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

DIN

DOUT

HI-Z

Null

Bit B9 B8 B7 B6 B5 B4 B3 B2 B1 B0*

HI-Z

tSAMPLE

tCONV

tCYC

tCSH

tCYC

* 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.

** tDATA: during this time, the bias current and the comparator powers down while the reference input

becomes a high-impedance node.

tDATA**

tSUCS

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

DOUT

HI-Z

HI-Z

(MSB)

tCONV

tDATA **

Power Down

tSAMPLE

DIN

tCYC

tCSH

* 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.

tSUCS

Don’t Care