KIT33811EGEVBE Evaluation Board
, Rev. 2.0
Freescale Semiconductor
8
Circuit Description and Operation
6
Circuit Description and Operation
The 33811 EVB provides the user with a means to evaluate the operation of the 33811
Solenoid Monitor Circuit. The 33810 Injector/Ignition Driver circuit provides the solenoid
drivers that serve as the host for the 33811 circuit. The inputs to the 33810 circuit are
jumpered via JP1 to the 16 pin I/O connector. If the user wishes to provide the 5 input
signals externally, then the jumpers in JP1 can be removed and the input signals can
be connected to pins 1,3,5,7, and 9 of JP1. Please see the schematic diagram for
further details. If the user wishes to use the USB/SPI Dongle and SPIGen program to
provide the inputs to the 33811 EVB inputs, then Jumpers 1 - 5, on JP1, should be left
connected. The OUTPUTs 1 - 5 can be connected to external solenoids. The solenoids’
second connection is to VPWR. Three outputs (OUT 1, 2, and 3) are provided by the
33810 injector drivers directly. For information on these outputs, please refer to the
33810 Data Sheet, included on the accompanying CD. The remaining two outputs,
(OUT 4, 5) are provided by a dual MOSFET, IR7341, which are driven by the 33810
GPGD circuits. For information of these outputs please refer to IR’s web site:
http://www.irf.com/
for the data sheet on this device and the data sheet for 33810.
The SPI port, SO, SI SCLK and CS are shared between the 33810 and 33811 circuit.
The means for sharing the SPI port is by multiplexing the CS line, using CNTL0 and
CNTL1. When CNTL0 is low (logic 0) and CNTL1 is high (logic 1) CS is routed to the
33810 circuit. When CNTL0 high (logic 1) and CNTL1 is low (logic 0), CS is routed to
the 33811 circuit. The conditions with both CNTL0 and CNTL1 high or both low should
not be allowed to occur. See the truth table below for more information:
The remaining CNTL lines, CNTL2 and CNTL3 are used to control the 33811 RESET
line and 33810 OUTPUT_ENABLE line, respectively. For information about the
operation of the RESET and OUTPUT_ENABLE lines, please refer to the 33811 and
33810 data sheets, included on the accompanying CD.
Truth Table for CNTL0 and CNTL1
CNTL0
CNTL1
SPI Port Connection
Comments
0
0
Invalid
SPI drives both 33810 and 33811 SO conflict
0
1
33810
1
0
33811
1
1
Invalid
SPI not connected to either 33810 or 33811