+---\/---+ VCC 1| |28 GND I/O0 2| |27 A14 I/O1 3| |26 A13 I/O2 4| NEC |25 A12 A0 5| B58944 |24 A11 A1 6| |23 A10 A2 7| |22 A9 A3 8| |21 A8 A4 9| |20 A7 A5 10| |19 A6 I/O3 11| |18 I/O7 I/O4 12| |17 I/O6 I/O5 13| |16 I/O5 /WE 14| |15 /OE +--------+
– NEC’s VCRs (Video Cassette Recorders) used custom hybrid ICs for capstan and drum motor drivers. B58944 might appear on main control boards alongside NEC D78C10 microcontrollers.
In automotive module environments, the NEC B58944 is exposed to voltage fluctuations (load dumping) and intensive thermal stress. Symptoms of a Faulty B58944 IC
NEC’s semiconductor division merged with Renesas in 2010. Submit a part number inquiry through Renesas’s customer support portal. Provide photos of the component and any surrounding PCB markings.
Common in EDC7 and EDC16 units for heavy vehicles like Iveco. nec b58944 datasheet
Position the new replacement chip on the pads. Double-check that the Pin 1 orientation dot matches the marking on the circuit board.
No matching results appear in:
According to technical data from UTSOURCE and TDK/EPCOS , the B58944 features standard characteristics suitable for diverse applications. 10 kΩ ± 1% to ± 5% B-Value ( B25/50cap B sub 25 / 50 end-sub B25/100cap B sub 25 / 100 end-sub ) 3950 K (Typical) Tolerance ± 1% to ± 5% (Model dependent) Operating Temperature -55°C to +125°C Maximum Power (P₂₅) ≈ 200 mW Dissipation Factor ( δthdelta sub t h end-sub ) ≈ 3.5 mW/K (in air) Thermal Cooling Time Constant ( τctau sub c ) ≈ 12 s (in air) Lead Type Copper-clad Fe wire, tinned 2.1. The Resistance-Temperature (R/T) Curve
Given the difficulty finding it online, try these methods: +---\/---+ VCC 1| |28 GND I/O0 2| |27
: The B58944 is often sold as an "empty" chip, meaning it does not contain pre-installed program data and must be integrated into the specific board's system architecture.
Always use a gate resistor to dampen oscillations and protect against voltage spikes.
Optimized at 70 nanoseconds (ns) to prevent timing bottlenecks during heavy computational engine cycles.
Since many NEC discrete semiconductors are now "End of Life" (EOL), you might need a cross-reference if the original is unavailable. When looking for an equivalent, prioritize: Symptoms of a Faulty B58944 IC NEC’s semiconductor
Often marked or cross-referenced as μPD43256BGU-70L or D43256BGU-70Y . Type: 256 Kbit (32K x 8) Static RAM (SRAM). Package: SOP-28 (Small Outline Package with 28 pins).
The B58944 is a frequent "point of failure" in aging automotive hardware. Because it handles critical data streams within the ECU, a malfunction can lead to severe engine performance issues, "no-start" conditions, or communication errors with diagnostic tools.
: Monitored internal logic gates disable output stages if ambient operating temperatures cross critical thresholds. Common Diagnostic Failures and Repair Scenarios
NEC B58944 Datasheet: Comprehensive Guide to the 10k NTC Thermistor
Technicians have identified specific failure characteristics for this chip. A faulty B58944 can cause , preventing diagnostic tools from connecting to the ECU.