NXP Semiconductors MC34905CS3EK

Overview

MC34905CS3EK from NXP Semiconductors (formerly Freescale) is a System Basis Chip (SBC) integrating a 3.3 V MCU power regulator, ISO 11898-2/5 high-speed CAN transceiver, single LIN 2.1 interface, four configurable wake-up I/O pins, and SPI-controlled diagnostics. It operates across -40°C to +125°C and targets automotive ECU power management with fail-safe state machine control.

For engineers reviewing the MC34905CS3EK datasheet, MC34905CS3EK pinout, MC34905CS3EK application, or MC34905CS3EK equivalent, key selection criteria include its 3.3 V VDD output capability, integrated CAN/LIN dual-bus support, LP-mode quiescent current ≤35 μA at 125°C, and SOIC-32 exposed-pad package with validated pin compatibility across the 34903/4/5 family.

Technical Context

The MC34905CS3EK implements a SMARTMOS-based power management architecture with independent VSUP1/VSUP2 inputs, enabling separate battery monitoring and CAN driver supply. Its fail-safe state machine enforces deterministic response to VDD undervoltage, watchdog timeout, or RST pin faults via open-drain SAFE output.

Functional operation includes three low-power modes: VDD OFF (≤50 μA), VDD ON with cyclic sense (≤85 μA), and debug mode (VDBG = 8–10 V). Wake-up sources include CAN bus activity, LIN transitions, I/O pin edges, SPI messages, and VDD overcurrent detection - all configurable via SPI registers.

Key Specifications

Pinout & Package

MC34905CS3EK uses a 32-pin SOIC package with exposed thermal pad (Pb-free EK suffix), footprint-compatible with MC34903/4/5 family variants. Pin assignments are validated per Figure 8 and Table 4 of Document MC34903_4_5 Rev. 4.0.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC34905CS5EK/R2 and MC34904C3EK/R2, the MC34905CS3EK uniquely delivers 3.3 V MCU regulation with integrated LIN 2.1 - enabling compact, single-chip solutions for mixed-bus automotive nodes without sacrificing low-power performance or fail-safe integrity.

Availability

MC34905CS3EK 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 ranges and long production lifecycles.

Supply support for MC34905CS3EK 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 automotive, industrial, and IoT applications, delivering secure, energy-efficient silicon solutions.

The MC34905CS3EK belongs to NXP's System Basis Chip product line, designed specifically for automotive electronic control units requiring integrated power regulation, CAN/LIN communication, and hardware-level functional safety features.

FAQ

What is the maximum continuous output current of the VDD regulator in MC34905CS3EK?

The MC34905CS3EK VDD regulator delivers up to 150 mA continuously without external components. With an external PNP transistor implemented for ballasting, total output current increases to 200 mA while maintaining thermal stability. This is confirmed in Table 6 (Static Electrical Characteristics) of the MC34903_4_5 Rev. 4.0 datasheet, where ILIM = 150 mA (min) and VDROP-B ≤ 500 mV at 200 mA load. The MC34905CS3EK supports this configuration via VE and VB pins.

Does MC34905CS3EK support both high-speed and fault-tolerant CAN modes?

Yes, the MC34905CS3EK supports both ISO 11898-2 (high-speed CAN, up to 1 Mbps) and ISO 11898-5 (fault-tolerant CAN, 40 kbps–125 kbps) modes. Its integrated CAN physical layer includes bus fault diagnostics, local and bus failure detection, and fail-safe operation - all documented in Sections 51–56 of the MC34903_4_5 Rev. 4.0 datasheet. The MC34905CS3EK achieves this through dedicated CANH/CANL/SPLIT pins and internal protection circuitry.

How many wake-up sources does MC34905CS3EK support in low-power mode?

The MC34905CS3EK supports five distinct wake-up sources in low-power mode: CAN bus activity, LIN bus transitions, edge-triggered signals on any of the four configurable I/O pins (I/O-0 to I/O-3), SPI message reception, and VDD overcurrent detection. This is explicitly stated in the "Features" section and elaborated in Section 35 ("LP Modes") of the MC34903_4_5 Rev. 4.0 datasheet. Each source can be individually enabled/disabled via SPI configuration registers.

What is the purpose of the MUX-OUT pin on MC34905CS3EK?

The MUX-OUT pin on MC34905CS3EK provides SPI-selectable analog monitoring of internal parameters including VDD, VSENSE, VAUX, temperature, and current sense signals. It features an integrated switchable pull-down resistor for VDD current measurement and connects directly to an MCU's ADC input. This functionality is defined in Table 4 (Pin Definitions) and detailed in Section 59 ("Serial Peripheral Interface") of the MC34903_4_5 Rev. 4.0 datasheet. The MC34905CS3EK uses MUX-OUT to enable real-time health diagnostics without additional external circuitry.

Is MC34905CS3EK pin-compatible with other devices in the 34903/4/5 family?

Yes, the MC34905CS3EK is footprint-compatible with all members of the MC34903/4/5 family, including MC34903S, MC34904, and MC34905S variants, using the same 32-pin SOIC exposed-pad package. This is confirmed in Figure 8 ("Pin Connections") and the "Device Variations" tables (Tables 1–3) of the MC34903_4_5 Rev. 4.0 datasheet. Pin compatibility enables design reuse across different feature sets - e.g., swapping MC34905CS3EK for MC34904C3EK removes LIN while retaining identical layout.