Differential Receiver Drivers

JulianLights

Apprentice elf
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Jan 5, 2019
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Hi everyone
I have one of the old differential receivers (non-smart) and looking to replace the drivers as I believe I may have shorted one or both of them out.
I know absolutely nothing about drivers but one thing I noticed is that there appears to be two different types of drivers, the AM26LS32ACN and sn74ahct125n. Is this correct or can one be substituted for the other?
I’ve found these ones online but not entirely sure if they are the correct ones


 

TerryK

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Feb 9, 2020
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West Central Ohio
No, one cannot be substituted for the other. The AM device is a 16 Pin DIP (Dual Inline Package) while the SN device is only 14 pin. Other differences exist as well. The links are correct I think. Other vendors carry these I'm sure such as Mouser Electronics or Newark. Both ICs are manufactured by TI (Texas Instruments).
 

bpratt

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Mar 31, 2019
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Jimboomba, Queensland
wouldn't simply replacing your old receivers with new smart receivers be a lot easier, than trying to repair the older non-smart ones ?

I realise there's still a bit of 'fun' doing your own thing though. :)
 

darylc

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one of the chips is a driver, the other is a buffer from memory, different functions.
 

JulianLights

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Jan 5, 2019
Messages
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Thanks all, should have realised they were different with the different number of pins on each one!

And yes probably easier to just replace but like you said a bit of fun and thought at only a couple of dollars to replace the driver and buffer I thought I’d give it a try
 

TerryK

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West Central Ohio
one of the chips is a driver, the other is a buffer from memory, different functions.
There is not a significant difference between a driver and a buffer actually. While somewhat of a 'to-ma-to' 'to-mah-to' comparison, it would be more accurate to say all drivers are buffers but all buffers are not necessarily drivers. As I understand it, the (technical) connotation of 'driver' is a device of high or higher power capability while 'buffer' is more one of simple isolation between two entities or stages.

Thanks all, should have realised they were different with the different number of pins on each one!

And yes probably easier to just replace but like you said a bit of fun and thought at only a couple of dollars to replace the driver and buffer I thought I’d give it a try

TI calls the AM device a differential receiver and the SN device a buffer (but further in their documentation a driver). The AM26LS32 does not have much output capability as it is designed to move data to a logic bus whereas the SN74HCT125 does have a fair amount of output power. If the devices are socketed, the cost of obtaining replacement ICs is reasonable, and one is fairly sure the IC is defective I would suggest attempting a replacement. Just note the orientation (IC notch - Pin 1) when changing out the IC to insure the replacement IC orientation is the same.
 
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