Android Check Battery Capacity

1. Android Phone Check Battery Health
2. Android Battery Cycles

Android calculates battery usage using pre-baked profiles that device manufacturers provide, like how much power the CPU uses. In practice however, these numbers tend to be highly inaccurate. When you tap on Battery Health, you can easily see the relevant statistics. Maximum Capacity is a percentage that measures current capacity versus 100% when your battery was new. A range of that. The Android operating system has a feature called Battery Stats, which keeps track of battery capacity, when it is full or empty. The problem is that it sometimes becomes corrupted and starts displaying data that isn't real, which, for example, causes the phone to turn off before it reaches 0 percent. AlarmClock; BlockedNumberContract; BlockedNumberContract.BlockedNumbers; Browser; CalendarContract; CalendarContract.Attendees; CalendarContract.CalendarAlerts.

You can determine device power consumption for Android devices that include a battery fuel gaugesuch as a Summit SMB347 or Maxim MAX17050 (available on many Nexus devices). Use the in-systemgauge when external measurement equipment is not available or is inconvenient toconnect to a device (such as in mobile usage).

Measurements can include instantaneous current, remaining charge, battery capacity at test startand end, and more depending on the supported properties of the device (see below). For bestresults, perform device power measurements during long-running A/B tests that use the same devicetype with the same fuel gauge and same current sense resistor. Ensure the starting battery chargeis the same for each device to avoid differing fuel gauge behavior at different points in thebattery discharge curve.

Even with identical test environments, measurements are not guaranteed to be of high absoluteaccuracy. However, most inaccuracies specific to the fuel gauge and sense resistor are consistentbetween test runs, making comparisons between identical devices useful. We recommend runningmultiple tests in different configurations to identify significant differences and relative powerconsumption between configurations.

Reading power consumption

Istudiez pro 1 4 – student planner with ios syncing. To read power consumption data, insert calls to the API in your testing code.

Available properties

Android supports the following battery fuel gauge properties:

Most properties are read from kernel power_supply subsystem attributes of similar names.However, the exact properties, resolution of property values, and update frequencyavailable for a specific device depend on:

• Fuel gauge hardware, such as a Summit SMB347 or Maxim MAX17050.
• Fuel gauge-to-system connection, such as the value of external current sense resistors.
• Fuel gauge chip software configuration, such as values chosen for average current computationintervals in the kernel driver.

For details, see the properties available for Nexus devices.

Maxim fuel gauge

When determining battery state-of-charge over a long period of time, the Maxim fuel gauge(MAX17050, BC15) corrects for coulomb-counter offset measurements. For measurements made over ashort period of time (such as power consumption metering tests), the fuel gauge does not makecorrections, making the offset the primary source of error when current measurements are too small(although no amount of time can eliminate the offset error completely).

For a typical 10mOhm sense resistor design, the offset current should be better than 1.5mA,meaning any measurement is +/-1.5mA (PCBoard layout can also affect this variation). For example,when measuring a large current (200mA) you can expect the following:

• 2mA (1% gain error of 200mA due to fuel gauge gain error)
• +2mA (1% gain error of 200mA due to sense resistor error)
• +1.5mA (current sense offset error from fuel gauge)

The total error is 5.5mA (2.75%). Compare this to a medium current (50mA) where the same errorpercentages give a total error of 7% or to a small current (15mA) where +/-1.5mA gives a totalerror of 10%.

For best results, we recommend measuring greater than 20mA. Gain measurement errors aresystematic and repeatable, enabling you to test a device in multiple modes and get clean relativemeasurements (with exceptions for the 1.5mA offset).

For +/-100uA relative measurements, required measurement time depends on:

• ADC sampling noise. The MAX17050 with its normal factory configuration produces +/-1.5mAsample-to-sample variation due to noise, with each sample delivered at 175.8ms. You can expect arough +/-100uA for a 1 minute test window and a clean 3-sigma noise less than 100uA (or 1-sigmanoise at 33uA) for a 6 minute test window.
• Sample Aliasing because of load variation. Variation exaggerates errors, so for sampleswith variation inherent in the loading, consider using a longer test window.

Supported Nexus devices

Android Phone Check Battery Health

Android Battery Cycles