hi all
we did ESD testing on the SIM connector connected to a SIM300D module in power off state.
Before the test everything was working fine
But after the test i am constantly getting on request of AT+CPIN?
CPIN: SIM ERROR
my VDD_SIM is showing 0V.
one thing i would like to mention is that my schematic is according to the Reference Schematics of SIM300 EVB. All the caps and transzorbs SMF05c are in Place.
i also tried powering the SIM using a 3.3V supply instead of Internal regulator but no use.
hi all
we did ESD testing on the SIM connector connected to a SIM300D module in power off state.
Before the test everything was working fine
But after the test i am constantly getting on request of AT+CPIN?
CPIN: SIM ERROR
my VDD_SIM is showing 0V.
one thing i would like to mention is that my schematic is according to the Reference Schematics of SIM300 EVB. All the caps and transzorbs SMF05c are in Place.
SIM card was not there in the connector
the Discharge was 6KV direct contact on the SIM connector i.e. on VDDSIM SIM DATA and CLK lines.
the SIM module when replaced worked fine on the same board.
the module which was under tested did not work on other board too.
so its clear that the module is going bad
The sim300 module work fine with sim-cards of 2.8 - 3.0 vol. But don´t work with the sim-cards of 1,8 vol.
My test board has all fine. It has the capacitor of 0.22 uF, also the TVS and the resitor pull up between VDD_SIM and DATA_SIM (10K).
I do not see the problem.
Thanks, your answer is very useful because some SIM-CARDs of 3 Vol not working and now working very well. But my problem with the sim-cards for 1.8 still persists.
are u using a 6 pin connector or 8 pin connector...
one more thing is that you can increase the value on the Vsim line to 100E.
logic basically is that VSIM supply is 2.8V and current consumption by SIM card is MAX 10mA. so 10mA * 100E = 1V.. so that total the VDD at SIM line would be 2.8V-1V = 1.8V
one more try wat you can do is power VSIM externally using 1.8V regulator.
please check and lemme know
and what you propose, I do not understand very well, but to increase the value of series resistance of 50 ohms to 100 ohms for any 3 volt cards these stop working.
the idea of external regulation is feasible, but the goal is simply to work the 3-volt and 1.8 without distinction.
hi dere i m working on sim300
n i wnt 2 cnct microcontroler to sim 300
coud u hlp m wd d fact hw 2 convert at commands to ira character set so tat i cn snd sms frm microcontroler
i also hv another problem
i did snd sms frm d sim frm pd usng at+cmgs command
bt now d same is failng
+cms error 515
This thread is being cluttered with a lot of posts that have nothing to do with the orignal topic. I wish you would follow the forum rules and start a new thread. I have the answer to your question on the CMS 515 error, but I won't post it here. I'll start a new post for it - as it should be.