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Rainbow Electronics MAX1813 User Manual

Page 33

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MAX1813

Dynamically-Adjustable, Synchronous Step-Down

Controller with Integrated Voltage Positioning

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33

3.3V

100k

100k

100k

100k

100k

100k

VID4

VID3

VID2

VID1

VID0

1nF

GMUXSEL

SMBUS

ADDRESS

SMBUS

DATA

CLOCK

ADD0

ADD1

0

1

0

1

0

1

1

1

1

1

3.3k

ZMODE

CPU

MAX1813

3.3V

MAX1609

100k

100k

100k

100k

MAX1813

D4

D3

D2

D1

D0

ZMODE

*TO REDUCE QUIESCENT CURRENT, 1k

Ω PULLUP RESISTORS CAN BE REPLACED BY 1MΩ RESISTORS WITH 4.7nF CAPACATORS IN PARALLEL.

ZMODE HIGH

VID = 01010

→ 1.25V

CPU VID =
01100

→ 1.15V

(ZMODE LOW)

1k

1M

1k

1k

1k

1k

4.7nF

*OPTIONAL

3.15V TO 5.5V

100k

100k

CPU

ZMODE = HIGH = 1.25V
ZMODE = LOW = 1.15V

Figure 14. Using the Internal Mux with CPU Driving the Logic-Mode CID Code

Figure 15. Using the ZMODE Multiplexer