Transmitters that allow you to
display the voltage of the on-board network, so as not to accidentally completely discharge the battery. Or to indicate the corresponding parameter for older cars that do not have such a function.
The transmitter has a specialized
USB port for charging smartphones, tablets and other external devices.
Note that you can also charge external devices from conventional USB connectors; however, specialized ports provide higher power output, which can significantly reduce charging time. It is also worth mentioning that the specific purpose of such a connector can be different: in some models it works only as a power source, in others it can also be used to connect USB drives. Many FM transmitters have two USB ports — regular and charging; this allows you to simultaneously charge an external gadget and listen to music from a USB flash drive. And in modern devices, the old USB A form factor is supplemented by a modern
USB-C port.
The quick charge function, as the name suggests, allows you to significantly reduce the time spent on the procedure. This is achieved through increased current and/or voltage, as well as "smart" process control (at each stage, the current and voltage correspond to the optimal parameters). At the same time, the rechargeable gadget must also have a similar fast charging technology.