I'm new to circuit design. I'm using an Injoinic IP5306 battery charging IC (datasheet). I also use an AMS1117-3.3 (datasheet) to drop down the 5V power it produces to 3.3V. I've attached a picture of my schematic which shows the relevant portions, the IP5306 in single-LED configuration, the AMS1117-3.3 circuit, and the 4 WS2812B LEDs (datasheet) that I'm trying to drive. The batter terminals connect to a Li-ion 18650 battery.

## Problem Description

When running on battery power, this circuit works for about 33 seconds and then "fails and shuts off". When running on 5V USB power it runs forever, and also correctly charges the battery. I state it "works" because I can program the test pattern which drives the LEDs as expected. When it "fails and shuts off" it shows this soft blinking red pattern.

Here's a video showing the problem:

Voltage measurements of the AMS1117-3.3 pins show: The 5V input is fluctuating between 1.55 - 1.67 V which is creating the red blinking effect for the LEDs. The AMS1117 pin for 3.3V output is fluctuating between 0.72 and 0.82. I have a few independant hardware devices so I think it's safe to say this is a design issue. The power at the battery when it's supplying power is ~ 4.0 V.

## Questions

What is the flow the unexpected power is taking in my circuit?
Why does it was 33 seconds to power off?
What tools and techniques do I need to learn to analyze these types of failures?
Do you see a problem with my schematic?

Thank you!
Brian

 

These power bank "all in one"-chips are often used for cell phone charging applications and load current is measured. If the chip detects "cell phone" is not there, it will shut down by itself to save power.

Here you have the datasheet in English, and on page 6 you see:





English datasheet:
http://www.injoinic.com/wwwroot/uploads/files/20200221/0405f23c247a34d3990ae100c8b20a27.pdf

 

Ah yes! Thanks for pointing that out. When I run a brighter pattern it stays on continuously!

I'd like to run workloads < 45mA, is there another IC or set of ICs that would be a better fit than the IP5306?

Also when I manually put it into standby mode, there is the question of the stray voltage on the 5V boost line. One area where the data sheet (here is english version) was a little confusing to me is the 1LED option on page 7, which this schematic uses. In the schematic, the label BAT_3.7V is attached to R8, which perhaps is how the power is coming from the battery to create 1.55 - 1.67 V on the LED_5V line. Maybe I should have attached the left-side of R8 to ground? Maybe I should add a diode? What can I do to figure this part out?

 

Ah yes! Thanks for pointing that out. When I run a brighter pattern it stays on continuously!

I'd like to run workloads < 45mA, is there another IC or set of ICs that would be a better fit than the IP5306?

Also when I manually put it into standby mode, there is the question of the stray voltage on the 5V boost line. One area where the data sheet (here is english version) was a little confusing to me is the 1LED option on page 7, which this schematic uses. In the schematic, the label BAT_3.7V is attached to R8, which perhaps is how the power is coming from the battery to create 1.55 - 1.67 V on the LED_5V line. Maybe I should have attached the left-side of R8 to ground? Maybe I should add a diode? What can I do to figure this part out?

The datasheet shows the key function as the following:

Push button’s connecting is shown in Fig 5. IP5306 can identify long push and short push.
- If button is pushed longer than 30ms but shorter than 2s, IP5306 will identify the action as short push. Short push will open SOC indicator LEDs and step-up converter
- If button is pushed longer than 2s, IP5306 will identify the action as long push. Long push will close step-up convertor, SOC indicator LED and flashlight LED.
- If button is pushed shorter than 30ms, IP5306 will ignore the action.
- If two short push is detected within 1s, IP5306 will open or close flashlight LED

Can you have the microcontroller emulate the button press with a transistor for the purpose of "pressing" the button every 20-30s to keep it alive?