Nec B58944 Datasheet !!hot!! Jun 2026
Typically 70ns (indicated by the "-70Y" suffix) Key Applications in Automotive Systems
After an extensive search of publicly available technical databases (including NEC Electronics/Renesas archives, distributor datasheet repositories, and general web indexes), no official or third-party datasheet for a component labeled exactly “B58944” could be located. This report therefore provides:
Other 32K x 8 SRAMs in SO-28 packages, provided they meet the 70ns speed and low-power requirements.
Add fresh solder to the pads, then use desoldering wick to clear away the old alloy. Clean the entire area thoroughly with isopropyl alcohol. nec b58944 datasheet
: A failing alternator, degraded battery terminals, or improper jump-starting can breach the chip's absolute maximum input voltage ratings.
The is a specialized, proprietary automotive integrated circuit (IC) predominantly recognized under its standard semiconductor designation, D43256BGU-70Y . Manufactured by NEC Electronics (now part of Renesas Electronics), this device functions as a 32K x 8-bit Static Random-Access Memory (SRAM) . It is widely used in automotive applications, specifically for repairing and rebuilding Engine Control Units (ECUs) and Powertrain Control Modules (PCMs).
Supplied as an empty hardware chip (requires no independent firmware programming; operations are driven completely by the master ECU MCU) Understanding the SOP-28 Pin Configuration Typically 70ns (indicated by the "-70Y" suffix) Key
Common in EDC7 and EDC16 units for heavy vehicles like Iveco.
The is a specialized integrated circuit (IC) primarily used as an SRAM memory chip or driver within automotive Engine Control Units (ECUs), particularly those manufactured by Bosch . It is widely recognized in automotive repair circles as a common point of failure in vehicle computers for brands like Honda, Mercedes-Benz, and Volvo. Key Specifications & Equivalents Part Number: B58944
The NEC B58944 reveals the hidden complexity of modern car electronics. On the surface, it is a simple chip, but its role ties into critical systems of security, performance, and diagnostics. Clean the entire area thoroughly with isopropyl alcohol
: When sourcing this component, it is often found under the combined identifier NEC B58944 D43256BGU-70Y . The "D43256" reference relates to standard 256K-bit High-Speed CMOS Static RAM layouts, indicating that this chip architecture incorporates dedicated volatile memory registers to buffer engine diagnostic codes, temporary operational data, and real-time sensor parameters before sending them to the central processor. Key Technical Specifications & Package Parameters
| Parameter | Specification | | :--- | :--- | | | Bluetooth v2.0 + EDR (Enhanced Data Rate) | | Frequency Range | 2.4 GHz ISM Band (2400 – 2483.5 MHz) | | Interface | UART / HCI (Host Controller Interface) | | Modulation | GFSK (Basic Rate), π/4-DQPSK & 8DPSK (EDR) | | Max Data Rate | Up to 3 Mbps (EDR) | | Operating Voltage | 3.3V (Typical) | | Sensitivity | Typically -85 dBm to -90 dBm | | Transmit Power | Class 2 (typical +4 dBm) or Class 1 with external PA support | | Operating Temp | -20°C to +70°C (Standard Commercial) |
: Constant temperature cycling inside the engine bay degrades internal silicon structures over time.
By providing this detailed information, designers and engineers can quickly reference the key specifications and characteristics of the NEC B58944, making it easier to design and develop high-performance analog circuits.
When the NEC B58944 fails, the vehicle's ECU will typically trigger specific symptoms:
