sim7090G does not want to start

[fanfan69]

hello, I bought 6 sim7090g modules, the six do not want to start, I specify that I bought them on alixepress from three different suppliers, using PWRKEY nothing happens on the pin we have a voltage of 1.7 volts

 

[KlausST]

Hi,

not much information we can validate or work with.

So my recommendation:
* read the datasheet carefully
* follow the datasheet rules and requirements
* I´d say there is more than 90% chance that they will work .. when treating them properly-

Klaus

 

[std_match]

You must temporarily connect the PWRKEY pin to GND to power up the module.

 

[fanfan69]

thank you for your answers, I set PWRKEY to GND but no response, here is a simplified diagram of my PCB

 

[aliarifat794]

Please check if your power supply is sufficient.

 

[fanfan69]

my battery is 2600mah 3.8v and 9.88wh

 

[KlausST]

Hi,

I never use this module ...

but it has a power supply pin named with VBAT. Obviously the abbreviation for "battery voltage".
My I ask why you did not connect it to your battery?

Klaus

 

[Aussie Susan]

Also what does "...do not want to start..." mean?
What tests have you done?
What does work as you expect and what doesn't - and for the last part what do you expect and what do you get?
Applying proper testing processes and describing them clearly will help everyone understand what is happening.
Susan

 

[fanfan69]

thank you for your answers, hello KlausST, the battery is correctly connected the Vbat is a netflag which powers another component on the PCB, hello Aussie Susan, I mean that nothing happens when powering up even with the PWRKEY, the status LED does not light up, the module does not respond to any AT command, I am sure that it is powered because I have the right voltage on the PWRKEY.

 

[std_match]

thank you for your answers, hello KlausST, the battery is correctly connected the Vbat is a netflag which powers another component on the PCB, hello Aussie Susan, I mean that nothing happens when powering up even with the PWRKEY, the status LED does not light up, the module does not respond to any AT command, I am sure that it is powered because I have the right voltage on the PWRKEY.

There is no "right voltage" for the PWRKEY pin. It must be pulsed to GND for switching the module on/off.
First, let the VBAT voltage rise and stabilize with the PWRKEY pin disconnected.
To power up/down, connect the PWRKEY pin to GND for about 2 seconds, then disconnect the pin again.

 

[fanfan69]

I know that I read the entire technical sheet and there is good voltage on PWRKEY here is an extract from the sheet
"The level is 1.5V when this
PIN is floating;
PWRKEY should never be
pulled down to GND
permanently."

 

[KlausST]

Hi,

I fully agree with std_match.

Please give useful and complete informations.

Please check if your power supply is sufficient.

I can only repeat. --> use a scope to show the power supply pin voltage.

on the pin we have a voltage of 1.7 volts

on which pin?

here is a simplified diagram of my PCB

Why only simplified? We need to see the whole story. Show the full schematic

my battery is 2600mah 3.8v and 9.88wh

These all are theoretical / nominal values. But don´t tell what the SIM module sees.
The battery may be old, discharged, bad connection, ... we don´t know ... thus we asked you to check.

the battery is correctly connected

I don´t know what you call "correctly"
It still is not according the datasheet.

Also the datasheet tells: "the power supply capability must be up to 500mA." ..
How can you guarantee this while using a regulator specified for 250mA only?

when powering up even with the PWRKEY

What does "even with the POWERKEY" .. mean?


Here a half of information, there a half of information ... I guess it´s time for me to leave. Good luck

Klaus