# USB vs. HYBRID Power Mode

The connected source(host) device powers the T71 USB DAC and the source devices can be broadly categorized into two types:

* Desktop environments, such as PCs and laptops, where constant power is supplied.
* Devices like smartphones that are powered by a limited battery.

{% hint style="info" %}
Statistically, over 80% of users listen to music using their smartphones.
{% endhint %}

***

The T71 is equipped with a 1000mA battery and offers two power modes, as below, for use with smartphones.

### VBUS Mode

The T71 operates on external USB power from the source(host) device.

The connected VBUS Power Source supplies all the power required for the T71's operation, and the battery is not used at all.

{% hint style="info" %}
In most cases, VBUS mode is recommended.
{% endhint %}

### HYBRID Mode

The T71 operates on both external USB and the T71's battery power.

This mode automatically turns off the built-in charger and will not charge the battery.

When used with a smartphone, this mode helps prevent excessive battery consumption by the T71 from the smartphone.

{% hint style="warning" %}
For iPhones with a Lightning port, the current supplied to the connected accessory is limited to a maximum of 150mA. If the USB DAC connected consumes more than 150mA of current, the iPhone automatically disconnects the USB connection. For use with iPhones, HYBRID mode is recommended.
{% endhint %}

***

{% hint style="success" %}
There is no difference in sound quality between VBUS and HYBRID modes.
{% endhint %}


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