> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Kevin wrote:
>> Hi,
>>
>> I use a home grown proto board (5V) with a PIC16F88
>> w/bootloader and a Max232 chip to load programs via the pc serial port.
>>
>> I would like to communicate to a TI CC1101 chip via SPI. The
>> TI CC1101 radio chip has voltage range of 1.8V to 3.6V. Does
>> anybody have a simple level conversion circuit or a favorite
>> chip they use to convert the 5V to 3V and vice versus ?
>>
>>
>> Thanks,
>> Kevin
>
> The circuit in
> http://www.nxp.com/acrobat_download/applicationnotes/AN97055.pdf
> is what I normally use to convert between two voltage levels.
>
> Many people will tell you that you can use a voltage divider for 5v -> 3v
> and rely on the 5v logic's 2.5v threshold for 3v -> 5v conversion. This
> may work but it is not bidirectional and sounds a bit iffy.
>

For 3.3V to 5V logic level conversion, I use some sort of 74HCT chip. The
T makes Vih low enough to accept 3.3V logic levels.

Harold

-- 
FCC Rules Updated Daily at http://www.hallikainen.com - Advertising
opportunities available!
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist