Just had my first keyboard fail on me overnight while asleep. Acting as if all keys were pressing randomly, the three X-Lock led's blinking all at rapid intervals, etc. It is connected over a PS/2 to USB converter and has been working fine for well over a year till now. Find out the Chip-on-board with epoxy on the keyboards key matrix controller. It let out the magic smoke leaving the burnt smell and a nice brownish discolouration off-centre from the top of the black epoxy. Tested with another keyboard on spare and the converter it is working fine.
The converter used is the one most commonly recommended for even the old IBM Model-M keyboards. Not shown in the images on the page is the fact it is covered by a sticker is that it uses a Cypress CY7C63723C/SXC IC.
Link @ http://www.clickykeyboards.com/index...id/0/id/124184
Keyboard used was Compaq Model-5107 due to key layout:
The questions are:
1) How often is the expected lifespan of the key matrix controller?
2) What could have caused it? Unclean power from the USB filtered with the converters' 10uf cap overtime? If a possibility... would changing the cap be of any benefit as the screening on the board indicates a larger cap that what is in place?
3) Do key matrix controller IC's overheat at all and if so what could cause that to happen?
The converter used is the one most commonly recommended for even the old IBM Model-M keyboards. Not shown in the images on the page is the fact it is covered by a sticker is that it uses a Cypress CY7C63723C/SXC IC.
Link @ http://www.clickykeyboards.com/index...id/0/id/124184
Keyboard used was Compaq Model-5107 due to key layout:
The questions are:
1) How often is the expected lifespan of the key matrix controller?
2) What could have caused it? Unclean power from the USB filtered with the converters' 10uf cap overtime? If a possibility... would changing the cap be of any benefit as the screening on the board indicates a larger cap that what is in place?
3) Do key matrix controller IC's overheat at all and if so what could cause that to happen?
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