Power consumption in Sleep mode (Vbat /battery powered)

In HTCC-AB01,the typical value of Power consumption in Sleep mode is 11uA in spec.

However, my measurement is different:
Vbat Sleep mode Current (Vbat /battery powered)
3.5V 10.7uA
3.7V 10.9uA
4.0V 22.9uA
4.2V 27.1uA
Which means it will almost triple Power consumption when li-ion fully charged.
Is it normal? where the power was gone and how to reduce it?

Also,I use a tweezer to short the charging IC input (Vs) to GND but the current does not change.

hi,

you can refer this picture.

The Sleep mode (Vbat /battery powered) show in the picture is 11uA.
I can get a similar current(10.9uA) when Vbat is 3.7V.
However, it becomes 27.1uA when Vbat is 4.2V. Is it correct reading?

Yes, “27.1uA when Vbat is 4.2V”.

We recommend using 3.7V

On my HTCC-AB01, the BR0 is connected to AO7801 S1, not D1.
It creates a sink current to the ADC pin and pullup the Vdd from 3.3V to 3.4V.

After I remove BR1 and use a jumper wire connect ADC to D1 , the Sleep mode Current (Vbat /battery powered) at 4.2V will be normal and 3.3V power does not goes higher.

Also, I found out HTCC-AB01 using 2 10k resistors as a voltage divider, but HTCC-AB02 using 2 100k resistors as a voltage divider. I replace 10k with 100k without any issue and reduce current consumption during battery voltage sampling.
image

hi,

Thank you so much for your creative opinions.

Actually, We were also considering this issue some time ago. Your ideas coincide with ours.

We will also produce the latest hardware version in the near future.

Hi Jason,
if you are going to change the PCB for the next version please expose the enable pad on the onboard regulator so that an external one can be added as a backup. (see the other thread on secondary backup battery)

thanks

OK. We will add this in the next PCB version

I have a similar issue with my HTCC-AB01 consuming higher current in Sleep mode.
Do you have a sketch of where the AO7801 and the BR1 are located on the board so that I can check whether mine has a connection to S1 rather than D1?

Just reminded that we are talking battery power.


Here is how I modified my board.
image

Thanks, that is perfect. I have two identical circuits and I can see one draws about twice the battery current as the other, so I will now check the board to see if the thirsty one has the S1 connection instead of the D1 connection.

Hello , Can I see your code ? I can not reach 11uA, my code only has 450uA, how can i reduce consumption?

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hello,

What the version of AB-01 need to be modified to have low power consumption in sleep mode?
I have AB-01 ver. 1.2 and test sleep example give me 0.04mA of consumption.
As can I see my board also have these small resistors…
Also it would be good to see the code.
thank you.

hello again…

I modified my AB-01 board - removed resistor and soldered jumper as it showed on the picture above.
But current in sleep mode still the same - 0.04mA

How are you measuring the current draw?

The follow-up question would then be “Is that multimeter capable of accurately measuring current down in the µA range?”

But what’s that connected to the USB port? I don’t recall whether or not it was a CubeCell or some other board, but I do recall that there was an issue at some point that, if something was connected to the USB port, the CP2102 remained active and drawing current.

please be sure that this is good multimeter - I use it for measure current around 8-9uA for another devices the same way.

in USB port connected simple USB adapter - micro-USB - type-C
like this:
image

and of course I checked without it - the same value of current - 0.04mA

I have two of AB-01 ver 1.2 boards.
one board already modified, and both shows the same current in sleep mode…

is this modifications also need to be done to receive correct power consumption during sleep mode?
if so - where is these 10k resistors located on the board?
both need to be replaced by 100k?

any answer or advice?
anyone else experienced similar issues with sleep mode?
is it possible that I have some “broken” or bad devices of AB-01?

UPD: Also I have 2 AB-02 devices V 1.0 - both of these devices shows 13uA of power consumption with the same code as I use for AB-01 boards.
So totally I have:
all powered via JST connector from LiPo 4v:

AB-01 V 1.2 - 0.04mA sleep mode
AB-01 V 1.2 modified (removed resistor and jumper connected )- 0.04mA sleep mode
two of AB-02 V 1.0 - 13uA sleep mode

this is very strange and I totally disappointed…
when I read the specs of CubeCell - first thing I saw was 3.5uA sleep mode consumptions and because of this I decided to use these devices…
any advices would be very helpful because I have already a lot of AB-01 which I planned to use in my project where I need deep sleep mode.