Analog Products Fact Sheet Networking MC33780 Dual DBUS Master with Differential Drive and Frequency Spreading DESCRIPTION Distributed Systems Interface 33780 SIMPLIFIED APPLICATION DIAGRAM The 33780 is a master device for two differential DBUS buses. It contains the logic to interface the buses to a standard serial peripheral interface (SPI) port and the analog circuitry to drive data and power over the bus as well as receive data from the remote slave devices. The differential mode of the 33780 generates lower electromagnetic interference (EMI) in situations where data rates and wiring make this a problem. Frequency spreading further reduces interference by spreading the energy across many channels, reducing the energy in any single channel. +5.0 V +25 V MCU 33780 VCC VCC SCLK CS SCLK MOSI MISO RST INT CLK MOSI MISO GND VSUP CS D0H D0L RST INT CLK Twisted Pair DBus Slave D1H D1L DBus Slave GND 4.7 nF capacitors from D0H, D0L, D1H and D1L to circuit ground are required for proper operation. APPLICATIONS • Sensor Bus for Automotive Airbag Systems • Simple 2-Wire Bus for Remote Control and Sensing • Automotive, Aircraft, Marine, and Industrial Control and Safety Systems • Heating, Ventilation, and Air-Conditioning (HVAC) PERFORMANCE Operating Range TYPICAL VALUES 9.0 – 25 V Data Rate 5 kB/s – 150 kB/s Bus Drive Current 200 mA/Channel Operating Temperature ESD (HBM) -40°C – 85°C ±2000 V QUESTIONS FEATURES • Are you working with vehicular safety or sensing systems? • Two independent DBUS I/Os • Common SPI interface for all operations • Do you need an inexpensive way to remotely power, measure, and control timing? • Open-drain interrupt output with pullup • Maskable interrupts for send and receive data status • Automatic message Cyclical Redundancy Checking (CRC) generation and checking • Four-stage transmit and receive buffers • Do you need a fault-tolerant control and sensing bus? • Would you like to use a remote sensor or control device without the need of a separate MCU and power supply at the remote site? • 8- to 16-bit messages with 0- to 8-bit CRC • 16-terminal SOIC wide body package • Independent frequency spreading for each channel • Additional devices available for comparison in Analog Product Selector Guide, SG1002 and Automotive Products Selector Guide, SG187 PROTECTION DETECT LIMITING SHUT DOWN Overcurrent/SC x x x Overtemperature x Overvoltage x x STATUS REPORTING x x CUSTOMER BENEFITS • Lower cost sensing and control system ORDERING INFORMATION Device • Bus carries both power and bi-direction communications Temperature Range (TA) Package -40°C to 85°C 16 SOICW • No critical clock components needed MC33780EG/R2 • Each part can handle up to 30 remote devices MCZ33780EG/R2 • Simple Serial Peripheral Interface (SPI) interface Data Sheet Order Number MC33780 • EMI is minimizing through the use of controlled voltage slew rates, differential signaling, and spread-spectrum signaling Contact Sales for Evaluation Kit Availability 16 SOICW 1.27 mm Pitch 10.3 mm x 7.5 mm Body Freescale™ and the Freescale logo are trademarks of Freescale Semiconductor, Inc. All other product or service names are the property of their respective owners. © Freescale Semiconductor, Inc. 2006. All rights reserved. MC33780FS Rev 3.0