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MBI1802
All-Ways-OnTM High-Power LED Driver
January 2005, V1.00
- 7 -
Application Information
Constant Current
In LED lighting applications, MBI1802 provides nearly no variations in current from channel to channel and from IC
to IC. This can be achieved by:
1) The maximum current variation between channels is less than ±3%, and that between ICs is less than ±6%.
2) In addition, the current characteristic of output stage is flat and users can refer to the figure as shown below. The
output current can be kept constant regardless of the variations of LED forward voltages (VF). This performs as
a perfection of load regulation.
MBI1802 IOUT vs. VOUT for various Rext
0
50
100
150
200
250
300
350
400
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
VOUT (V)
IOUT (mA)
Rext= 2907 ohm
Rext= 1455 ohm
Rext= 984 ohm
Rext= 732 ohm
Rext= 586 ohm
Rext= 491 ohm
Rext= 422 ohm
Figure 4