I am trying to evaluate power consumption in HL78 dev-kit Rev 4. However the power consumed is really strange. When measuring power for the chip without RF, the power seems to be Okay for the chip but not for RF since they are measured separately. However, when measuring power for the chip plus RF, the power is high. The average power consumption is around 28mA in sleep mode and there are spikes up to 42 mA.
Which firmware version are you using? If you are not in the latest firmware, please download the latest one and retry.
You can get it here: HL78xx Firmware
Do you enable PSM (+ CPSMS) or eDRX (+ CEDRXS)?
Please refer to this document for more details: AirPrime - HL7800 - Low Power Modes
I am using the latest firmware (HL7800.4.5.4.0). The PSM is enabled but even though it is not, the power consumption for RF is high. Why RF consumes a lot of power?
So the key point when using the HL78 dev kit is to make sure CN804 jumper is not connected, this separates the HL78 and dev kit power supply out and means the HL78 will be powered through the power connector CN801 and the board through the jack, CN800. Are you doing this? Also what tool are you using to measure the current consumption with? An Otii?
If you are using an Otii can you post the plots you are seeing so they can be commented on?
I am exactly doing that. I was expecting to get power consumption for HL78 in NB-IoT statues (Connected, cDRX,…)
The meter I am using is Otii Arc. The plot shows two pings with 1 minute interval where the active timer is set to 0. So UE should go to PSM after the RRC connection release. The average power consumption during PSM is over 26mA.
The other thing that you might be missing is that because we are using the Altair chipset the state of the radio and the baseband have been separated out meaning that the radio can go into PSM/eDRX mode but the base band will run at full power if the Wakeup line is held in the wrong state (DIP switch next to the two yellow push buttons on the dev kit).
I have two Otii arc meters. I have tried to measure power for base band and RF separately. The base band power consumption is as expected. The issue is with the RF power consumption. For some reason, it is very high.
Not sure, if you have removed CN803 and 804 then the supplies are separated, after that if the unit is operating and entering the modes as you expect then they should be able to be measured independently as you are trying to do. Does it work i.e. come up with the right current consumption, if you don’t separate the supplies out?
RF power consumption is very high which affects the base band. If I separate them, then RF power consumption is high and the base band is OK but If I join them then, the power consumption is high as the figure shown above. What I am looking for is the power consumption of the module ( base band and RF ) and whether or not comply with the HL78 technical specification. I believe the values written there is for module ( base band and RF ).
You might need to contact who you bought the unit and kit from. There is additional material available showing all of this and the figures being correct but it can’t go over the forums.
Thank you for your help so far. Could you please specify what material I should ask for so that I forward it to the right person?
The kit was given as a gift from Sierra Wireless.
Ok so that makes support difficult, who gave it to you from Sierra? Our support is normally centered around commercial opportunities i.e. direct customers, through distribution, etc.
I was trying to document the issue to send it to support but I discovered that the high power consumption is with the base band not RF. Any idea about this issue before I file the issue to Sierra Wireless support?
The wakeup switch is off in my case and it does not make any difference when it is on.