Linear Technology DC1941C Demo Manual

Description

Demonstration circuit 1941
board, based on Linear Technology's
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.
Figure 2. Connect an SPI Master (Typically a Microprocessor) to the Built-In isoSPI of an LTC6804
is an isoSPI™ transceiver
LTC 6820. The
®
MASTER
µC
SDO
SDI
SCK
CS
REMOTE
SLAVE IC
SDI
SDO
SCK
CS
Figure 1. Connect an SPI Master Device to an SPI Slave Device
LTC6820
MASTER
(MASTER)
MSTR
IP
SDO MOSI
120
SDI MISO
SCK SCK
IM
CS
CS
DEMO MANUAL DC1941C
isoSPI 2-Wire Serial Interface
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
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.
LTC6820
MSTR
IP
MOSI
120
MISO
SCK
IM
CS
LTC6820
MSTR
IP
MOSI
120
MISO
IM
SCK
CS
LTC6820
LTC6804
isoSPI PORT
IPA
120
IMA
dc1941cfa
1