TABLE 3. LP3947 Serial Port Communication address code 7h’47

LP3947 Control and Data Codes

Addrs

Register

7

6

5

4

3210

8'h00

Charger

Register -1

Batt Voltage

(0) = 4.1V

1 = 4.2V

AC Adaptor

Charge

Current

Code 3

(1)

AC Adaptor

Charge

Current

Code 2

(0)

AC Adaptor

Charge

Current

Code 1

(0)

AC Adaptor

Charge

Current

Code 0

(0)

8'h01

Charger

Register -2

EOC

(Green LED)

R/O

Charging

(Red LED)

R/O

EOC

SEL-1

(0)

EOC

SEL-0

(1)

8'h02

Charger

Register -3

USB

Charge

Current

Code 3

(1)

USB

Charge

Current

Code 2

(0)

USB

Charge

Current

Code 1

(0)

USB

Charge

Current

Code 0

(0)

Numbers in parentheses indicate default setting. “0” bit is set to low state, and “1” bit is set to high state. R/O –Read Only, All other bits are Read and Write.

TABLE 4. Charger Current and EOC Current Programming Code

Data Code

Charger Current

Selection Code I

End of Charge Current

Selection Code

4h'00

100

4h'01

150

0.1C

4h'02

200

0.15C

4h'03

250

0.2C

4h'04

300

4h'05

350

4h'06

400

4h'07

450

4h'08

500

4h'09

550

4h'0A

600

4h'0B

650

4h'0C

700

4h'0D

750

20111012

w = write (sda = “0”)

r = read (sda = “1”)

ack = acknowledge (sda pulled low by either master or slave)

Nack = No Acknowledge

rs = repeated start

FIGURE 7. LP3947 (Slave) Register Write

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