LP3943ISQEV/NOPB National Semiconductor, LP3943ISQEV/NOPB Datasheet - Page 8

• Manufacturer Part Number: LP3943ISQEV/NOPB
• Description: BOARD EVAL FOR LP3943 FUNLIGHT
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LP3943ISQEV/NOPB

• Current - Output / Channel: 25mA
• Outputs And Type: 16, Non-Isolated
• Voltage - Output: 4 V
• Features: Dimmable
• Voltage - Input: 2.3 ~ 5.5 V
• Utilized Ic / Part: LP3943
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *LP3943ISQEV; *LP3943ISQEV/NOPB; LP3943ISQEV

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Application Notes
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
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
2
2
C master reads a register, the LP3943 will
C master reaches the last register (09H),
FIGURE 7. Programming with Auto Increment Disabled (in WRITE Mode)
FIGURE 8. Programming with Auto Increment Enabled (in WRITE Mode)
(Continued)
FIGURE 6. Register Address Byte
2
2
C
C
8
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.
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
20079613
20079612
2
C master does not