Ampere

설명 Ampere

Site Editorial Commentary：Measure the charging and discharging current of your battery.

Ever wondered why some chargers or USB cables seem to charge your device faster than others? With Ampere, you can finally put that to the test.

Ampere allows you to accurately measure the charging and discharging current of your device's battery. This helps you identify the best charger and USB cable combination for optimal charging speeds.

**PRO Features:**
- Home Screen Widgets: Quickly monitor charging status from your home screen.
- Customizable Notifications: Stay informed about charging levels and status.
- Device Alerts: Receive alerts for specific charging events or battery levels.
- Android Wear Support: Monitor your device's charging on your Android Wear smartwatch.

Important note: Due to hardware limitations, Ampere may not be compatible with all devices. Some devices lack the necessary measurement chip or interface required for accurate readings. Please refer to the list of unsupported devices at the end of this description.

Disclaimer: Ampere is intended as an evaluation tool and is not designed to provide precise milliampere (mA) accuracy. Its primary purpose is to help you compare the performance of different chargers and USB cables on the same device.

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For frequently asked questions, please visit: http://goo.gl/R8XgXX

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To use Ampere, simply launch the app and wait approximately 10 seconds for the measurement process to begin. The charging or discharging current will then be displayed.

The measured current is influenced by several factors, including:
- Charger type (USB, AC, Wireless)
- USB cable quality
- Phone model
- Background tasks
- Screen brightness
- Wi-Fi status
- gps status

While Ampere provides valuable insights, please remember that readings should not be considered scientifically precise. However, the relative measurements are reliable for comparing the performance of various chargers and USB cables on your specific device.

If the app consistently displays 0mA, try enabling the "Old measurement method" in the settings. This option forces the app to use an alternative measurement interface, if available on your device (particularly on Lollipop and later).

Known Issue: Some Samsung devices may not provide accurate measured values due to firmware limitations. These devices may only report the maximum possible charging current for the current USB cable/charger configuration (e.g., S5).

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How it works: Ampere measures the battery's charging/discharging current. When your phone is not connected to a charger, the app displays the discharging current (a negative value). When connected to a charger, the app displays the current supplied by the charger, with the remaining power being used to charge the battery.

For example, if your phone consumes 300mA without a charger (-300mA on the display) and you connect a 500mA charger, the battery will charge at a maximum of 200mA (200mA on the display).

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Technical Details: The displayed current is an average value calculated from 50 measurements, excluding the 10 highest and 10 lowest values. Fluctuations, instability, or zero readings may occur due to inconsistent values provided by the Android system. Variations in battery types and hardware across different manufacturers can also impact accuracy.

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Important Information about LiPo Batteries: LiPo batteries do not Draw maximum current throughout the entire charging cycle. The charging current decreases as the battery approaches full capaCity.

- Understanding LiPo charge stages: http://batteryuniversity.com/_img/content/ion1.jpg
- LiPo Charging Tutorial by Dave (EEVBlog): http://youtu.be/A6mKd5_-abk

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Phones/ROMS compatible with "Old measurement method" (enable and select the correct "Measurement interface"):
➤ HTC One M7 / M8
➤ LG G3

Phones/ROMS reported to be incompatible with this app:
➤ Galaxy Grand Prime - fortuna3gdtv
➤ Galaxy Note2 - t03g, t03gchn, t03gchnduos, t03gcmcc, t03gctc, t03gcuduos
➤ Galaxy S3 - d2att, d2spr, d2vmu
➤ Galaxy Tab4 7.0 - degas3g
➤ HTC Desire 510 - htc_a11ul8x26
➤ HTC One S (ville), X (endeavoru), XL (evita)
➤ HTC Sensation 4G - pyramid

If your phone is listed above, please do not leave a negative review. The issue is not with the app, but with your phone's lack of support for this type of measurement.

If the app does not work on your pre-Lollipop Android device, please consult the following XDA developer forum thread: http://goo.gl/pZqJg8. Please post your problem with screenshots in the XDA thread.

For further assistance, please refer to the FAQ: http://goo.gl/R8XgXX