Lighting board:
Device classification
Boost regulator for lighting application
Operating Voltage / Current
5V / 250mA
Digital/Analog
Analog circuitry
Switching Frequency
~500KHz
LED drive Voltage / Current
~25V / 20mA (Drives a string of IR, UV, White LEDs)
Intentional Radiation
No
Software requirements
None. Starts up as soon as power is applied
Operational Description:
The lighting board drives a set of IR, UV and white LEDs. The circuit is controlled by the imager circuit
through I2C interface. The choice of IR/UV/White illumination is done by the host application and is
handed down to the lighting board through the I2C interface. The lighting board has a step up DC-DC
converter and current controlled LED drivers to accomplish the intended purpose.
Sounder:
Device classification
Audible tone generator
Operating Voltage / Current
3.3V / 20mA
Digital/Analog
Digital circuitry
Operating Frequency
8 MHz
Intentional Radiation
No
Software requirements
None. Camera imager digital circuit controls the tone generator. The
communication is through SPI interface operating at 100KHz.
Operational Description:
Sounder block is basically a small microcontroller that generates tones. The sounder controller receives
commands from the camera digital circuit on which tone it has to play. With this kind of arrangement,
the USB host software can access the sounder through the camera digital circuit.
