NXP Semiconductors MC34903CS5EK

Overview

MC34903CS5EK from NXP Semiconductors (formerly Freescale) is a System Basis Chip (SBC) integrating a 5.0 V MCU power regulator, ISO 11898-2/5 high-speed CAN transceiver, 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 and industrial ECU power management with fail-safe state machine control.

For engineers reviewing the MC34903CS5EK datasheet, MC34903CS5EK pinout, MC34903CS5EK application, or MC34903CS5EK equivalent, this page delivers verified functional identity, validated pin roles, confirmed low-power mode behavior (≤65 μA in LP VDD ON), exact CAN/LIN timing compatibility (40 kb/s–1 Mb/s, J2602-2), and real-world substitution guidance for ECU design continuity.

Technical Context

The MC34903CS5EK implements a SMARTMOS-based power management architecture with dual supply inputs (VSUP/1 and VSUP2), integrated 5.0 V VDD regulator (150 mA native, extendable via external PNP), and embedded CAN physical layer compliant with ISO 11898-2 and -5. Its fail-safe state machine monitors VDD undervoltage, overcurrent, watchdog timeout, and RST integrity to assert SAFE (active-low open-drain).

It supports three low-power modes: VDD OFF (≤35 μA), VDD ON with monitoring (≤65 μA), and cyclic sense operation enabled by internal oscillator (5–9 μA). Wake-up sources include CAN bus activity, LIN transitions, I/O edge detection, SPI message, and VDD overcurrent - all programmable via SPI register mapping.

Key Specifications

Pinout & Package

MC34903CS5EK uses a 32-pin SOIC package with exposed pad (Pb-free, RoHS-compliant), footprint-compatible with MC34903S, MC34904, and MC34905 family members. Pin functions are validated per Freescale 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 MC34903CS5EK, MC33903CD5EK offers superior low-power performance and broader voltage tolerance but requires package and pinout redesign, while TC358749XBG provides higher integration at the cost of LIN compatibility and diagnostic flexibility - making MC34903CS5EK optimal for cost-sensitive, LIN-enabled automotive and industrial modules requiring proven field reliability.

Availability

MC34903CS5EK is available at Aetrix Electronics and suitable for automotive body control modules, industrial motor drive controllers, robotics actuator nodes, and smart sensor hubs requiring stable component supply across extended temperature and voltage ranges.

Supply support for MC34903CS5EK 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 acquired Freescale in 2015 and maintains full product support, documentation, and qualification for the MC34903 family. NXP is a global leader in automotive and industrial semiconductors with AEC-Q100 qualified portfolio.

The MC34903CS5EK belongs to NXP's System Basis Chip product line, designed specifically for automotive and industrial electronic control units requiring integrated power management, CAN/LIN communication, and hardware-level fail-safe operation in harsh environments.

FAQ

What is the maximum continuous output current of the VDD regulator in MC34903CS5EK?

The MC34903CS5EK provides 150 mA continuous output current from its internal 5.0 V VDD regulator. When paired with an external PNP pass transistor (connected via VE, VB, VBAUX, and VCAUX pins), the total deliverable current increases to 200 mA with K = 1.5–2.5 ballast ratio - enabling higher MCU or peripheral loads without thermal derating. This capability is confirmed in Table 6 of the MC34903_4_5 datasheet.

Does MC34903CS5EK support both CAN and LIN simultaneously?

Yes, MC34903CS5EK supports simultaneous CAN and LIN operation. As a member of the MC34903S variant (indicated by "S" in the part number), it integrates one LIN 2.1 interface (with dedicated TXD-L, RXD-L, LIN, and LIN-T pins) alongside full ISO 11898-2/5 CAN functionality. The device allows concurrent bus activity, independent wake-up from either bus, and separate SPI-configurable diagnostics for each interface.

What is the quiescent current of MC34903CS5EK in low-power mode with VDD enabled?

In low-power mode with VDD enabled (LP VDD ON), the MC34903CS5EK draws ≤65 μA at VSUP ≤18 V and -40 to 25 °C, as specified in Table 6 of the MC34903_4_5 datasheet. This includes active VDD undervoltage and overcurrent monitoring, SPI accessibility, and wake-up capability from CAN, LIN, or I/O transitions - making it suitable for always-on ECU nodes requiring sub-100 μA standby consumption.

How does the SAFE pin function in MC34903CS5EK?

The SAFE pin in MC34903CS5EK is an open-drain, active-low output that asserts LOW upon detection of any critical fault: VDD undervoltage/overvoltage, watchdog timeout, RST pin malfunction, thermal pre-warning (140 °C), or internal state machine error. It remains asserted until cleared by a valid SPI command or power cycle. This hardware-level fail-safe mechanism operates independently of MCU firmware, ensuring deterministic safety response in MC34903CS5EK-based systems.

Is MC34903CS5EK pin-compatible with other devices in the 34903/4/5 family?

Yes, MC34903CS5EK is footprint-compatible with all MC34903, MC34904, and MC34905 variants in the 32-pin SOIC exposed-pad package, as explicitly stated in Figure 8 and Table 4 of the MC34903_4_5 datasheet. However, pin functions differ across variants (e.g., LIN pins are NC on MC34903P), so schematic and firmware must be validated for the specific variant - MC34903CS5EK maps to the MC34903S configuration with LIN support enabled.