Driving, Reliability, Maximum ratings – OSRAM ORBEOS Components User Manual
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4.1. Maximum ratings
Table 3: OLED maximum ratings.
3. Driving
In general, OLEDs are driven in constant current mode. If
dimming is required, it is recommended to use PWM (pulse
width modulation). Besides, it is also possible to adjust the
driving current. Please note that current modulation may in-
fl uence the color coordinates of the emitted light.
If several OLEDs are supposed to light up simultaneously, a
series connection has to be used. Parallel connection may
result in different luminance values or even cause damage of
the devices. OLEDs are designed for driving under forward
voltage only. Please avoid any kind of reverse voltage applied
to the OLED.
If a constant-current source design for LEDs is used, make
sure that the power supply doesn’t generate current and/or
voltage overshoots while switching it on or off.
4. Reliability
The core materials of an OLED device are organic semicon-
ductor compounds which currently cannot be used under
extreme conditions. OSRAM defi ned some generic maximum
ratings for the operation of ORBEOS
®
products as described
in table 3.
These ratings can also be found on the datasheets. Stresses
beyond the conditions listed in this table or the dedicated
datasheet may cause permanent damage to the device.
Stresses at maximum rating conditions for extended periods
may affect the device reliability. This may include optical arti-
facts and sudden failure modes such as shorts as well as
faster luminance degradation.
Parameter
Value
Relative humidity
40 °C/93 %
Operating temperature range
-20 … +40 °C
Storage temperature range
-40 … +60 °C
Operating and storage pressure
0.8 … 1.2 bar
DRIVING/RELIABILITY