ncp5890 ON Semiconductor, ncp5890 Datasheet - Page 15

• Manufacturer Part Number: ncp5890
• Description: Light Management Ic Dedicated For Lcd Backlighting And Multi-led Fun Light Applications
• Manufacturer: ON Semiconductor

NCP5890
ILED Max
(25 mA, programmable)
Ambient Light
Gradual Dimming:
I−setup
Photo sense
de−activated
ILED Min (Programmable)
Photo Sense
The photo sense register is loaded with the I2C content
Ambient Light < I2C ILED : the Photo sense controls the ILED
The Photo Sense cannot force t he ILED below the pre−programmed minimum level
The Photo Sense controls ILED within the Imin and I−setup limits
When a Downward Gradual Dimming is engaged, the ILED is reduced from the level
defined by the Photo sense to the lower value defined by the gradual dimming register containt.
Figure 14. Basic Gradual Dimming and Photo Sense Operation Strategy
Figure 15. Basic Ambient Photo Sense Regulation (PSPICE simulation)
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