Nec B58944 Datasheet Jun 2026

The is a specialized, highly durable integrated circuit (IC) predominantly utilized in automotive Engine Control Units (ECUs) developed by Bosch and other major manufacturers. It serves as a vital parallel Static Random-Access Memory ( SRAM ) chip with a total capacity of 256 Kibibits (Kib) , cross-referencing directly to the industry-standard μPD43256BGU-70L (or -70Y) part number. This chip acts as a fast, volatile data buffer for real-time engine diagnostics, fuel injection mapping, and sensor telemetry within high-demand automotive processing systems. Core Specifications and Functional Overview

The B58944 is often cited as a "damaged-prone" part in automotive circuit boards. When replacing it, technicians should note:

The SOP-28 configuration of the B58944 follows standardized physical form-factor dimensions to ensure tight integration into high-density multi-layer PCBs. Physical Footprint (SOP-28 Specifications) nec b58944 datasheet

Because you can't just buy these at a local hobby shop, they are sourced through niche distributors like Jotrin Electronics Auto-Chips Why It Matters to You

Based on its identical counterpart, the , the B58944 features the following technical characteristics: Feature Specification Memory Type CMOS Static RAM (SRAM) Capacity 256K-bit (32,768 words x 8 bits) Access Time 70 ns (indicated by the "-70" suffix) Package Type 28-pin Plastic SOP (Small Outline Package) Voltage Range 2.7 V to 5.5 V (B version) Data Retention Low VCC data retention down to 2.0 V Key Features for Automotive Use The is a specialized, highly durable integrated circuit

: Frequently used in Honda, Volvo (e.g., XC70, XC90), and Iveco engine management systems. Repair and Replacement

The datasheet includes graphs showing the relationship between collector current and intensity. For engineers designing modifications, the graph is essential for high-frequency tuning. Common Applications The NEC B58944 was a "workhorse" component found in: Core Specifications and Functional Overview The B58944 is

The B58944 operates as a in vehicles from manufacturers like Bosch, Honda, and Nissan. It is found inside the computer boards of models such as the Bosch ME7.4.4, ME7.5, ME7.5.10, ME7.9.6, ME7.9.20, EDC7, and EDC16 series, and has been identified in ECUs like the Nissan X-Trail's EDC16CP33.