Linear CCDs are an exceptionally cool component. They can be used for DIY spectrometers, and if you’re feeling very adventurous, a homemade version of those crappy handheld scanners of the early 90s. Linear CCDs don’t see much use around these parts, though, which makes [esben]’s Hackaday Prize entry very cool. He’s building a breakout to make using these linear CCDs easier.
A linear CCD module looks like an overgrown DIP chip with a glass window right on top of a few thousand pixels laid out in a straight line. The data from these pixels isn’t output as a series of ones and zeros, though: its old school, and the data this CCD produces is analog. This means reading light from one of these modules requires a fast microcontroller with a good ADC.
For this project, [esben] is using a Nucleo F401RE, a development board built around an STM32F4 microcontroller. This processor is fast enough to read the data off its 12 bit ADC, and store all three thousand pixels. Now the problem is getting this data off the microcontroller and onto some storage. With a UART limited to 230kB/s, each ‘frame’ of the CCD takes 300ms to transfer to a computer. [esben] really wishes that could be done a little faster, so he’s trying to hack the DMA controller to do his bidding. It looks like [esben] is on track to make a fast interface for a very common linear CCD, which means more cool tools and toys for all of us.
Even though I read the details I wonder weather the chip can stay analogue and be scanned at an audio rate and have a “film sound track” sample overlay. It would make a keyboard sampler that uses physical samples. I imagine that capacitance or something would limit it to fast scanning though.
You’re better off just replicating the regular photocell pickup that’s in projectors and mechanically scanning it at desired speed.
There could be a lot of flow-on benefit from making this $10 CCD more hacker friendly, great work!
True that. I have had one hanging around for ages that I had some idea of using in a spectrometer project, but didn’t know where to start with it.
awesome…i like it ..
From the project page “TCD1304 2-3$” were can you buy that CCD for that price?
Ali and eBay only give prices above 5 $/pcs.
There is a seller on ebay with free shipping at 3.50 USD now, they appeared in april and I don’t know if anyones tested them. Esben had some problems with dead sensors/reclaimed sensors depending on where he bought from. aquawayindustrial are around 7 USD each including shipping, but someone tested their batch and they were all good.
Thank you
This could be a really decent sensor for the Russian DIY lidar project that has been posted here some time ago:
http://hackaday.com/2016/06/05/in-soviet-russia-diy-laser-rangefinder-scan-you/
I’d like to see a breakout with a modern CCD, like the ELIS-1024, that is used in the Neato.
Fair comment but the ELIS-1024 isn’t actually a CCD and it’s only 1k pixels so it wouldn’t have the same level of performance. It’s odd they didn’t put an ADC on the chip. That’s not to say someone shouldn’t do a breakout board, but the TCD1304 doesn’t really have a replacement.
I owe Aitken and RW beers for answering excellently for me while I’ve been on vacation :)