6815854H01-A June 15, 2005
Product Overview: Control-Head Assembly 2-3
2.3.3.2 Keypad, Volume and Frequency Knob
The control head assembly processes all menu button inputs and visual indicators through the
application processor. The buttons are programmable to allow different modes of operation through
the CPS. All buttons are backlit to allow operation in low light.
The volume knob allows a linear step of the volume and integrates the on/off function.
2.3.3.3 Status LEDs
Three LEDs (Green, Yellow, Red) are driven by the applications processor through the toggling of
three transistors. The biasing voltage level is 2.8Vdc while the LEDs are driven by SW_B+ at 13.8V.
2.3.3.4 Backlight LEDs
The applications processor operates the backlight LEDs via two transistors controlling all the
backlight LEDs, providing two different brightness levels by way of toggling the base of the
transistors. The biasing voltage level is also 2.8Vdc while the LEDs are driven by SW_B+ at 13.8V.
The dim feature can be activated via CPS.
To Next Page
Loading...
