SIM7600e problem with 1v8 output oscillating

[Blackwarrior]

dear forum

i have designed a circuit using the 7600e with an ESp32 processor
the 1.8v output on the 7600 is oscillating at 1.695 Hz, with an on time of 534mS and off time of 62mS, this also applys to the I2Cclock and the PCM data pins

these 10 SIM7600e's that ive bought differ in P/N numbers to the prototype i already have working OK, excactly the same circuit but different chips

can anyone please advise on the fault
many thanks
Tony

 

[KlausST]

Hi,

ther´s no error description, nor a question.

So maybe it is meant to work this way.

But if you want us to review your circuit, you need to show us your circuit. Schematic, photos (100kby each), PCB layout.
And a clear error description:
* test conditions
* expectation
* what´s not like expected

Klaus

 

[Blackwarrior]

Hi Klaus, thanks for your reply

this circuit works fine with a different SIM7600E chip, so i doubt its the circuit.

problem is the 1.8v output voltage i use for level shifting on the uart to esp32 is oscillating, there is no status led on, therefore chip isnt active, no comms between sim7600 and esp32.
im wondering if the sim7600e has different firmware in it, or corrupt firmware


see attached schematic and layout
many thanks
tony

 

[D.A.(Tony)Stewart]

I believe this device is not rated for 1.2V. Can you offer more clues to this crystal ball question?

Voltage - Supply

3.4V ~ 4.2V

 

[Blackwarrior]

Hi Tony

The chip has an output pin of 1.8 volts used mainly for level shifting which i use.

I think the sim7600e has a firmware issue. The circuit performs well with a different 7600e chip so im convinced this is the issue.

Ive searched for pc software that will allow me to reflash the 7600 but all i find is in chinese and cant use it

Thanks
Tony

Ps the supply voltage for this is 3.94 volts

 

[D.A.(Tony)Stewart]

I'm sure there must be an English version or I can translate it in my browser extension, if you need it. There are some Japanese tools in English , I recall.

--- Updated Jan 14, 2024 ---

Does this work?

SIMCom SIM7600E CAT-1 mPCIe | 4G LTE | Techship

SIMCom SIM7600E is Multi-Band LTE-TDD/LTE-FDD module solution in a mPCIe form factor. SIM7600E is a LTE CAT-1 module with support of up to 10Mbps downlink data transfer.

techship.com

 

[Blackwarrior]

Hi Tony

If you have a link to an english version i would really appreciate it.

Many thanks
Tony