LP3944_14 Datasheet, PDF (9/17 Pages) Texas Instruments – RGB/White/Blue 8-LED Fun Light Driver

www.ti.com
LP3944
SNVS264 – MAY 2004
Figure 9. Register Address Byte
In the READ mode, when auto increment is enabled, I²C master could receive any number of bytes from LP3944
without selecting chip address and register address again. Every time the I²C master reads a register, the
LP3944 will increment the register address and the next data register will be read. When I²C master reaches the
last register (09H 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
I²C master writes to register. When the last register (09H register) 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 functional. 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 I²C master does not change register address, it will continue to write data
into the same register.
Figure 10. Programming with Auto Increment Disabled (in WRITE Mode)
Figure 11. Programming with Auto Increment Enabled (in WRITE Mode)
Address (Hex)
0x00
0x01
0x02
0x03
0x04
0x05
0x06
0x07
Table 1. LP3944 Register Table
Register Name
Input 1
Register 1
PSC0
PWM0
PSC1
PWM1
LS0
LS1
Read/Write
Read Only
Read Only
R/W
R/W
R/W
R/W
R/W
R/W
Register Function
LED0–7 Input Register
None
Frequency Prescaler 0
PWM Register 0
Frequency Prescaler 1
PWM Register 1
LED0–3 Selector
LED4–7 Selector
Copyright © 2004, Texas Instruments Incorporated
Product Folder Links: LP3944
Submit Documentation Feedback
9