MC3510 Datasheet, PDF (70/75 Pages) List of Unclassifed Manufacturers – Pilot Motion Processor

7.6 12-bit A/D Interface
The following schematic shows a typical interface circuit between the MC3510 and a quad 12 bit 2’s
complement A/D converter used as a position input device. Any single channel A/D can also be
used provided it meets the interface timing requirements.
Comments on Schematic
The A/D converter samples the 2’s complement digital words. DACRD- is used to perform the
read and is also used to load the counter to FFh. The counter will be reloaded for each read and will
not count significantly between reads. The counter will therefore start counting down after the last
read and will generate the cvt- pulse after 12.75 µsec. The conversions will take approximately 35
µsec, and the data will be available for the next set of reads after 50 µsec. The 12 bit words from the
A/D are extended to 16 bits with the 74LS244.
MC3510 Technical Specifications
70