and Lookup Table

____________________________________________________________________

13

Reading multiple bytes from a slave: The read opera-

tion can be used to read multiple bytes with a single

transfer. When reading bytes from the slave, the master

simply ACKs the data byte if it desires to read another

byte before terminating the transaction. After the master

reads the last byte it must NACK to indicate the end of

the transfer and generates a STOP condition.

Applications Information

Power-Supply Decoupling

To achieve the best results when using the DS3501,

decouple both the power-supply pin and the wiper-bias

voltage pin with a 0.01µF or 0.1µF capacitor. Use a

high-quality ceramic surface-mount capacitor if possi-

ble. Surface-mount components minimize lead induc-

tance, which improves performance, and ceramic

capacitors tend to have adequate high-frequency

response for decoupling applications.

SDA and SCL Pullup Resistors

SDA is an I/O with an open-collector output that

requires a pullup resistor to realize high-logic levels. A

master using either an open-collector output with a

pullup resistor or a push-pull output driver can be used

for SCL. Pullup resistor values should be chosen to

ensure that the rise and fall times listed in the

Electrical Characteristics are within specification. A typ-

ical value for the pullup resistors is 4.7k

Ω.

Chip Information

TRANSISTOR COUNT: 22,400

SUBSTRATE CONNECTED TO GROUND

SLAVE

ADDRESS*

START

START

0

1

0

1

0

A1

A0

R/W

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

MSB

LSB

MSB

LSB

MSB

LSB

b7

b6

b5

b4

b3

b2

b1

b0

READ/

WRITE

REGISTER ADDRESS

b7

b6

b5

b4

b3

b2

b1

b0

DATA

STOP

SINGLE-BYTE WRITE

-WRITE LUTAR

REGISTER TO 00h

SINGLE-BYTE WRITE

SET TO LUT MODE

SINGLE-BYTE READ

-READ CR0 REGISTER

TWO-BYTE WRITE

- WRITE 80h AND 81h TO 00h

START

REPEATED

START

51h

MASTER

NACK

STOP

0 1010000

00000 010

02h

01010 001

0 1010000

00001 000

50h

08h

STOP

START 0 1010000

00000 011

50h

CR1 (03h)

STOP

DATA

01h

*THE SLAVE ADDRESS IS DETERMINED BY ADDRESS PINS A0 AND A1.

00 000 000

0 00 0 0 0 0 1

50h

A)

C)

B)

D)

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

START 0 1010000

10000 000

50h

80h

STOP

00h

0 00 0 0 0 0 0

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

00h

0 00 0 0 0 0 0

SLAVE

ACK

TWO-BYTE READ

- READ 80h AND 81H

E)

START 0 1010000

10000 000

50h

80h

STOP

SLAVE

ACK

SLAVE

ACK

SLAVE

ACK

MASTER

ACK

51h

0 10 1 0 0 0 1

DATA

DATA

MASTER

ACK

LUT 1

LUT 0

REPEATED

START