CCDs?

[CTho9305]

How would you go about building an interface for a CCD? Just the CCD itself, no other boards. I haven't found a pinout yet (16 pins, DIP, no visible markings ), but assuming I do, where would I start?

 

[Mark R]

CCDs are quite straightforward - you apply a 'shutter' signal to activate it, and keep the signal asserted until the adequate exposure is achieved. Then you simply apply a clock signal to the output shift register, and on each clock pulse, the analogue voltage for the appropriate pixel is presented on the output.

Well, it's a bit more complex - there are usually seperate clock inputs for rows and columns, and for each subpixel. Don't forget to account for the dummy timing rows/columns, and the dark measurement rows/columns.

Some manufacturers have produced dedicated interface ICs for their higher end CCDs - All you do is connect an oscillator, and wait for the digital data to start pouring out. Another option is for a pulse controller IC - this controls the CCD, you just attach an ADC.

For a very low end CCD - you should be able to manage with a decent microcontroller. For anything with a decent number of pixels >320x200, you will really need a dedicated high-speed ADC otherwise you will be waiting all day for the image to be read out - then you've got to worry about where to put your data...

 

[CTho9305]

Cool, thanks So, what all goes into making a digital camera that is expensive? How much would it cost to buy the CCD?

 

[dkozloski]

If you want expensive, I saw a description of a remarkable imaging device for satellite photography that was a milliom pixels by a million pixels and measured 1/10 of an inch across. I'll bet that will flatten your wallet.

 

[Mday]

Originally posted by: CTho9305
Cool, thanks So, what all goes into making a digital camera that is expensive? How much would it cost to buy the CCD?

depends on the size.