The Electrical Engineering group has the difficult task of not just getting the electrical system to operate as intended but to do so over temperature ranges that can vary from -55C to +85C.
In addition, the building blocks of the electrical design are very configurable so that the resultant product seamlessly integrates into the higher level of assembly.
Electrical Design Elements
- Heater control for cold temperature operation.
- Can support multiple video interfaces such as RGB, DVI, LVDS, ARINC-818, and Display Port.
- Component stress analysis / de-rating
- FPGA & firmware
- Closed loop backlight controls (lifetime & temperature)
- Very detailed and customizable status reporting and BIT functionality
Closed Loop Backlight Control
Electrical engineers are experienced in making the system perform as intended over MIL-SPEC temperature ranges.
One example is shown below. In this case, a closed loop feedback algorithm is used to maintain backlight luminance and chrominance over temperature. It also contains a built-in self protect feature that reduces backlight power when the system is getting too hot.
Closed loop feedback control keeps backlight luminance constant over temperature until ‘self protect’ circuit kicks in when temperatures get too high. See drop in luminance.
Closed loop feedback control keeps rgb backlight chrominance constant over the same temperature test as shown on the left. Note changes in red, blue, and green led output over temperature as led efficacy changes. Also applies to aging effects for the LEDs.