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SRAM+Flash hybrid FPGA contains an XC3S50A die from Xilinx and an Atmel DataFlash die wire-bonded together.
The die ID code of the FPGA (X8701) matches the regular XC3S50A.
Full-die imagery of the FPGA was not acquired because the die is identical to the regular XC3S50A, which has already been imaged.
Package
Label:
(X) XILINX (R) SPARTAN (R) XC3S50AN (TM) TQG144AGQ1341 D4631772A 4C
Device was decapped in-package with 68% HNO3 on 1/29/2014 by lab group A of CSCI 4974/6974 at RPI. Note leadframe damage and bond wires with one end floating; the floating bond wires were easily bent by a short blast of compressed air.
Flash die
FPGA die
The FPGA die is covered by an overcoat which can be scratched off with a scalpel blade but does not respond to acid. Possibly some sort of polyimide?
