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dc1941cfa
DEMO MANUAL DC1941C
Description
LTC6820
isoSPI 2-Wire Serial Interface
Demonstration circuit
board, based on Linear Technology’s
. The
LTC6820 provides a method of interconnecting standard
serial peripheral interface (SPI) devices using a single
twisted pair of wire up to 100 meters of distance, with
full galvanic isolation. This proprietary 2-wire interface is
called isoSPI and the LTC6820 encodes SPI signals, up to
1Mbps, into a differential isoSPI signal. The isoSPI signal
can then be transmitted across a simple pulse transformer
through a twisted pair, where an isoSPI receiver decodes
the transmission and recreates SPI signals.
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered and isoSPI and QuikEval
are trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
The SPI Bus is a synchronous serial data link that uses
four single-ended signals to transmit information over
short distances (typically on a single PCB). SPI devices
communicate in master/slave mode, where the master
device initiates the data frame and multiple slave devices
are allowed. Typically, the LTC6820 will be used in one of
two ways: See Figures 1 and 2.
Design files for this circuit board are available at
http://www.linear.com/demo
Figure 1. Connect an SPI Master Device to an SPI Slave Device
IP
120Ω
LTC6820
MSTR
MOSI
MISO
SCK
CS
IM
MASTER
µC
SDO
SDI
SCK
CS
IP
120Ω
LTC6820
MSTR
MOSI
MISO
SCK
CS
IM
REMOTE
SLAVE IC
SDI
SDO
SCK
CS
Figure 2. Connect an SPI Master (Typically a Microprocessor) to the Built-In isoSPI of an LTC6804
IP
120Ω
LTC6820
(MASTER)
MSTR
MOSI
MISO
SCK
CS
IM
MASTER
SDO
SDI
SCK
CS
120Ω
IPA
IMA
LTC6804
isoSPI PORT
