E series LTE peak current consumption

General
1

I have two questions:
I checked the E series datasheet and there isn’t specific information available on the peak current consumption of the LTE version. I checked ublox module’s datasheet and it appears that the peak current consumption is 490mA. Can I assume that LTE version’s peak current is 500mA?

I have a second question: According to the SARA-U2 series datasheet (used in 3G models), the peak current is 1.9A. I came across this E-series pdf that indicates that the peak current is 800mA for the 3G version. Which one is correct?

2

We will need to know what voltage you’re sending into which pin. If it’s 3.7VDC into the Lipo pin, Ipk < 1A typically for the electron-only, which is very close to the E series except for the layout. A 500 mA supply will definitely give you brownouts.

Obviously, your mileage will vary depending on support hardware, input voltage, etc.

3

I am not using a battery. I am using a 5V 2A power supply for my Electron. I am using the same for 3G E series as well.

I am trying to determine the power supply requirements for the LTE version of the E series.

4

FWIW, the LiPo pin can be used with a power supply (approx. 3.5<=LiPo<=4.2V). It is the most power efficient way to run the Electron or the E-series. The reason the voltage matters is that there is a switch-mode converter (actually a couple) that are on board.

2A @ 5VDC should be sufficient with the Electron in LTE. My understanding of the 3G device is that it indeed pulls up to 2A, so 2A would be the minimum, you might want some headroom there. I’ve seen recommendations on here for a considerable amount of bulk capacitance if a battery is not present, up to 1000 uA, so you may want one or more electrolytics or aluminum polymer caps on the input.

As always, your mileage may vary, and I’d recommend testing with a high-speed logging multimeter on the input to make sure the voltage rail is behaving the way you think. An oscope could be used as well, but you may need to use two channels to see that large voltage range between idle and transmitting.

5

The 5V 2A supply is working out for me. I tested it under different scenarios and I am happy with it. There have been occasions where I wanted to bump it up but I got away with sticking to a 2A source.

Now that the LTE E series has arrived, I wanted to make sure that I could the same source.

Due to the nature of my application, I cannot use a LiPo battery.