Document Number: MC33780 Freescale Semiconductor Rev 4.0, 11/2006 Advance Information Dual DBUS Master with 33780 Differential Drive and Frequency Spreading The 33780 is a master device for two differential DBUS buses. It contains the logic to interface the buses to a standard serial DIFFERENTIAL DBUS MASTER 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 electro- magnetic interference (EMI) in situations where data rates and wiring make this a problem. Frequency spreading further reduces in- terference by spreading the energy across many channels, reducing the energy in any single channel. Features Two Independent DBUS I /Os EG (PB-FREE SUFFIX) Common SPI Interface for All Operations 98ASB42567B Open-Drain Interrupt Output with Pull-up 16-PIN SOICW Maskable Interrupts for Send and Receive Data Status Automatic Message Cyclical Redundancy Checking (CRC) Generation and Checking Four-Stage Transmit and Receive Buffers ORDERING INFORMATION 8- to 16-Bit Messages with 0- to 8-Bit CRC Temperature Independent Frequency Spreading for Each Channel Device Package Range (T ) A Pb-Free Packaging Designated by Suffix Code EG MC33780EG/R2 -40C to 85C 16 SOICW MCZ33780EG/R2 +5.0 V +25 V MCU 33780 VCC VCC VSUP DSI/DBUS SLAVE SCLK SCLK 33793 Twisted Pair CS CS D0H MOSI MOSI D0L MISO MISO RST DSI/DBUS SLAVE RST D1H 33793 INT INT D1L CLK CLK 4.7 nF capacitors from D0H, D0L, D1H GND GND and D1L to circuit ground are required for proper operation. Figure 1. 33780 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.INTERNAL BLOCK DIAGRAM INTERNAL BLOCK DIAGRAM VCC VSUP CLK DSIF DSIS D0H DBUS Driver/Receiver D0L DSIR Spreader DSIF DSIS D1H DBUS Driver/Receiver D1L DSIR SCLK MISO SPI, Registers and MOSI Interrupt T CS LIM Generator INT GND RST GND GND Figure 2. 33780 Internal Block Diagram 33780 Analog Integrated Circuit Device Data 2 Freescale Semiconductor Protocol Engine