TDC1000-TDC7200EVM test cell and transducer questions.

Cameron Weeks

Hi,

I have just obtained a TDC1000-TDC7200EVM, the user guide suggests on page 10 that a test cell is included, I quote "Note: the default settings work
correctly for the test cell provided."

I have a transducer but no test cell as pictured on page 9. Am I missing the test cell or is in no longer provided ? It's confusing as neither the transducer or the test cell is mentioned in the "Package Contents" on page 6.

If it is no longer provided what is the method of choice for attaching the transducer to my plastic cup (test cell). Epoxy ? I presume you must try to remove all air bubbles ? Anything else to note ?

Finally what is the part number and manufacturer for the provided transducer ?

Many thanks.
Cam.

over 10 years ago

0 Koyo Kegasa over 10 years ago

Expert 1260 points

I think the "provided transducer" is the one below.

www.steminc.com/.../piezo-ceramic-disc-1-mhz

Piezo Ceramic Disc 1 MHz
Piezo Ceramic Disc 15mmx2.1mm 1 MHz, R, Wire Leads
Manufacturer part number: SMD15T21R111WL
Availability:
We have 736 in stock (sets)
$12.50 /2 Pcs Set
Shipping: $51.75
Shipping Each Additional unit: $0.00

I used DiChloroMethane = CH2Cl2 to attach it on Acrylic Display Case.
It is not good for your health.
How about
www.krazyglue.com/.../all-purpose-krazy-glue

0 Matthew Minasi over 10 years ago

TI__Expert 4725 points

Cam,

We used to offer a "test cell" as a separate item but discontinued it.

We switched to including a transducer with the EVM.

For transducer selection and mounting techniques can read my app note: www.ti.com/.../snaa266

or watch my video: http://bcove.me/m3ojrfh3

As for gluing methods you will want to pick a non-compressible adhesive as the more flexible it is the more acoustic energy will be lost in transmission/reception. In general the transducer can be attached externally to plastic or metal containers.

What is your application?

Best Regards,

0 Cameron Weeks over 10 years ago in reply to Matthew Minasi

Prodigy 30 points

Hi Matthew and Koyo,

Excellent replies, all points read and understood, thanks guys.

My application is specific gravity sensing of a more or less aqueous solution. Sensing distance around 600mm round trip. I am aiming for an external sensor and the container will be polythene. I realize the polythene will cause problems with adhesives, but I think that can be helped with this https://www.deluxematerials.co.uk/gb/rc-modelling/18-tricky-stick-5060243901255.html

I have always strongly doubted anything that suggests it is capable of sticking polythene, at least with a sensible price tag. This however I can confirm will allow Krazy glue (Cyanoacrylate) to stick two polythene items together to the point it's the polythene that breaks and not the glue.

Thanks again chaps !

Cam.

Thanks.

Cam.

0 Matthew Minasi over 10 years ago in reply to Cameron Weeks

TI__Expert 4725 points

Cam,

I have used CA to glue transducers to multiple surfaces including HDPE (High density Poly Ethylene) for experiments. The key is surface preparation. Just follow the steps in my appnote (previously listed). I've attached them to various versions of PE (auto tanks etc.) with good resutls. A few more points:

1. Not all CA glues are the same. I use a verison that has some latex in it to allow for some "give" in the bond so it will flex before cracking while still being incompressible. See below:http://www.amazon.com/Insta-flex-clear-rubber-Bob-Smith/dp/B002N4UD3U/ref=lp_11859891011_1_16?srs=11859891011&ie=UTF8&qid=1445555823&sr=8-16

2. As for the poly failing before the glue, a company out here in California has a product that claims to "weld" PE. I haven't tried it but it looks promising. see below:

http://www.tapplastics.com/product/repair_products/plastic_adhesives/tap_poly_weld_adhesive/435

Best Regards,

0 Cameron Weeks over 10 years ago in reply to Matthew Minasi

Prodigy 30 points

Excellent, this certainly gives me enough to be getting on with.

Thanks again.

Cam.

Sensors

Sensors forum

TDC1000-TDC7200EVM test cell and transducer questions.