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SPI
Intel® Quark™ SE Microcontroller C1000
June 2017
Platform Design Guide
Document Number: 334715-004EN
35
SPI Single Flash
MOSI/MISO/SPI_IO/CLK/CS
SoC Breakout
Main Routing
Device Breakout
Routing Layer
(Microstrip/Stripline/Dual
Stripline)
MS/SL
MS/SL
MS/SL
Characteristic Impedance
50Ω +/- 10%
50Ω +/- 10%
50Ω +/- 10%
Trace Width (w)
3.5 mils minimum
Meet
impedance
Meet impedance
Trace Spacing (S1): Between
SPI signals
4 mils
3W
2W
Trace Spacing (S2): Between
SPI signals and other signals
5 mils
3W
2W
Trace Spacing(S3): Between
SPI_CLK to other signals
5 mils
3W
2W
Trace Length
<100 mils
1500 mils <
TL0+TL1+TL2
< 10000 mils
<500 mils
Length mismatch between
SPI_CLK and SPI_CS
<250 mils
Length mismatch between
SPI_CLK and DATA
(SPI_IO/MOSI/MISO)
<250 mils
Trace Total Length
1500 mils < Total Length < 10000 mils
Number of vias allowed
4
Via stub length
< 80 mils
Rs
33Ω
Reference
VSS referencing
W
W is the trace width
Figure 16. SPI Point-to-Point Dual Flash Topology
TL0
TL1
TL3
FLASH
Device 0
Dual Load
MOSI/MISO/SPI_IO/CLK
ATP SOC
Rs
TL3
FLASH
Device 1
Rs
TL2
TL2