AUTO INCREMENT

Auto increment is a special feature supported by the LP3944

to eliminate repeated chip and register addressing when

data are to be written to or read from registers in sequential

order. The auto increment bit is inside the register address

byte, as shown in Figure 6. Auto increment is enabled when

this bit is programmed to “1” and disabled when it is pro-

grammed to “0”.

In the READ mode, when auto increment is enabled, I

master could receive any number of bytes from LP3944

without selecting chip address and register address again.

Every time the I

increment the register address and the next data register will

be read. When I

register), the register address will roll over to 00H.

In the WRITE mode, when auto increment is enabled, the

LP3944 will increment the register address every time I

master writes to register. When the last register (09H regis-

ter) is reached, the register address will roll over to 02H,

because the first two registers in LP3944 are read-only

registers. It is possible to write to these two registers, and the

LP3944 will acknowledge, but the data will be ignored.

In the LP3944, registers 0x01, 0x08 and 0x09 are not func-

tional. However, it is still necessary to read from 0x01 and to

write to 0x08 and 0x09 in Auto Increment mode. They cannot

be skipped.

If auto increment is disabled, and the I

change register address, it will continue to write data into the

same register.

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FIGURE 6. Register Address Byte

20085312

FIGURE 7. Programming with Auto Increment Disabled (in WRITE Mode)

20085313

FIGURE 8. Programming with Auto Increment Enabled (in WRITE Mode)

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