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MBI5026
16-bit Constant Current LED Sink Driver
April 2003, V0.8-4
- 15 -
The maximum power dissipation, PD(max) = (Tj – Ta) / Rth(j-a), decreases as the ambient
temperature increases.
Max. Power Dissipation at Various Ambient Temperature
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
-40
-30
-20
-10
0
10
20
30
40
50
60
70
80
90
Ambient Temperature
CNS Type: Rth = 82
CF Type: Rth = 96
CP Type: Rth = 112
Load Supply Voltage (VLED)
MBI5026 are designed to operate with VDS ranging from 0.4V to 1.0V considering the package
power dissipating limits. VDS may be higher enough to make PD(act) > PD(max) when VLED = 5V
and VDS = VLED – Vf, in which VLED is the load supply voltage. In this case, it is recommended to
use the lowest possible supply voltage or to set an external voltage reducer, VDROP.
A voltage reducer lets VDS = (VLED – Vf) – VDROP.
Resistors or Zener diode can be used in the applications as shown in the following figures.
VLED
VDROP
Vf
VDS
MBI5026
VLED
VDROP
Vf
VDS
MBI5026