Can I use a 27C040 eprom instead of 27C020?

N

Nick

Guest
I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????
 
Nick wrote:
I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????
Click to expand...
Haven't done this since the 2764 days, but you need to make sure you
don't have any floating address lines. If there's an extra address pin,
you can tie it high, low or to the next lowest address pin, depending on
which is easier in your circuit. Program it in the same configuration.
mike

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On Sat, 26 Mar 2005 01:05:12 -0800, mike <spamme0@netscape.net> wrote:

Nick wrote:
I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????



Haven't done this since the 2764 days, but you need to make sure you
don't have any floating address lines. If there's an extra address pin,
you can tie it high, low or to the next lowest address pin, depending on
which is easier in your circuit. Program it in the same configuration.
Click to expand...
Remember to duplicate the data over the two halves of the chip,
 
Mike Harrison wrote:
On Sat, 26 Mar 2005 01:05:12 -0800, mike <spamme0@netscape.net> wrote:


Nick wrote:

I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????



Haven't done this since the 2764 days, but you need to make sure you
don't have any floating address lines. If there's an extra address pin,
you can tie it high, low or to the next lowest address pin, depending on
which is easier in your circuit. Program it in the same configuration.


Remember to duplicate the data over the two halves of the chip,
Click to expand...
Why?
mike

--
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
..
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Wanted 13" LCD for Mitac 6133 Samsung HT13X13-201
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/
 
On Sat, 26 Mar 2005 05:37:21 -0800, mike <spamme0@netscape.net> put
finger to keyboard and composed:

Mike Harrison wrote:
On Sat, 26 Mar 2005 01:05:12 -0800, mike <spamme0@netscape.net> wrote:


Nick wrote:

I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????



Haven't done this since the 2764 days, but you need to make sure you
don't have any floating address lines. If there's an extra address pin,
you can tie it high, low or to the next lowest address pin, depending on
which is easier in your circuit. Program it in the same configuration.


Remember to duplicate the data over the two halves of the chip,


Why?
mike
Click to expand...
Because then it won't matter whether the extra address pin is
hardwired high or low in your circuit. The OP's job may be a repair of
an existing design, not necessarily a new design of his own.


- Franc Zabkar
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mike wrote:

Mike Harrison wrote:

On Sat, 26 Mar 2005 01:05:12 -0800, mike <spamme0@netscape.net> wrote:


Nick wrote:

I need to burn some data onto a 27C020 EPROM but can't get my hands
on one. Can I use a 27C040 instead????


Haven't done this since the 2764 days, but you need to make sure you
don't have any floating address lines. If there's an extra address pin,
you can tie it high, low or to the next lowest address pin, depending
on which is easier in your circuit. Program it in the same
configuration.



Remember to duplicate the data over the two halves of the chip,


Why?
mike

covers your butt incase you activate the extra address line.
Click to expand...
no change that way.
 
"Nick" <nickz@bigpond.net.au> wrote in message
news:aH11e.12020$C7.2839@news-server.bigpond.net.au...
I need to burn some data onto a 27C020 EPROM but can't get my hands on
one.
Can I use a 27C040 instead????
Click to expand...
I'm not familiar with that part, but with the 2764 we would burn the
data into the lower half and ground the pin for the most significant bit
so all that was accessible was the lower half. This assumes that the
pinouts for both chips are substantially the same.
 
Thanks for the help. I'll be able to erase the old eprom's now as I now have
access an eprom eraser. :)




"Nick" <nickz@bigpond.net.au> wrote in message
news:aH11e.12020$C7.2839@news-server.bigpond.net.au...
I need to burn some data onto a 27C020 EPROM but can't get my hands on one.
Can I use a 27C040 instead????
Click to expand...
 
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