> For the complete documentation index, see [llms.txt](https://qudelix.gitbook.io/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://qudelix.gitbook.io/home/5k/power-management/power-management.md).

# Power Management

### Battery Bypass

As shown in the image below, when a USB is connected, the 5K is designed to receive power directly from the USB, not the battery. Out of the 5V 500mA provided by a typical PC USB port, 200mA is used for battery charging, while the remaining 300mA is used for the 5 K's operation.

<figure><img src="https://3332347321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F6eUmiJ4Hi4Cv2aUhWNRV%2Fuploads%2Ftlj5KcgxbhkqlL3C6wc9%2Fimage.png?alt=media&amp;token=c49ed167-4557-4216-9547-d10de94e9190" alt=""><figcaption><p>Qudelix-5K Power Management</p></figcaption></figure>

This design is crucial in maximizing the battery's lifespan. If the system continues using battery power while charging, the lifespan will significantly shorten.

{% hint style="info" %}
The built-in battery is not used when using the 5K as a USB DAC, and the entire system operates solely on USB power.
{% endhint %}

{% hint style="info" %}
Even without the battery, the system operates well when connected to USB power.
{% endhint %}

***

### Charging Complete

Once charging is complete, the internal charging circuit cuts the current to the battery, and the battery enters a state of free discharge with all connections cut off.

<figure><img src="https://3332347321-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F6eUmiJ4Hi4Cv2aUhWNRV%2Fuploads%2FpV722zGZyFMDeohJwk3S%2Fimage.png?alt=media&amp;token=9aaff481-1be6-4e08-b813-8efd50fbb279" alt=""><figcaption><p>Qudelix-5K Charging</p></figcaption></figure>

{% hint style="success" %}
Battery lifespan and device stability are not affected even if the 5K is always connected to a charger or PC USB port.
{% endhint %}