Technical Reference Note
Trim Characteristics
Rev.07.04.14_#1.0
AVO100-36S3V3B-6L
Page 19
Connecting an external resistor between Trim pin and Vo- pin will decrease the output voltage. While connecting it
between Trim and Vo+ will increase the output voltage. The following equations determine the external resistance to obtain
the trimmed output voltage.
510
Radj−down
=
−10.2(KΩ)
∆
5.1×Vnom
×
100+ ∆
510
Radj−up
=
−
−10.2(KΩ)
1.225× ∆
∆
△:Output e rate against nominal output voltage.
100× (Vnom −V0 )
∆ =
Vnom
Vnom: Nominal output voltage.
For example, to get 3.63V output, the trimmingresistor is
100×(Vnom −V0 ) 100×(3.63− 3.3)
=
∆ =
=10
Vnom
3.3
5.1×3.3×
100 +10
510
Radj−up
=
−
−10.2 = 89.9(KΩ)
1.225×10
10
The output voltage can also be trimmed by potential applied at the Trim pin.
VO = (Vtrim +1.225)×1.347
V
is the desired output voltage.
o
V
Where
is the potential applied at the Trim pin, and
trim
When trimmingup, the output current should be decreased accordingly so as not to exceed the maximum output power.
Figure 21 Trim up
Figure 22 Trim down
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