Hi,
I'm working on a 'race clock' which has mechanical 7 segment displays. Each segment driven by two solenoids one to set and another to clear the segment The solenoids are driven by UCN5801 NPN darlington arrays which I am unable to source. The clock uses one array to set and another to clear the segments. The arrays have parallel inputs and if I recall correctly the controller is a 6502. I don't have the time to reverse engineer the thing and control it with a more modern, more efficient microcontroller; this time around the repair is free as we replaced two of these drivers about one year ago (using the last two chips we had in the shop.) The company which produced the clock (Chronomix) no longer offers or makes this clock, so can offer no assistance.
Any ideas or insight welcome!
Thanks!
EDIT: I remember finding a surface mount part at one of the suppliers (could have been digikey) but it burnt up right away as it didn't have anywhere near the current handling of the DIP package. Just after that we found the box of parts a previous tech used to repair these clocks, and some of the drivers had been 'piggy backed' with one driver soldered over the next to double them up. Turned out most of the chips in the box were NFG, and only two were good. Those have both been used.
I'm working on a 'race clock' which has mechanical 7 segment displays. Each segment driven by two solenoids one to set and another to clear the segment The solenoids are driven by UCN5801 NPN darlington arrays which I am unable to source. The clock uses one array to set and another to clear the segments. The arrays have parallel inputs and if I recall correctly the controller is a 6502. I don't have the time to reverse engineer the thing and control it with a more modern, more efficient microcontroller; this time around the repair is free as we replaced two of these drivers about one year ago (using the last two chips we had in the shop.) The company which produced the clock (Chronomix) no longer offers or makes this clock, so can offer no assistance.
Any ideas or insight welcome!
Thanks!
EDIT: I remember finding a surface mount part at one of the suppliers (could have been digikey) but it burnt up right away as it didn't have anywhere near the current handling of the DIP package. Just after that we found the box of parts a previous tech used to repair these clocks, and some of the drivers had been 'piggy backed' with one driver soldered over the next to double them up. Turned out most of the chips in the box were NFG, and only two were good. Those have both been used.
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