Halo v2 - power consumption

IoT Modules Legacy HL Series
1

Hi,

I’m working with Halo V2 and I’ve got a pair of questions:

1º.- I’ve read in the “HILO V2 APPLICATION NOTE” document the two following sentences:

i) “The HiLo V2 module can be supplied by a battery or any DC/DC converter compliant with the module supply range 3.2V to 4.5V and 2.2 A.”

ii) “To start the module, first power up VBAT, which must be in the range 3.2V ~ 4.5V, and able to provide 2.2A during the TX bursts”

Then I understnad that I need a power supply of a mínimum of 2.2A. Is it ok? I ask this issue because I’ve seen a design with a linear regulator of only 1.5A/3.7V working.

2º.- The level of UART1 signals are 2.8V, and I’ve read in the “HILO V2 TECHNICAL SPECIFICATION” document that input voltage-high is a mínimum of 2.4V and Vmax in UART signals are 3.2V. Then If I need to interface this signals with a micro with 3.3V level, I’ll need a level shifter to adjust the different levels. Is it ok? I ask this issue because I’ve seen a design without these level shifter in the UART1 interface.

Thank you so much. Best regards.

2

Hi,
Please find below the answers to your querries.

  1. The power supply used for the hiloV2 must be capable to provide a peak of current for the BURST (according to the PTS the burst peak of current is 1.7A with a capacitor of 680uF).

  2. The voltage of the UART is 2.8V with +/- 0.4V of tolerance.
    If your HW is within this range in 100% of the cases (tolerance of components, HW diversity in mass prod) so you don’t have to adjust with LevelShifter.

Regards,
Rex

3

Thank you so much.

I understand the answer of the question 1, but the answer of the question 2, It’s a little confusing. I’ve seen in a HW design, the uart module conneced to a microprocessor with a voltage level of 3.3V. but I think it’s necessary to use a level shifter, due to 2.8+0.4 = 3.2V < 3.3V, Isn’t It?