tms3705

Yakasi -

The ez430-TMS37157 kit has the base station and ez430 target board with MSP430F2274 and TMS37157 populated. There is a small 2.66mH ferrite core SMT coil (L1)  which is used for "antenna" . So there is no integrated antenna inside the IC as this would be perhaps quite difficult to successfully achieve in the standard 4mmx4mm QFN package.

Regarding the data sent back from the TMS37157 to the TMS3705...of course this depends on the command sent, but in general, you can see page 10 of the datasheet for the memory map of the part ==> http://focus.ti.com/lit/ds/symlink/tms37157.pdf.

For overview of the TMS37157 operation/interaction with the TMS3705, please see the attached technical training that i put together - hope this helps you out.  

5657.MCU-RF and MSP430 Non-Battery Operated Wireless Solutions.pdf

hai josh

thanks for ur cooperation i am connecting ez430 to tms3705 and i am using application ckt that given in integrated tiris rf module tms2705A introduction to low frequency reader and i am using transponders like trf7960,7961 etc i would like to know whether these transponders contain built in antenna or not

Yakasi -

The TRF7960/61 are not transponders...they are HF(13.56MHz) RFID reader ICs...the TMS3705 is an LF(134.2kHz) reader IC...neither of these reader ICs has an integrated antenna, nor do any of the transponder ICs that TI offers. For finished TI transponders with antenna connected, please visit:

http://focus.ti.com/paramsearch/docs/parametricsearch.tsp?family=rfid&sectionId=475&tabId=2102&familyId=1352

you can sort by desired frequency and form factor from this link.

hai josh,

thanks for the information i want to know that the transponders RI-TRP-R4FF-30, RI-TRP-W4FF-30, RI-TRP-W9QL-30, TMS37157 CONTAIN BUILT ANTENNA OR NOT and what is the unique code that will be sent back to reader by these transponders

Yakasi -

The LF  transponders you have called out here:

RI-TRP-R4FF-30 (Read Only Card) has 64 bit unique serial # , RI-TRP-W4FF-30 (Read/Write Card) has 80 bit user space and is programmed with all 5's when shipped out and can be reprogrammed to what you want. The RI-TRP-W9QL-30 is 30mm 80 bit read/write disk transponder and also is programmed by us with all 5's before shipping.

Please see these links here for DS/Ref guides:

http://focus.ti.com/docs/prod/folders/print/ri-trp-r4ff.html

http://focus.ti.com/docs/prod/folders/print/ri-trp-w4ff.html

http://focus.ti.com/docs/prod/folders/print/ri-trp-w9ql.html

The TMS37157 is packaged tag IC with SPI interface to microcontroller which requires the addition of 2.66mH coil inductor, charge and tuning caps.

Ref Guide is here:

http://focus.ti.com/docs/prod/folders/print/tms37157.html 

hai josh,

i got tms3705 samples but i am facing difficulty in identifying which is the first pin i checked in ti site the sample wht i got doesnt have any round mark it contains a single line this is the part number tms3705A1DRG4. for frequency of operation i use 470uh with 3.3nf  instead of 440uh is it ok . and one more thing can i get  through hole ic instead of soic samples.

regards

bharath

Bharath -

The TMS3705 was never made in DIP package, sorry. If you find any, they are 100% counterfeit parts, please do not use. We had a customer in South America find some a couple years back and we traced source back to China. These DIP parts are not from TI despite being marked as such and do not function correctly (which is why he had trouble and came to us for help in the first place) Once he replaced them with known TI parts in his circuit, it worked as expected.

Regarding the marking of pin one, there are two references here for that.  one is page 21 of the data sheet, where it shows that beveled topside of the part is where pins one through eight are and the other is the link on the product page:

http://focus.ti.com/general/docs/product/topsidemarking.tsp?part=TMS3705A1DRG4&pkg=D&pin=16&actionPerformed=viewTopsideMarking#22

Which takes you to SOIC D package, which shows the stripe. Hope that clears that up for you.

Regarding the antenna, yes you can use 470uH, but the cap should then be (as 3.3nF with 470uH yields only 127kHz)  3nF or 3000pF (you can use two 1500pF in parallel) since that actually yields 134.1kHz - when you do the equation ==> fc = 1/2pi *sqrt(L*C)

hai josh,

  i am unable to see the tranmitted data on cro . i am using ez430-rf2500 usb debugger for uart communication  with a baud rate 9600 . i used ccstudio for programming . the registers uca0txbuf are getting data but in cro no signal is coming . suggest me some solution and please provide me if u have any codes for uart

Yakasi -
if you could be a little more descriptive of your setup and exactly what you are sending versus what is coming back that would be most helpful. also, what is cro?

Thanks!

sory josh,

cro means digital storage oscilloscope . i am sending a byte from com port to ez430 rf2500 usb debugger  with a baud rate of 9600 and i am checking this data on digital storage oscilloscope at txd pin. here is  the code . i m not able to see the data that i am tranmitting to txd pin i am using ccstudio for programming and the code works perfectly and the registers that are used for uart are getting updated with the values used in the program. please suggest any solution for this and if u have any codes related to transmission and reception with uart please share them.

void

Yakasi -

are we still talking about TMS3705 or are you now talkign about the RF2500? This is not clear to me.

Thanks!

hai josh

i am still talking about tms3705. i m using r/w transponders that are compatible with tms3705(corresponds to 134khz) in order to send the data to transponder through tms3705 i am using ez430 which contains msp430f2274 microcontroller so initally i m testing uart communication between the ez430 and my pc later i will interface it with tms3705. i m interested to see the output from tms3705 on a digital storage oscilloscope. so initially i started uart communication between my pc and ez430 i am unable to see the transmitted data on digital storage oscilloscope.

thanks

bharath

OK - so if i understand this correctly - you are currently not hooked up to the TMS3705 via the MSP430F2274 onboard target board, but rather currently only looking at communication from USB debugger to the MSP430F2274 on the target board. I think if you check out page 10 of the ez430-RF2500 Dev Tool guide, this may be where you need to start in order to ensure good communication with the backchannel UART. http://focus.ti.com/lit/ug/slau227e/slau227e.pdf 

hai josh,

i m facing some problem in getting the data back from transponder i m using

RI-TRP-R4FF, RI-TRP-W4FF Lf transponders  and one more thing according to timing diagrams given in tms3705data sheet in that look into default mode i am applying the timing signal at txct pin i dodnt know hoe to generate a pulse of tint=2msec,tch=3msec and after that txct shoulde be high for 20msec inorder to get the data at scio pin, if u have any programs relating to this please send me

Bharath -

Please see attached regarding TMS3705 and RO/RW tags.

6518.Notes on TMS3705A1DRG4 & Read.ppt

 also, general training on the TMS3705

3301.LF TMS3705A ASIC.ppt

Hi Josh,

We are using Asynchronous mode of data transfer from TMS3705 to microcontroller. we receive the data but when we decode the captured data we are not getting Tag ID.

The have inverted the data after rotating the LSB and MSB. But its not valid data.

Can you please help us in this issue. we tried as per the PPT.

http://e2e.ti.com/cfs-file.ashx/__key/CommunityServer-Discussions-Components-Files/667/3301.LF-TMS3705A-ASIC.ppt]

Sreekanth