Recommendations on low temperature thru-hole 32768 xtal

[Bob E.]

Hello,

I have been looking through catalogues tyring to find an oscillator
crystal @32.768kHz for use in serial communications timing
(synchronous, and asynchronous), and real time clock at low
temperatures (needs a -40 C temperature spec), as well as having low
power consumption.

There are several SMT devices that fit the the bill, but all of the
thru-hole components seem to have a 0, -10, or -20 C operating
temperature specs.

Can anyone make some recommendations? Will using an oscillator below
its operating range be a fatal mistake?

Thanks for the help,

Bob

 

[Tom Woodrow]

http://pdfserv.maxim-ic.com/arpdf/DS32kHz.pdf

Bob E. wrote:

Hello,

I have been looking through catalogues tyring to find an oscillator
crystal @32.768kHz for use in serial communications timing
(synchronous, and asynchronous), and real time clock at low
temperatures (needs a -40 C temperature spec), as well as having low
power consumption.

There are several SMT devices that fit the the bill, but all of the
thru-hole components seem to have a 0, -10, or -20 C operating
temperature specs.

Can anyone make some recommendations? Will using an oscillator below
its operating range be a fatal mistake?

Thanks for the help,

Bob

 

[John Larkin]

On 8 Aug 2003 14:10:12 -0700, achillea88@yahoo.com (Bob E.) wrote:

Hello,

I have been looking through catalogues tyring to find an oscillator
crystal @32.768kHz for use in serial communications timing
(synchronous, and asynchronous), and real time clock at low
temperatures (needs a -40 C temperature spec), as well as having low
power consumption.

There are several SMT devices that fit the the bill, but all of the
thru-hole components seem to have a 0, -10, or -20 C operating
temperature specs.

Can anyone make some recommendations? Will using an oscillator below
its operating range be a fatal mistake?

Thanks for the help,

Bob

Condensation could be bad news; the Q can be killed by frost. So you
may need a nitrogen-filled gadget, or the ultimate: Micro Crystals
makes vacuum versions, but those are surface mount, too. 32K crystals
usually have a parabolic TC that peaks around room temp, so expect big
frequency errors.

LapTech makes truly beautiful, vacuum, glass packaged crystals, but
only AT cuts in glass HC18 cans.

John