Shift838 Posted March 25, 2020 Share Posted March 25, 2020 So i have found a supplier for some of the harder to find components that has some stock and willing to sell. If anyone want's to go in with me when i order a few I can get them added to the order. RTC-65271 (Epson - original clock chip used by Thierry in his design. has option for replaceable batteries!) $10.00 each 767143220G (CTS 7x22Ohm array 200mw) $1.50 each M68Z512W-70NC1 (original 512k SRAM used in card) $5.50 each these are all the original and they come from one distributor. If anyone want's in let me know via PM and we can work out a paypal. 4 Quote Link to comment Share on other sites More sharing options...
+FarmerPotato Posted March 26, 2020 Share Posted March 26, 2020 Is that a 220 ohm array? I’m looking at Mouser now. Does it match pinout with a new one? https://www.mouser.com/ProductDetail/Bourns/4608X-101-221LF?qs=%2Fha2pyFadujGrwpxGSma51gvPokZCwAar6UktZ%2FCb%2Fnq5CFgv9kryg%3D%3D I was in need of the 220-330 ohm dual terminator. They’re very cheap new. Quote Link to comment Share on other sites More sharing options...
Shift838 Posted March 26, 2020 Author Share Posted March 26, 2020 3 minutes ago, FarmerPotato said: Is that a 220 ohm array? I’m looking at Mouser now. Does it match pinout with a new one? https://www.mouser.com/ProductDetail/Bourns/4608X-101-221LF?qs=%2Fha2pyFadujGrwpxGSma51gvPokZCwAar6UktZ%2FCb%2Fnq5CFgv9kryg%3D%3D I was in need of the 220-330 ohm dual terminator. They’re very cheap new. no the one for the ide card is a SOIC14 package Isolated and needs to be .2 w or higher. Quote Link to comment Share on other sites More sharing options...
+FarmerPotato Posted March 26, 2020 Share Posted March 26, 2020 1 hour ago, Shift838 said: no the one for the ide card is a SOIC14 package Isolated and needs to be .2 w or higher. Righto. The Bourns equivalent for $0.60 is in SOM14 . But its leads extend out to 7.62 mm while the SOIC14 leads extend out to 6 mm. https://www.mouser.com/datasheet/2/54/4800P-777115.pdf It might not fit on the pad. I guess you have the best price on the original chip. Quote Link to comment Share on other sites More sharing options...
Shift838 Posted March 26, 2020 Author Share Posted March 26, 2020 13 hours ago, FarmerPotato said: Righto. The Bourns equivalent for $0.60 is in SOM14 . But its leads extend out to 7.62 mm while the SOIC14 leads extend out to 6 mm. https://www.mouser.com/datasheet/2/54/4800P-777115.pdf It might not fit on the pad. I guess you have the best price on the original chip. I looked at these Bourns too and came to the same conclusion on the leads. Quote Link to comment Share on other sites More sharing options...
F.G. Kaal Posted March 26, 2020 Share Posted March 26, 2020 Depends on what you want to do with the IDE card and this clock chip... but a quick look at the datasheet told me that this clock chip has 128 pages of 32 bytes, that is a total of 4096 bytes. I also don't see a pin that can supply a (backup) voltage to the RAM chip like the other clock chips do Thierry used/mentioned. IMHO this is not the correct clock chip to go for. BTW: The size of my DSR for the IDE card is about 8Kb +9*4Kb = 44Kb Fred 3 Quote Link to comment Share on other sites More sharing options...
F.G. Kaal Posted March 26, 2020 Share Posted March 26, 2020 (edited) If I'm correct with my previous statement: Brain wave alert: You can also create a little board with an extra 3V battery (and the transistors\resistors\diodes as I did for the HDX project) and use this as backup for the RAM chip and place it at one of the other clockchip locations. Fred Edited March 26, 2020 by F.G. Kaal 2 Quote Link to comment Share on other sites More sharing options...
Shift838 Posted March 26, 2020 Author Share Posted March 26, 2020 36 minutes ago, F.G. Kaal said: If I'm correct with my previous statement: Brain wave alert: You can also create a little board with an extra 3V battery (and the transistors\resistors\diodes as I did for the HDX project) and use this as backup for the RAM chip and place it at one of the other clockchip locations. Fred interesting. I did not even think about that one! will be putting more feelers out then to see if I can locate a BQ4847YMT the original one we all used for the original buy. although these batteries in this unit cannot be replaced, with a little dremel work and a 3v battery holder a new battery can be wired up once the battery dies. Quote Link to comment Share on other sites More sharing options...
Shift838 Posted March 27, 2020 Author Share Posted March 27, 2020 I have found the original BQ4847YMT real time clock chip. The supplier has quite a bit and are willing to sell them at $8.00 each + shipping 3 Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted March 27, 2020 Share Posted March 27, 2020 The chip on the top, in the socket, is my (defective) original one, the one in the red foam was a helpless try to replace it... Quote Link to comment Share on other sites More sharing options...
GDMike Posted March 28, 2020 Share Posted March 28, 2020 (edited) I've got three of these 58167 RTC chips.. I've always wondered if I could interface one with the TI.. eneral Description The MM58167B is a low threshold metal gate CMOS circuit that functions as a real time clock in bus oriented microproc- essor systems. The device includes an addressable real time counter, 56 bits of RAM, and two interrupt outputs. A POWER DOWN input allows the chip to be disabled from the rest of the system for standby low power operation. The time base is a 32.768 kHz crystal oscillator. Features Y Microprocessor compatible (8-bit data bus) Y Milliseconds through month counters Y 56 bits of RAM with comparator to compare the real time counter to the RAM data Y 2 INTERRUPT OUTPUTS with 8 possible interrupt signals Y POWER DOWN input that disables all inputs and out- puts except for one of the interrupts Y Status bit to indicate rollover during a read Y 32.768 kHz crystal oscillator Y Four-year calendar (no leap year) Y 24-hour clock Edited March 28, 2020 by GDMike Quote Link to comment Share on other sites More sharing options...
Swim Posted March 28, 2020 Share Posted March 28, 2020 My favorite solution for the IDE has always been the bq4852YMC-85 like the one listed here. The TI has gone obsolete but the Rochester one is still available. https://www.digikey.com/product-detail/en/rochester-electronics-llc/BQ4852YMC-85/2156-BQ4852YMC-85-TI-ND/11538020 2 1 Quote Link to comment Share on other sites More sharing options...
Shift838 Posted April 5, 2020 Author Share Posted April 5, 2020 (edited) I think i may have found a suitable replacement for the clock chip. It will require me to make a adapter for it. TI tells me it should work in theory and all I have to do is add a crystal and 3v battery to it and of course the external SRAM since it has the ability to control SRAM. It has the same pinout as the BQ4847YMT. I may give this a shot one of my boards to test. The clock chip is of course made by TI, it's the BQ4802YDW and is 5v. Edited April 5, 2020 by Shift838 6 Quote Link to comment Share on other sites More sharing options...
GDMike Posted April 5, 2020 Share Posted April 5, 2020 Ooohhh... this is coool...how to add it to a supercart Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.