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[on:]

So.... I didn't read the spec sheets thoroughly (or didn't fully take them in)  so now I need to get some logic level shifters... The devices I have are a mixture of 1.8v and 3.3v, I'm using a Boarduino (or a Duemilanove intially) which is of course a 5v device.

These little beasties look perfect for the job: http://uk.farnell.com/analog-devices/adg3301bksz/translator-sgl-ll-bidir-6sc-70/dp/2067851

Bi-directional, work from 1.15 to 5.5v, and available in 4 or 8 channel as well. Except they're SMTs and I'm already going to be suffering enough with SMTs...

There's also these: http://uk.farnell.com/on-semiconductor/mc14504bcpg/ic-4000-cmos-4504-dip16-15v/dp/9665064

DIP, so I can socket them easily, but will they do the job? I've tried reading the data sheet, but whilst it sometimes mentions 3-15v, it also mentions -0.5-15v as input ranges. 

Anyone used an MC14504 with a 1.8v chip? Will it work, or do I need to break out the magnifying glass again?

Thanks in advance.

[Reply #1 on:]

It doesn't look like a good fit. It might work, but probably not. It is only spec'ed for 5V supply and it will put out near 5V when the output is high. Is your part 5V tolerant? most low voltage parts are not.

A quick search of Farnell.com doesn't show any DIP parts that can interface to 1.8V.

Depending on how much you dislike SMD you may be able to bend the leads of an SOIC so they fit in DIP holes. I would recommend either living with the SMD or getting adapter boards like this. http://cimarrontechnology.com/sc70to6-pindipadapterpn041103b.aspx

Good luck,
Steve Turner

[Reply #2 on:]

The only SMD device I've used so far is a MAX6675 - it still works despite me melting most of the Vcc pin off... They are far too narrow to fit on a DIP socket, the legs have to be extended to reach.

I've just ordered a handful of the ADG3301 devices. Guess I'll just have to use the magnifying glass...

Given the price of those breakout boards.... I'd quite like to make my own I think...