requirements from generic RTC designs.
コンプライアンス情報
Compliance information was not included in the supplied verified web data or internal database data.
