Pycom G01 deep sleep current

[jroorda]

Hi all,

I've been testing with a G01 for a battery powered application on LTE-M. Unfortunately I cant get the module to operate at an acceptable deep sleep current (20-50uA would be acceptable). Lowest I could get is 270uA, see test cases and results below.

I'm not exactly sure again what results i got with various codes, but never below 270uA is for sure. I'll try to add results per code block later today.

Would like to get some advice or if someone else could do some testing as well, that would be great.

---

Hardware setup
Pycom G01

• 3.3v connected to 3v3 and 3.2-5-5v inputs (powered by external bench PSU)
• 100nf cap on 3v3 net and SIM VCC
• SIM holder installed + sim inserted
• reset button + 1M external pull-up from 3v3

---

Firmware versions:

Welcome to the SQN3330 firmware updater [1.2.6]
GPy with firmware version 1.20.2.r3
Your modem is in application mode. Here is the current version:
UE5.0.0.0d
LR5.1.1.0-47510

---

I've tried the following methods:

import machine
machine.deepsleep()

import machine
from network import LTE
lte = LTE()
lte.init()
lte.deinit()
machine.deepsleep()

import machine
from network import LTE
lte = LTE()
lte.init()
lte.attach()
lte.detach()
lte.deinit()
machine.deepsleep()

import machine
from network import LTE
wlan = WLAN()
wlan.init()
wlan.deinit()
lte = LTE()
lte.init()
lte.attach()
lte.detach()
lte.deinit()
machine.deepsleep()

[jroorda]

Results:

import machine
machine.deepsleep()

result: 260 uA

import machine
from network import LTE
lte = LTE()
lte.init()
lte.deinit()
machine.deepsleep()

result: 260 uA

import machine
from network import LTE
lte = LTE()
lte.init()
lte.attach()
lte.detach()
lte.deinit()
machine.deepsleep()

result: 19.8 mA

import machine
from network import LTE
wlan = WLAN()
wlan.init()
wlan.deinit()
lte = LTE()
lte.init()
lte.attach()
lte.detach()
lte.deinit()
machine.deepsleep()

result: 19.8 mA

[Gijs]

(Silently tagging @peterp in this)

[peterp]

@jroorda Could you update the modem firmware to CATM1 41065 and repeat your tests?

[jroorda]

@peterp Will try!

I did another test today, with a G01 where i could disconnect the LTE power supply seperately (The 3.2-5.5v input), and discovered that during deepsleep with a disconnected LTE power supply, the module only uses 28uA, which means the LTE modem draws a big amount of current.

I'll try to update the modem firmware, hopefully this solves the issue.

[jroorda]

@peterp Unfortunately the modem update over USB does not work for me. The python script on the PC hangs at "Trying to wake up via AT command".

Do you have suggestions on how to fix that? Unfortunately my board does not have an SD card reader.

[Gijs]

Could you try that over USB, with the debug flag set in sqnsupgrade.run(..., debug=True) and you can check if the sqnsupgrade.uart(True) worked correctly by typing AT commands in the REPL after that (it will link the UART of the LTE modem straight into the UART used by the REPL)

[jroorda]

@peterp After updating the modem to CAT M1 41065 I got deep sleep currents of 20uA!

I tried that with a GPy, updating the G01 over uart with a supply voltage of 3.3v for both the ESP and the sequans modem did not work. The GPy is supplied with 5v on the Vin pin, I suspect the problem with the G01 to be the low supply voltage for the sequans modem.