Datasheet

MCP3002
DS21294E-page 16  2000-2011 Microchip Technology Inc.
FIGURE 5-1: Communication with the MCP3002 using MSB first format only.
FIGURE 5-2: Communication with MCP3002 using LSB first format.
CS
CLK
D
IN
D
OUT
MSBF
HI-Z
Null
Bit
B9 B8 B7 B6 B5 B4 B3 B2 B1 B0*
HI-Z
t
SAMPLE
t
CONV
SGL/
DIFF
Start
t
CYC
t
CSH
t
CYC
* After completing the data transfer, if further clocks are applied with CS low, the A/D Converter will output
zeros indefinitely. See Figure 5-2 for details on obtaining LSB first data.
** t
DATA
: during this time, the bias current and the comparator powers down while the reference input
becomes a high-impedance node.
t
DATA
**
t
SUCS
ODD/
SIGN
ODD/
SIGN
Don’t Care
Null
Bit
B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B1 B2 B3 B4 B5 B6 B7* B8 B9
CS
CLK
D
OUT
HI-Z
HI-Z
(MSB)
t
CONV
t
DATA
**
Power Down
t
SAMPLE
D
IN
t
CYC
t
CSH
* After completing the data transfer, if further clocks are applied with CS low, the A/D Converter will output zeros
indefinitely.
** t
DATA
: During this time, the bias circuit and the comparator powers down while the reference input becomes a
high-impedance node, leaving the CLK running to clock out LSB first data or zeroes.
t
SUCS
ODD/
SIGN
Start
SGL/
DIFF
MSBF
Don’t Care