© 1999 Microchip Technology Inc.

Preliminary

DS21298B-page 15

MCP3204/3208

FIGURE 5-1:

Communication with the MCP3204 or MCP3208.

FIGURE 5-2:

Communication with MCP3204 or MCP3208 in LSB First Format.

CS

CLK

D

IN

D

OUT

D1

D2

D0

HI-Z

Don’t Care

Null

Bit

B11

B10

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

D2

SGL/

DIFF

Start

* After completing the data transfer, if further clocks are applied with CS low, the A/D Converter will output LSB

first data, then followed with zeros indefinitely. See Figure 5-2 below.

** t

a high impedance node, leaving the CLK running to clock out the LSB-first data or zeros.

t

t

SUCS

Null

Bit

B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11

CS

CLK

D

OUT

HI-Z

HI-Z

(MSB)

t

CONV

t

Power Down

t

SAMPLE

Start

SGL/

DIFF

D

IN

t

CYC

t

CSH

D0

D1

D2

* After completing the data transfer, if further clocks are applied with CS low, the A/D Converter will output zeros

indefinitely.

** t

high impedance node, leaving the CLK running to clock out LSB first data or zeroes.

t

SUCS

Don’t Care

*