FAN5607 Fairchild Semiconductor, FAN5607 Datasheet - Page 2

• Manufacturer Part Number: FAN5607
• Description: LED Driver with Adaptive Charge Pump DC/DC Converter
• Manufacturer: Fairchild Semiconductor

FAN5607
Definition of Terms
Output Current Accuracy: reflects the difference between the measured value of the output current (LED) and
programmed value of this current .
Current Matching: refers to the absolute value of difference in current between the two LED branches.
Efficiency: is expressed as a ratio between the electrical power into the LEDs and the total power consumed from the input
power supply.
Note:
1. Some competitors calculate the power efficiency as a function of V
2
due to the cathode
Efficiency
=
Current Matching (%)
i
--------------------------------------------
∑
=
4
1
Output Current Accuracy (%)
V
V
voltage 0
LEDi
IN
×
×
I
IN
I
LEDi
≠
and provides an efficiency “improved” up to 5%.
=
(
---------------------------------------------------------------------------------------------------- -
I
LED
(
I
LED
branch 1 I
=
branch 1
(
--------------------------------------------------------------------------------------------------------------------
I
OUT
–
measured I
LED
+
I
LED
branch 2
I
OUT
branch 2
OUT
–
programmed
OUT
instead of V
) 100
×
)
programmed
LED
. This method neglects the power lost
) 100
×
PRODUCT SPECIFICATION
REV. 1.0.0 6/22/04