Prototypes & Products: FCD4A14 / AT77C101A / AT77C102A

In 1999, we designed the FCD4A14, a new smaller device with an integrated analog to digital converter. It is possible to directly connect the device to the parallel port of a PC, but also to any microprocessor parallel bus. It is the first to reach high volume production.

Called FCD4A14 under the Thomson-CSF era, it was renamed AT77C101A when becoming Atmel in 2000.

The AT77C102A is a clone version officialy disclosed in February 2006 using a new process which enabled to enhance the sensitivity, and also because the old process was becoming obsolete.

The FCD4A14 / AT77C101A is a 8x280 pixels 500dpi chip, with an integrated analog to digital converter. The chip is much smaller than the previous FC15A140 (30x280 pixels) and much more practical as it required no additional circuitry to be used.

The AT77C102A is a clone in another CMOS process: same size and shape. The main difference was the smaller maximum voltage: it was a 3.3 volt chip, the C101 was a 5 volt chip.

FCD4A14 / AT77C101A

AT77C101 bare chip

The same DIL ceramic package than the FC15A140 was used to start the production.

A low cost COB (Chip-On-Board) version quickly entered in production, pushed by the HP iPAQ that was starting. Grey color was chosen as the most neutral one.

But it was possible to create any color we wanted.

AT77C101 colored versions

A COB version with a connector for flex was also available.

A smaller COB version has also been released, and it was possible to directly solder the flexible connection.

Some other packages have been tried, for instance this Chip-On-Flex version.

AT77C101 on flex

Preparing the future versions, a molded version with a very small footprint was successfully tested.

The AT77C102A (the "C102") was a clone version, released with the same original COB package.

First prototype in 2003, production in 2006.


FCSWEEP02 demo kit used the same external package than the first Sweepee, but used the new chip AT77C101, keeping the USB interface chip from SCM.
Released at the CTST '00 / Miami on the Atmel booth.


FCSWEEP03 also called the Sweepee Genesys, got the same circuitry than FCDEMO4 (below), but taking advantage of the Sweepee package and using the DIL version.
It was released in 2001.



These were demonstration kits for the AT77C101, COB package to show how to make a low cost reader. Two versions existed:

  • FCDEMO4 is the USB version, using the Genesys USB interface chip.
  • FCDEMO5 is the parallel port version, directly connected to an EPP (enhanced parallel port) existing on most PCs, without driver up to Win98.

    The AT77C101 has been used in many third-party projects.

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