NXP Semiconductors MC34905CS5EKR2

Overview

MC34905CS5EKR2 from NXP Semiconductors (formerly Freescale) is a second-generation System Basis Chip (SBC) integrating a 5.0 V MCU power regulator, ISO 11898-2/5 high-speed CAN transceiver, single LIN 2.1 interface, four configurable wake-up I/Os, and SPI-based diagnostics. It operates across -40°C to +125°C and targets automotive ECU power management with fail-safe state machine control and SMARTMOS technology.

For engineers reviewing the MC34905CS5EKR2 datasheet, MC34905CS5EKR2 pinout, MC34905CS5EKR2 application, or MC34905CS5EKR2 equivalent, this page delivers verified functional identity, validated 32-pin SOIC exposed-pad package mapping, confirmed CAN/LIN timing compliance, real-world LP-mode current specs (≤65 µA), and two manufacturer-validated alternative parts for ECU design continuity.

Technical Context

The MC34905CS5EKR2 implements a hierarchical power architecture: VSUP1 powers internal logic and VDD regulation, while VSUP2 supplies the embedded 5 V-CAN driver and VAUX regulator. Its fail-safe state machine monitors VDD undervoltage, overcurrent, watchdog timeout, and RST pin integrity - asserting SAFE (active-low open-drain) on fault detection.

It supports ISO 11898-5 CAN bus wake-up at baud rates from 40 kb/s to 1.0 Mb/s and LIN 2.1 master/slave operation with programmable termination. Wake-up sources include CAN/LIN activity, I/O transitions, SPI messages, and VDD overcurrent - all configurable in multiple Low-Power (LP) modes with ≤65 µA quiescent current (VDD ON, -40°C to 25°C).

Key Specifications

Pinout & Package

MC34905CS5EKR2 uses a 32-pin SOIC package with exposed thermal pad (Pb-free, EK suffix). Pin layout is footprint-compatible with MC34903/4/5 family variants.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar System Basis Chip applications.

Compared with MC34905CS5EKR2, MC33905CDLR2 offers reduced feature set at lower cost but sacrifices VAUX and MUX-OUT diagnostics, while FS4100QBATR adds ASIL-B safety architecture at the expense of non-drop-in packaging and higher BOM cost.

Availability

MC34905CS5EKR2 is available at Aetrix Electronics and suitable for automotive body control modules, engine control units, ADAS sensor hubs, and electric power steering systems requiring stable component supply across extended temperature and voltage ranges.

Supply support for MC34905CS5EKR2 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications.

The MC34905CS5EKR2 belongs to NXP's System Basis Chip product line, designed specifically for automotive electronic control units requiring integrated power regulation, high-speed CAN, LIN communication, and hardware-level fail-safe monitoring.

FAQ

What is the maximum continuous output current of the VDD regulator in MC34905CS5EKR2?

The MC34905CS5EKR2 VDD regulator delivers up to 150 mA continuously without an external PNP transistor. With an external ballast transistor, it supports up to 200 mA total output current while sharing thermal load. The device includes overcurrent detection with a programmable wake-up threshold of 1.0–3.0 mA in LP mode and thermal shutdown at 160°C to protect against sustained overload conditions. This capability ensures reliable MCU power delivery in demanding automotive environments.

Does MC34905CS5EKR2 support both CAN and LIN simultaneously?

Yes, MC34905CS5EKR2 supports concurrent CAN and LIN operation. Its integrated ISO 11898-2/5 high-speed CAN interface and single LIN 2.1 transceiver operate independently - CAN handles high-priority vehicle network messaging while LIN manages low-cost sensor/actuator communication. The device allows simultaneous wake-up from either bus and provides separate RXD/TXD and RXD-L/TXD-L pins, enabling full-duplex interaction with both protocols without resource contention or timing conflict.

What is the quiescent current of MC34905CS5EKR2 in Low-Power mode with VDD enabled?

In Low-Power mode with VDD enabled, MC34905CS5EKR2 draws ≤65 µA at -40°C to +25°C ambient (VSUP ≤18 V), including oscillator current for cyclic sense and watchdog functions. At +125°C, current rises to ≤85 µA. This ultra-low consumption enables extended key-off monitoring in automotive ECUs while maintaining full diagnostic visibility via SPI and wake-up responsiveness from CAN, LIN, or I/O transitions - critical for meeting OEM battery drain specifications.

How does the SAFE pin function in MC34905CS5EKR2?

The SAFE pin in MC34905CS5EKR2 is an open-drain active-low output that asserts LOW within microseconds upon detection of critical faults: VDD undervoltage (<4.75 V), watchdog timeout, RST pin malfunction, or thermal pre-warning (≥140°C). It directly drives MCU reset circuits and can trigger external safety relays. Unlike software-based alerts, SAFE operates autonomously in hardware, ensuring deterministic fail-safe behavior even if the MCU is unresponsive - a core requirement for ISO 26262-compliant system architectures.

Is MC34905CS5EKR2 compatible with external PNP transistors for VDD current boosting?

Yes, MC34905CS5EKR2 supports external PNP pass transistors for VDD current boosting via its VE (emitter) and VB (base) pins. When implemented, the device shares load current between its internal regulator and the external transistor using a ballast ratio (K = 1.5–2.5), reducing thermal stress and enabling up to 200 mA total output. The design requires proper heatsinking and resistor biasing per Freescale Application Note AN3743; MC34905CS5EKR2 maintains full regulation accuracy and overcurrent protection during ballasted operation.