AUTO INCREMENT

Auto increment is a special feature supported by the LP3943

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”.

Bits 5, 6 and 7 in the register address byte should always be

zero.

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

master could receive any number of bytes from LP3943

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

the register address will roll over to 00H.

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

LP3943 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, not

00H, because the first two registers in LP3943 are read-only

registers. It is possible to write to the first two registers

independently, and the LP3943 will acknowledge, but the

data will be ignored.

If auto increment is disabled, and the I

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

same register.

20079611

FIGURE 6. Register Address Byte

20079612

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

20079613

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

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