Nec B58944 - Datasheet 2021 [verified]

The NEC B58944 is a specialized automotive ECU (Engine Control Unit) driver chip

, typically found in Bosch systems such as the EDC16 diesel engine computer. In some technical documentation and inventory listings, it is cross-referenced or identified as the D43256BGU-70Y , which is a 256K-bit CMOS Static RAM. Key Technical Specifications Manufacturer Package Type SOP-28 (Small Outline Package, 28-pin) Primary Function ECU Driver / Solid State High-Side Relay Memory Specs 32K words x 8 bits (if identified as D43256BGU) Access Time Voltage Supply 4.5V to 5.5V (Standard CMOS) Operating Temp 0°C to 70°C (Standard) Applications and Features Engine Control:

Specifically used as a driver chip for Bosch ECUs in vehicles like Honda, Iveco (EDC16), and various ME7 series modules (e.g., ME7.5, ME7.9.6). Vehicle Repair:

It is frequently replaced during ECU board repairs when the unit fails to communicate or drive engine components properly. High-Side Driving:

Operates as a dual-channel high-side solid-state relay to control power flow to automotive actuators. Data Retention: When used in its RAM capacity, it features low cap V sub cap C cap C end-sub

data retention (minimum 2.0V) and battery backup capabilities. www.dcddcc.com Pinout Overview (SOP-28)

The SOP-28 configuration generally follows standard JEDEC SRAM or driver layouts for 28-pin packages: Address Inputs: cap A sub 0 cap A sub 14 Control Pins: Chip Enable ( modified cap C cap E with bar above ), Output Enable ( modified cap O cap E with bar above ), and Write Enable ( modified cap W cap E with bar above cap V sub cap C cap C end-sub (Pin 28) and cap G cap N cap D www.dcddcc.com

For further procurement or detailed schematics, retailers like Jotrin Electronics

provide updated stock and compatibility lists as of 2024–2026. Jotrin Electronics list of compatible replacement NEC B58944 D43256BGU-70Y BOSCH Auto ECU computer IC

Q2: Can I use a TIP41C instead?

A: Yes, TIP41C (100V, 6A) is acceptable for most linear applications, but check hFE matching. nec b58944 datasheet 2021

Guide: How to Find the Correct Datasheet for "NEC B58944"

Final Recommendation

  1. Abandon the "B58944 2021" search – it is almost certainly a typo or mislabeled component.
  2. Search for 2SB589 – if that matches your 3-pin transistor, use the 2SB589 datasheet (circa 1990s–2000s). The electrical specs will be identical.
  3. If 2SB589 yields nothing, post a clear photo of the component (top and bottom) on electronics forums like EEVblog, Reddit r/AskElectronics, or Badcaps.net. Include the board name/model.

Do you have a photo of the component or the board it came from? If you can describe the markings exactly (e.g., "B58944" in one line, or "B589" over "44"), I can narrow it down further.

I couldn’t find a specific NEC B58944 datasheet from 2021 in my current knowledge base or search results.

A few possibilities to help you find the correct document:

  1. Check the part number – B58944 may be:

    • A custom OEM part number (e.g., for Renesas/NEC, Sharp, or a module manufacturer)
    • An internal marking code rather than a standard commercial datasheet number
    • A misremembered or misread marking (common examples: NEC B5894? B5894A? B58944 might be a date/lot code)

  2. Likely component type – NEC (now Renesas Electronics) used 5‑digit codes for:

    • Microcontrollers (78K series, V850)
    • Power management ICs
    • Display drivers or custom ASICs

  3. Search suggestions:

    • Try searching: "B58944" Renesas or "B58944" NEC
    • Check Renesas official site (NEC merged with Renesas in 2010)
    • Look at Alldatasheet.com, DatasheetArchive, or Octopart
    • Search by package markings + function (e.g., if it’s a 5‑pin regulator, transistor array, etc.)

  4. If you have the device:

    • Share a photo or full marking line (first row, second row)
    • Describe the package (SOP, DIP, QFP, TO‑220, etc.)
    • Mention any surrounding circuit context

If you confirm the exact full part number or share an image of the marking, I can help locate the correct 2021 or later datasheet.

The NEC B58944 is a specialized integrated circuit primarily utilized as an ECU driver within automotive engine control units. It is widely recognized as an equivalent or alternative designation for the $\mu$PD43256BGU-70L, a 256-Kibit static RAM (SRAM) component. Technical Overview Component Type: Integrated Circuit (IC) / SRAM. The NEC B58944 is a specialized automotive ECU

Function: In automotive contexts, it serves as a driver or memory buffer for Engine Control Units (ECUs), often found in Bosch or other European automotive modules. Package Style: SOP-28 (Small Outline Package with 28 pins). Memory Density: 256 Kilobits (32K x 8 bits).

Performance: Typically rated with an access time of 70ns (indicated by the "-70" suffix in its equivalent part number). Application & Repair

The B58944 is frequently referenced in professional automotive repair circles, specifically for:

ECU Refurbishment: Replacing failed driver chips in older vehicle control modules.

Data Storage: Handling critical operational parameters and temporary data within the vehicle's computer system.

While the "2021" designation in your query may refer to updated inventory records or specific 2021 datasheet revisions from distributors like Jotrin Electronics or Elparts, the core technology remains an established standard in legacy automotive electronics. NEC B58944 ECU DRIVER SOP-28 - Inovauto.com

NEC B58944 (often associated with the part number D43256BGU-70Y

a specialized integrated circuit (IC) primarily used as an engine control unit (ECU) driver or memory chip in automotive systems, particularly those manufactured by

. While a specific "2021 datasheet" for this legacy component is not a standard industry publication—as the chip has been in use for decades—it remains a critical part for automotive repair and ECU refurbishment. Overview of the NEC B58944 The B58944 is frequently identified as a SRAM (Static Random Access Memory) Abandon the "B58944 2021" search – it is

chip with a capacity of 256K bits (32K x 8). In the context of automotive electronics, it serves as a high-reliability component within the engine's "brain" to manage real-time data processing for fuel injection, ignition timing, and diagnostics. Key Specifications and Applications Package Type : Typically found in a (Small Outline Package with 28 pins). : Acts as an ECU Driver

or high-speed memory interface for various Bosch engine management systems. Compatibility : Widely used in ECUs for brands such as

, and various European models using systems like Bosch ME7.4.4, ME7.5, and EDC16. Common Failure Point

: It is noted in technical circles as a "easily damaged part" on ECU circuit boards, often requiring replacement when an engine fails to start or displays persistent computer errors. Modern Context (2021 and Beyond)

In recent years, interest in the B58944 datasheet has spiked among independent mechanics and electronics hobbyists. This is largely due to the "right to repair" movement and the increasing cost of replacing entire ECU modules in aging vehicles. Availability

: New-old-stock (NOS) chips can still be sourced through specialized electronics retailers like Jotrin Electronics Repair Services

: Many workshops now offer specific services for desoldering failed B58944 chips and replacing them with fresh ones to restore vehicle functionality without the need for expensive reprogramming of a new unit. Jotrin Electronics or specific voltage requirements for a repair project? B58944 NEC Integrated Circuits (ICs) - Jotrin Electronics

4. If you still need a “prepared piece” (summary table)

Here is a placeholder datasheet template you can fill in as you find the real document:

| Parameter | Value (when known) | |-----------|--------------------| | Manufacturer | NEC / Renesas | | Part number | B58944 (verify) | | Part family | ? | | Package | ? | | Pin count | ? | | Operating voltage | ? | | Supply current | ? | | Key features | ? | | Datasheet release | 2021 (if confirmed) | | Status | ? (Active / EOL) |

What a 2021 Datasheet Would Contain (Hypothetical)

If a real 2021 NEC datasheet for B58944 existed, it would include:

  • Absolute maximum ratings (Vce, Ic, Pd)
  • Electrical characteristics (hFE, Vce(sat), fT)
  • Package dimensions (SOT-23, TO-92, etc.)
  • Typical characteristic curves

But again: No such public document exists for "B58944" from 2021.

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