Non-S.O.I.C. Serial Flash?

[kingsteven]

Hi,

I want to add the ability to save presets to a synth I'm building but I can't find a suitable I.C. for the job. Something as small as 1MBit would do, but I can't find any serial flash in DIP flavour (or anything non-surface mount).

I'm only at the prototyping and already using a SDIP28 PIC so using surface-mount memory would be a pain in the ass! The M25P10 chip (SO8, datasheet) would be perfect if it was a little bit larger, any ideas?

[Enzo]

Wow, unless you could mount it on a turret board, I am guessing that is a bit out of our collective expertise. Hopefully I will be surprised, for your sake.

Try calling Digikey and asking for applications assistance finding a suitable part.

And for that matter, at least at hobbyist levels, I often look to Jameco first when looking for memory and related ICs.

[kingsteven]

Someone on another forum just pointed me to this, should be fine for prototyping!

http://cimarrontechnology.com/index....PROD&ProdID=12

To be honest it's a bit beyond me too, I've got the DSP experience, and I've built some FX and biased some amps but my electronics knowledge (and soldering skills) aren't the best... Oh well, needed a challenge! :-)

[Steve Conner]

What's so scary about SOICs? They aren't that hard to solder. More and more good chips come in smaller and smaller packages every day. Sooner or later you will need to tool up your home workshop to handle SMDs.

To mount SOICs in my prototypes, I use pieces of stripboard with the copper tracks very carefully split lengthways with a Dremel. The pins on SOICs are exactly half the pitch of DIPs, so they line up fine. You can then use wire-wrap wire to make the transition to full-size stripboard. Or I just use those Adaptic boards if I have any handy, but they can be expensive, and some chips can't tolerate the extra stray lead inductance.

Once you learn the knack, you can solder some scarily fine pitch stuff with hand tools. Here are some I did earlier:

http://scopeboy.com/gallery/index.php?showimage=233

[kingsteven]

Heh, people tell me this all the time... but then I look at those tiny little leads and freak out a little.

TBH, it's just for convinience at the moment... I'm using a DIP28 PIC and really didn't want to mix packages (seriously obsessive compulsive soldering ) I imagine I'll switch to surface mount on my next project , but i'd like to get some better tools first.

Just to add some answers to my original question I've got from other lists/forums:

ST cross-reference guide (a bit old but lists all the major serial flash I.C.s)
http://www.st.com/stonline/products/...rflash0705.pdf

Winbond's serial flash chips come in DIP (even though it dosn't say in the datasheets) you can get them from digikey
http://www.winbond.com/

Finally: I'm seriously considering switching to an Atmel AVR... which have similar features to the Microchip MCUs but some cool aditional features like in-built self-writable flash memory!
http://www.atmel.com/products/avr/

[Steve Conner]

PICs have built-in self-writable flash memory too. I've built many things with PICs that store their settings in flash. I used the PIC16F877, but I'm sure all of the in-circuit programmable PICs are capable of it.

However, many geeks prefer AVRs, because of the free Gnu toolchain for them that lets you write in C without paying for a compiler. I've stuck with PICs just because I've designed a lot of stuff based on them in the past, and got familiar with their quirks. Better the devil you know, etc.