NXP Semiconductors MCZ33990EF

Overview

MCZ33990EF from Freescale Semiconductor is an automotive-grade SAE J-1850 Class B serial transceiver in 8-pin SOICN (Pb-free EF suffix) package, operating from 9.0–16 V supply, supporting 10.4 kbps VPWM communication, with integrated waveshaping, thermal shutdown, and loss-of-ground protection - used as the physical layer interface between vehicle microcontrollers and single-wire Class B data buses.

For engineers reviewing the MCZ33990EF datasheet, MCZ33990EF pinout, MCZ33990EF application, or MCZ33990EF equivalent, this page delivers verified electrical specs, bus timing behavior, sleep-mode current draw (≤65 µA), BUS input hysteresis (0.1–0.6 V), and functional pin roles for automotive network diagnostics and ECU integration.

Technical Context

The MCZ33990EF implements a half-duplex, single-wire VPWM transceiver architecture with internal voltage regulator, bus waveshaping filter, and DMOS output driver. It supports true logic-level interfacing to 5.0 V CMOS microcontrollers while generating and decoding 0–7.0 V analog waveforms on the BUS line per SAE J-1850 Class B requirements.

Its functional modes - normal waveshaping (4X/LOOP = 0 V), 4X transmit (4X/LOOP = 5.0 V), and loopback (4X/LOOP = high-Z) - are controlled via a tristate input, and receiver operation remains active during SLEEP = 0 V, enabling wake-on-bus activity detection without transmitter enable.

Key Specifications

Pinout & Package

MCZ33990EF is housed in an 8-pin SOICN (Small Outline Integrated Circuit, Narrow) surface-mount plastic package, Pb-free per EF suffix designation, footprint compatible with JEDEC MS-012AC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SAE J-1850 Class B transceiver applications.

Compared with MCZ33990EF, MC33990D offers identical functionality without Pb-free compliance, while TJA1054 provides second-source availability with marginally relaxed sleep current and threshold specs - both require validation of BUS timing margins and thermal shutdown behavior in target vehicle harness environments.

Availability

MCZ33990EF is available at Aetrix Electronics and suitable for automotive diagnostics, body control modules, powertrain gateways, and chassis network nodes requiring stable component supply across extended temperature and voltage ranges.

Supply support for MCZ33990EF 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

Freescale Semiconductor (now part of NXP Semiconductors) is a fabless semiconductor company specializing in automotive, industrial, and networking ICs, with leadership in analog/mixed-signal and embedded controller technologies.

The MCZ33990EF belongs to Freescale's automotive analog transceiver product line, designed specifically to meet SAE J-1850 Class B physical layer requirements for legacy vehicle communication networks.

FAQ

What is the maximum bus load capacitance supported by the MCZ33990EF?

The MCZ33990EF supports Class B bus loads up to 16.55 nF (maximum) and 3.39 nF (minimum), calculated per SAE J-1850 specifications with up to 31 secondary nodes. This corresponds to total bus capacitance including primary node (3300 pF) and all secondary nodes (470 pF each), ensuring the RC time constant remains near 5.0 µs - a critical design constraint maintained by MCZ33990EF's internal waveshaping and driver characteristics.

Does the MCZ33990EF support automatic wake-up from sleep mode on bus activity?

No, the MCZ33990EF does not automatically wake up from sleep mode upon bus activity. When SLEEP = 0 V, the transmitter is disabled and VBAT current drops to ≤65 µA, but the receiver remains active and passes bus signals to RX. However, the microcontroller must assert SLEEP = 1 to re-enable transmission - MCZ33990EF itself does not generate a wake interrupt or toggle SLEEP autonomously.

What is the purpose of the LOAD pin on the MCZ33990EF?

The LOAD pin on the MCZ33990EF serves as a loss-of-ground protection mechanism. Under normal conditions, it acts as a saturated switch to ground, pulling down the external resistor between BUS and LOAD. During loss-of-ground, the internal transistor self-biases off, limiting LOAD pin leakage to ≤100 µA and preventing BUS corruption - a safety feature confirmed in MCZ33990EF's functional description and Figure 4 test circuit.

Can the MCZ33990EF operate with a 5.0 V supply instead of 12 V?

The MCZ33990EF requires minimum 9.0 V on VBAT for full operational bus dynamics, but bus transmission continues down to 5.0 V (with reduced output voltage tracking VBAT −1.6 V). Receiver operation remains functional down to 4.25 V. However, below 9.0 V, the internal regulator saturates and waveshaping degrades - so while MCZ33990EF may function at 5.0 V in RX-only mode, it does not meet SAE J-1850 Class B compliance at that voltage.

How does the 4X/LOOP pin affect BUS signal timing in the MCZ33990EF?

When 4X/LOOP = 5.0 V, the MCZ33990EF disables internal waveshaping, resulting in faster BUS edges: rise time <2.0 µs and fall time <5.0 µs (per external RC pull-down). In contrast, normal mode (4X/LOOP = 0 V) yields 9–15 µs rise/fall times. This 4X mode enables higher-speed proprietary protocols while retaining pin compatibility - a feature explicitly documented in MCZ33990EF's Functional Description section.