Document Number: MC33990
Rev 3.0, 11/2006
Enhanced Class B Serial
The 33990 is a serial transceiver designed to provide bi-directional
half-duplex communication meeting the automotive SAE Standard J-
1850 Class B Data Communication Network Interface specification. It
is designed to interface directly to on-board vehicle microcontrollers
and serves to transmit and receive data on a single-wire bus at data
rates of 10.4 kbps using Variable Pulse Width Modulation (VPWM).
The 33990 operates directly from a vehicle's 12 V battery system and
functions in a true logic fashion as an I/O interface between the
microcontroller's 5.0 V CMOS logic level swings and the required 0 V
to 7.0 V waveshaped signal swings of the bus. The bus output driver
is short circuit current limited.
• Designed for SAE J-1850 Class B Data Rates
• Full Operational Bus Dynamics Over a Supply Voltage of 9.0 V
to 16 V
• Ambient Operating Temperature of -40°C to 125°C
• Interfaces Directly to Standard 5.0 V CMOS Microcontroller
• BUS Pin Protected Against Shorts to Battery and Ground
• Thermal Shutdown with Hysteresis
• Voltage Waveshaping of Bus Output Driver
• Internally Reverse Battery Protected
• 40 V Max VBAT Capability
• Pb-Free Packaging Designated by Suffix Code EF
J-1850 SERIAL TRANSCEIVER
EF SUFFIX (PB-FREE)
-40°C to 125°C
Figure 1. 33990 Simplified Application Diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© Freescale Semiconductor, Inc., 2006. All rights reserved.