Thommen AD20 - Dial and Display Lighting Default Function; Fig. 2-2 Dial and Display Lighting; Table 2-3 Dial and Display; Lighting

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 25 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
2.3.1.5.1 Dial and Display Lighting Default Function
When external dial lighting is off or less than the threshold voltage VTH then the LCD light is at full
intensity. But when the external dial lighting voltage is more than the threshold voltage VTH it is
controlled externally. The lighting control is parametrical and set acc. to customer requirements.
100%
Lighting
Voltage
Lighting intensity
0
full
V
nom
OFF
V
TH
LCD backlighting curve
Dial lighting curve
Fig. 2-2 Dial and Display Lighting
Threshold Voltage(V
TH
)
acc. to customer requirements
Condition Display Lighting Intensity
Lighting 0 V / OFF full
Lighting < V
TH
full
Lighting >= V
TH
controlled
Table 2-3 Dial and Display Lighting