Datasheet

MCP3909
DS22025C-page 30  2006-2012 Microchip Technology Inc.
FIGURE 5-7: Multiplier Output Mode 1 SPI Communication using 8-bit segments (Mode 0,1:
SCK idles low).
1234 5678 910111213141516
D19 D15 D14 D13 D12 D11 D10 D9 D8
MCU latches data from
Data is clocked out
on rising edges of SCK
Device on falling edges of SCK
Don’t Care
X XXXXXX
D15 D14 D13 D12 D11 D10 D9 D8D19 D18 D17 D16
XX
MCU Transmit Buffer
MCU Receive Buffer
X
Data is stored into the MCU
receive register after transmission
of the first 8 bits
Data is stored into the MCU
receive register after transmission
of the second 8 bits
D18 D17 D16
XXXXX
17 18 19 20 21 22 23 24
D2 D1 D0
XX
D3 D2 D1 D0
XX
MCU Transmit Buffer
MCU Receive Buffer
Data is stored into the MCU
receive register after transmission
of the third 8 bits
D3
XXX
D7 D6 D5 D4
Don’t Care
X = Don’t Care Bits
N = Null Bits
0000
D7 D6 D5
D4
F1 / SDI
F2 / SCK
NEG / SDO
F0 / CS
F0 / CS
F2 / SCK
F1 / SDI
NEG / SDO
X
X