mini acceleration switch prefer SMT 1

[firenock]

I urgently need to locate a mini acceleration switch for my application. It will be high volume, 1-5 million in quantity or better when in final production. It have to be really TINY and light weight. Packaging is not as critical since we do epoxy coated the entire unit. The current unit we use used a reed switch. Due to difficult situation, we cannot use a magnet, and we truly believe the only other way to improve upon and maintain the functionality of the application is to use acceleration switch that can detect reliably the acceleration (150 fps). The reed switch we current use is SRC UM23XX. Any one who have info or idea please advice ASAP.

 

[MacGyverS2000]

For even 1 mill units (your lower end), a 100k investment in research is a paltry 10 cent increase in unit price... how tight is your budget?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[itsmoked]

Been down that road.

Dan that is just the start. The down payment. I would expect the price to be about 5-8x that.



Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[VEBill]

Inspired by this thread (and some new high-tech toys that I bought recently), I've formulated a new rule-of-thumb:


Designing and manufacturing highly-minaturized high-tech devices is relatively straightforward compared with sourcing suitable highly-minaturized components.

 

[itsmoked]

That would be accurate.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[tinyaccel]

cannot agree more

 

[adastra]

There are many types of digital pedometers on the market. They all operate by sensing a slight AC vertical acceleration superimposed onto 1 g DC. Usually a coiled spring moves a small magnet that hovers over a hall effect xdcr. For a 5 g application, this concept could probably be miniaturized; have you considered a simple snap action switch with the appropriate seismic mass/spring?

 

[tinyaccel]

Not yet, but it sure sounded like something I need to look into immediately.

many thank

 

[Strong]

Have you looked at piezo film? The material is self generating, so only a charge detector might be needed for acceleration level measurement. Here is a Web link:

http://www.meas-spec.com/myMeas/sensors/piezoAccelerometer.asp

They sell packaged accelerometers and piezo material that you could adapt to your own needs.

Walt

 

[tinyaccel]

Piezo film is a very interesting approach. the only down side I can see is that it do require IC to make it work. The space I have do not allow me to have all those and the wight is another significant issue. Not to mention the power source which is 25mA battery. I e-mailed them and see what suggestions they have. FYI, the entire application is 5 mm diameter X 30 mm length, and weighted 1.2 gram complete with the battery.

 

[Strong]

Here are a few more extreme micro accelerometers:

http://micromachine.stanford.edu/~kuanlinc/Professional/Mini Accelerometer.html

"By utilizing the thin film deposition technique, we fabricated one of the world smallest milli-g resolution, packaged accelerometer. The size of the whole packaged accelerometer is 500x500x300 µm, giving the weight around 200 nano-gram."

http://www.endevco.com/product/Product.aspx?product_id=20

Low cost/OEM applications
High output efficiency
Light weight (85 mg)
For SMT installation

http://www.silicondesigns.com/Prod.html#SMTaccels

» Hermetically Sealed, 20 Pin LCC or J-Lead
» Small Size 0.350"sq. x 0.10"
» Light Weight: 0.62 g (0.68g J-Lead)
» +5V Operation

Walt

 

[tinyaccel]

Thanks Strong for locating all those Accelerometers. The only issue is that everyone of them use power. I need a real switch that do not draw ANY power. So accelerometers are all but out. In order to get 5 years shelf life base on a 25mA battery, any power usage is unacceptable.

 

[MacGyverS2000]

It sounds like you'll either have to bite the bullet and pay some NRE fees to a company to make one, or bite another bullet and design it in house. I don't know what kind of repeatability you can achieve, but a single wire inside of a spring with a known (and accurate) lateral spring rate would certainly solve your problem... or give you gray hairs.


Dan - Owner

http://www.Hi-TecDesigns.com

 

[tinyaccel]

I end up doing both. Can you believe the difference in price of what is made in US and in China? The strange thing is that they both use chinese parts.