KaVo ORTHOPANTOMOGAPH OP 2D, Service Manual

Page: 70 / 128

60 ORTHOPANTOMOGAPH OP 2D
3. Circuit Boards - CCD Sensor / Filter
CCD - Indicator lights
Remove the covers from the CCD side of the rotating
unit to see the indicator lights. On the rear of the CCD
sensor there are a number of LEDs that indicate the
status of the CCD sensor.
LED Colour Indicates
Power Yellow Indicates that the power signal is active.
Image Yellow Indicates image signal activity. Image signal led tells
the CCD sensor A/D-converter to sample image data
according to the TDI frequency.
TDI Clk Yellow Indicates that the clocking frequency of the CCD is
available.
Off TDI frequency is between 0...50Hz.
On TDI frequency is between 100 Hz...1kHz.
Flashing TDI frequency is between 50...100Hz or above 1kHz.
Power Supply LEDs Indicate the different voltages required by the CCD
sensor. The microcontroller in the CCD sensor monitors
the voltages and activates the LEDs accordingly.
There are software set limits for the various supply
voltages. The LEDs come on during image capture.
1 Yellow +3.3V and +1.8V LED
Supply voltages for the CCD clock controlling FPGA.
The +3.3V is generated by L1500.
The +1.8V step down is generated in CCD sensor
board from +3.3V.
LIMITS:
+3.3V between +3.0 and +3.6V.
+1.8V between +1.71V and +1.89V.
On when +3.3V and 1.8V are within limits.
2 Yellow Analog +5V LED.
Supply voltage for AD-converters.
LIMITS:
between +4.5V and +5.5V.
On when +5V is within limits.