MC33780FS, Dual DBUS Master with MC33780, Differential Drive and Frequency Spreading

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
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© Freescale Semiconductor, Inc. 2006. All rights reserved.
MC33780FS
Rev 3.0