Nec B58944 Datasheet 2021 Jun 2026
A failed B58944 typically presents as a non-functional injector or solenoid, causing the engine to run poorly (misfire) or not start at all.
: CMOS Static RAM (SRAM) matrix configured alongside a low-dropout (LDO) regulator network.
Suitable for loads up to 2.7A, with Roncap R sub o n end-sub less than 0.5 Ω.
The (often associated with Bosch ECU systems) is a specialized, high-performance integrated circuit (IC) primarily utilized in automotive Engine Control Units (ECUs). Known for its robustness, the B58944 acts as a low-side driver chip, managing crucial powertrain and auxiliary components in modern vehicles. This article provides a comprehensive overview of the NEC B58944 datasheet specifications , its role in automotive systems, and essential application details relevant for repairs and diagnostics as of 2021 and through 2026. 1. Introduction to the NEC B58944
The is an automotive engine drive chip (Integrated Circuit) frequently used in BOSCH engine ECU boards . nec b58944 datasheet 2021
This article provides a comprehensive overview of the NEC B58944, based on its technical characteristics, typical applications, and its role in automotive systems as recognized by industry distributors in 2021. What is the NEC B58944?
If the NEC branded B58944 is unavailable, technicians utilize the fully compatible D43256BGU-70Y or its optimized variant D43256BGU-70YE , ensuring matching access times and pinouts.
The B58944 stores vehicle‑specific data (injector codes, immobiliser passcodes, VIN‑related information). If you replace the chip with a blank or donor SRAM, the ECU will not recognise the vehicle. The correct procedure is:
[Isolate Fault Codes/No-Comm] │ ▼ [Check 5V Regulator Output at Pin 28] ──(No Voltage)──► Check Power Supply/Diodes │ (5V Present) ▼ [Inspect SOP-28 Solder Under Microscope] ──(Cracked)──► Reflow Pin Joints │ (Clean Joints) ▼ [Replace Chip with Virgin NEC B58944] Crucial Bench Tips for Technicians: A failed B58944 typically presents as a non-functional
Finding a single "2021" specific datasheet is rare for this part, as it is an older, specialized automotive component. Technical parameters and inventory details can be requested directly from electronic component suppliers like Jotrin Electronics or ECU Fix Tool .
As of 2021 and moving into 2026, the B58944 remains a "legacy yet essential" part. Because these chips are often custom-made for Tier 1 automotive suppliers like Bosch, they are typically sourced through specialized distributors rather than general consumer electronics retailers.
Though dependent on specific implementations, ICs in this class (such as those described in) are designed with protection mechanisms, including over-temperature protection, short-circuit detection, and reverse-polarity protection. Troubleshooting and Replacing the B58944
Try visiting the NEC (or its successor, Renesas Electronics) website. They often have archives of datasheets for their products. The (often associated with Bosch ECU systems) is
: The engine cranks but will not start because the ECU cannot initialize its boot sequence.
Because it is an SOP-28 SMD component, replacement requires skilled surface-mount soldering techniques (hot air station recommended).
The NEC B58944 is widely identified as a or, in some documented applications, a Darlington transistor array or switching transistor . Based on cross-referencing with vintage equipment service manuals (especially CRT monitors, power supplies, and audio amplification stages from the 1990s and early 2000s), the B58944 typically functions as a medium-power NPN transistor.
Values derived from standard operating conditions at $T_a = 25^\circ C$ unless otherwise noted.
When using a hot-air rework station to desolder the old chip from a multi-layer Bosch PCB, use proper pre-heating. Automotive PCBs act as massive heat sinks; attempting to desolder without a pre-heater can delaminate the copper traces.