BQ4802YDWG4 - Parallel RTC with CPU Supervisor | Texas Instruments
MPN: BQ4802YDWG4 ✓ NakahandaBQ4802YDWG4 Ulas
A real-time clock is a Clock & Timing integrated circuit that maintains calendar time independently of the host processor. The BQ4802Y family combines the RTC function with CPU supervision and external nonvolatile SRAM control, allowing a system to detect power interruptions and preserve critical state when the primary supply fails. This integration is useful in industrial controllers, embedded systems, data-acquisition equipment, and other designs that require reliable wall-clock time plus power-failure control.
The BQ4802YDWG4 uses a parallel interface and BCD clock format, as shown in the verified distributor and datasheet listings. Its Y2K-compliant design provides century-based calendar information, while the CPU supervisor supports system monitoring and reset-related control functions. External NVSRAM control is an important distinction from basic RTC-only devices because the IC can coordinate backup or nonvolatile memory behavior during power transitions. Exact operating voltage limits, current consumption, oscillator accuracy, temperature range, and supervisor timing values were not supplied in the verified data and require confirmation from the manufacturer datasheet.
Typical implementation places the BQ4802YDWG4 beside the host processor, backup battery, external NVSRAM, and system reset circuitry. The parallel bus allows the processor to read calendar and time registers during normal operation, while the supervisor provides a hardware path for power-failure detection. Designers should verify signal levels, battery backup behavior, reset timing, and NVSRAM interface requirements against the complete Texas Instruments datasheet before production release.
Because the part is a clock-and-timing IC rather than a power semiconductor, SOA data is not applicable. For BQ4802YDWG4 sourcing, compare authorized inventory, package variant, datasheet availability, and lifecycle status rather than relying only on a generic cross-reference result. The verified listing from Heisener reported 3,520 pieces at a reference unit price of $7.8255, while Rochester Electronics reported the part in stock; these figures are distributor observations rather than a universal market price.
Mga alternatibo na pwedeng ilagay na BQ4802YDWG4 — parehas na package, pin-to-pin na katugmang. Hindi kasama ang mga bahagi ng iba't-ibang package na nangangailangan ng pagpapaayos ng PCB.
Variante sa Seri na ito
Katulad na modelo sa serye na katugma sa pagpasok BQ4802YDWG4 (parehas na form factor at footprint) — pagkakaiba sa Product Type, Package, Package Width.
BQ4802YDW
✅ Drop-InMagkontak para sa presyo
Tingnan ang Datasheet →BQ4845YS-A4TR
✅ Drop-InMagkontak para sa presyo
Tingnan ang Datasheet →BQ4802YDWG4 Mga Spesipikasyon
| Product Type | Y2K-compliant parallel real-time clock with CPU supervisor and external NVSRAM control |
| Manufacturer | Texas Instruments |
| Clock IC Type | RTC |
| Uri ng Interface | Parallel |
| Clock Format | BCD |
| Volte ng Pagbibigay | 5 V Vcc |
| Packhaging | 28-SOIC |
| Package Width | 0.295 in (7.50 mm) |
| Uri ng Pagpapasok | Surface mount |
| Calendar Support | Century-based Y2K-compliant calendar |
| Time-of-Day Support | Real-time clock with BCD time and calendar data |
| CPU Supervisor | Yes |
| External NVSRAM Control | Yes |
| Reported Distributor Inventory | 3,520 pieces |
| Reported Reference Unit Price | $7.8255 per piece |
| Reported Delivery Timing | March 8 to March 13; year not specified |
Gabay sa Pin Configuration ng BQ4802YDWG4 0.295 in (7.50 mm)
Pin configuration para sa BQ4802YDWG4 (0.295 in (7.50 mm) package). Ang pagnunumero ng pin, mga function, at connection diagram ay tinukoy sa datasheet ng manufacturer. Sumangguni dito para sa eksaktong footprint at mga alituntunin sa soldering.
Wala ng detalyadong pinout data na magagamit para sa BQ4802YDWG4.
Sumangguni sa datasheet para sa buong pin configuration.
Tipikal na mga Gamit
BQ4802YDWG4 ay nararapat para sa 6 aplikasyons: Industrial Embedded Controllers, Data-Acquisition Equipment, Power-Failure-Aware Control Systems, Communications and Network Equipment, Battery-Backed Security and Access Systems, Automotive and Transportation Control Electronics.
Industrial Embedded Controllers
The BQ4802YDWG4 fits industrial embedded controllers that need calendar time independent of the host microcontroller and hardware supervision during supply disturbances. Its verified Y2K-compliant parallel RTC and CPU-supervisor functions combine timekeeping with power-failure awareness, while the 28-SOIC package supports compact surface-mount assembly. The design should use the manufacturer’s recommended backup-battery, reset, and decoupling arrangement, then validate reset timing and state-retention behavior across power cycles.
Inirekomenda
Data-Acquisition Equipment
The BQ4802YDWG4 is appropriate for measurement systems where timestamps must remain consistent when the main controller is reset or temporarily unavailable. Its BCD parallel interface makes the time registers convenient for processor-based logging, and the CPU supervisor provides a hardware monitoring path. External NVSRAM control can support retention of calibration or acquisition metadata. Because the verified data does not provide oscillator accuracy or supply-current limits, measurement timing and battery life must be calculated from the official datasheet.
Inirekomenda
Power-Failure-Aware Control Systems
The BQ4802YDWG4 can support systems that must detect supply degradation and place critical information into nonvolatile storage before power loss. The verified description confirms CPU-supervisor and external-NVSRAM-control functions, which help coordinate orderly shutdown or state preservation. Designers should examine the exact supervisor threshold, response delay, reset behavior, and NVSRAM write timing in the Texas Instruments datasheet; those values are not present in the supplied distributor snippets.
Inirekomenda
Communications and Network Equipment
The BQ4802YDWG4 can provide timekeeping and power monitoring in communications equipment where event logs and reboot diagnostics benefit from real calendar data. Its parallel interface allows integration with processor buses, and the external NVSRAM control can help preserve diagnostic information during unexpected supply loss. The verified data identifies a 5 V Vcc part and 28-SOIC package, but it does not establish protocol timing, isolation, or network-specific qualification; those requirements need separate verification.
Inirekomenda
Battery-Backed Security and Access Systems
The BQ4802YDWG4 can support access-control, alarm, and event-logging systems that need timestamps and controlled shutdown behavior. The century-based calendar helps record dates correctly, while the CPU supervisor and NVSRAM control provide hardware resources for preserving state if the primary rail fails. The verified data does not state backup-battery voltage, current consumption, or alarm timing, so battery selection and security-level compliance require separate manufacturer and standards documentation.
Inirekomenda
Automotive and Transportation Control Electronics
The BQ4802YDWG4 may be evaluated for transportation electronics where calendar logging and power-state monitoring are useful, subject to qualification review. Its verified package is 28-SOIC surface mount, and the integrated CPU supervisor can assist system reset management. However, the supplied data does not confirm AEC-Q100 qualification, automotive temperature range, vibration performance, or automotive supply criteria, so it should not be treated as an automotive-qualified part without an official declaration.
Inirekomenda
Buod ng mga Inirekomendang Produkto
Impormasyon ng Talumpati sa Engineering for BQ4802YDWG4 — ikabit, gabay sa disenyo, at impormasyon ng pagsunod sa kautusan.
Paunawang Hanapin
Ikabit sa Mga Alternatibo
| Parametro | Ito ang Producto | BQ4802YDW | BQ4845YS-A4TR |
|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 28-SOIC | 28-SOIC family context; exact package verification required | 28-SOIC |
| Clock Type | Real-time clock | BQ4802Y family RTC | Parallel real-time clock |
| Interface | Parallel | Parallel family context | Parallel |
Pangunahing mga Pagkakaiba
- Integrated RTC and supervision (kumpara saBQ4845YS-A4TR)
- Y2K-compliant calendar positioning (kumpara saBQ4845YS-A4TR)
- BCD parallel interface (kumpara saBQ4845YS-A4TR)
- Known distributor reference (kumpara saBQ4845YS-A4TR)
Talaan ng Disenyo
Use the manufacturer’s 28-SOIC land pattern and confirm pin 1 orientation before routing the parallel bus. Keep the RTC, supervisor, and NVSRAM-related traces away from noisy switching nodes and provide a clean return path for the digital ground. Because the verified material identifies the package but not the complete pinout, do not release a PCB footprint until the official mechanical drawing and pin table have been checked.
Design the 5 V supply and backup-power paths around the exact datasheet limits, including allowed voltage tolerance, current consumption, and power-fail behavior. The verified listing only states 5 V Vcc; it does not provide current or dropout data. Validate the backup capacitor, battery connection, and NVSRAM write-enable timing in a hardware simulation and in power-cycle testing rather than assuming that any voltage variation is tolerated.
Do not treat the G4, YDWG, or tape-and-reel suffix as automatically interchangeable without checking the orderable part number. Verify the exact temperature grade, package, reel orientation, and manufacturer status. Also avoid confusing the BQ4802Y with a generic serial RTC: the verified device is a parallel, BCD-format RTC with CPU-supervisor and external-NVSRAM-control functions, so register maps and bus timing are critical.
Route the parallel interface as a short, controlled digital bus and account for processor input capacitance, bus direction changes, and any required pull devices only after checking the datasheet. The verified data does not provide setup, hold, or access-time values, so those parameters must be obtained before selecting pull-ups, bus buffers, or processor speed. A logic analyzer should verify read cycles after power-up and after supervisor reset events.
Impormasyon ng Pagsunod sa Kautusan
The supplied verified results do not provide compliance declarations. RoHS, REACH, AEC-Q100, lead-free, halogen-free, and conflict-minerals status must be confirmed from the current Texas Instruments documentation.
