The USB (Universal Serial Bus) is a standard that defines the cables, connectors and used a bus to connect, communicate, computers, peripherals and electronic devices protocols Transmission Rates Low speed (USB 1.0). Transfer rate up to 1.5 Mbit/s (188 kB/s) used in keyboard, mouse ... transfer rate up to 12 Mbit/s (1.5 MB/s) High Speed ??(USB 2.0): Rate transferencia up to 480 Mbit/s (60 MB/s) SuperSpeed ??(USB 3.0) transfer rate up to 4.8 Gbit/s (600 MB/s) Connector Types 1 - USB type A (4 pin) 2. - USB type B (4 pin) 3 - Mini A (5-pin) 4 - Mini B (5-pin) 5 - Micro A (5-pin) 6 - Micro B (5-pin)

or horizontal. The micro USB with five pins, which pins identification (ID) Micro AB USB connectors special work. AB connectors with pin ID can allow the device to function as a connector A or B to standard USB technology. This gives the new smart phones and other devices the option to act as either a single storage device or as provi

The mini USB connectors are smaller than their standard counterparts and have USB fifth pin. The fifth pin is known as the pin ID and is typically not used in mini USB connectors. It was designed to allow later improved USB technology. The mini USB connectors have a cycle life of at least 5000 connections and disconnections, which accommodates the mobile nature of the devices that are designed to interact. The standard USB connectors are generally used with devices that are stationary and not disconnected often.

USB 3.0 is the second major revision of the standard Universal Serial Bus (USB) connectivity for computing. USB 3.0 has transmission speeds of up to 5 Gbit/s, which is 10 times faster than USB 2.0 (480 Mbit/s). Connector Types 1 - USB type A plug 2 - 3 USB type A female - USB type B 4 - Micro USB B

USB-C reversible USB version called USB cables USB Type C Type C or USB reversible. The important thing is this type of USB is that it has top and bottom. So you may save the blows that are given involuntarily to connect the connector upside down. It is also characterized in that when connected will make an audible "click". The USB-C or reversible USB cables can reach 10 Gbps and support USB 3.0, 3.1Use is estimated up to 10,000 applications and has some measures 8.4mm x 2.6mm is also compatible with USB 3.1 and USB indicate creators

VDC would be the abbreviation for Volt Direct Current which translated would volts direct current. The idea of ??this type is unidirectional current to the load. Direct current is normally produced by batteries, thermocouples, solar cells and a dynamo electric machine type. The direct current can flow in conductors such as wires, but may also flow through semiconductors, insulators ... In the image: 1 - current per pulse 2 - Direct Current (DC) 3 - Alternating Current (AC) 4 - Variable Current

The battery bank or Power Bank is an ideal solution if you are running out of battery on your device when you really need it.
It's charged using a miniUSB or microUSB cable directly connected to a power source or USB port (PC or MAC).

Its operation is very simple, you only need to connect the battery bank to your smartphone, tablet, MP3, Ipod, etc. and automatically will start charging.

The provided charge to the device depends on the capacity in mAh of the battery bank, usually can perform a full charge of a device and depending on the capacity of the power bank, it can do it a few times.

To calculate the times you can charge your device simply divide the capacity of powerbank between the battery capacity of the device.

Example:
If the battery bank is 7.200mAh i your device is an Apple iPhone, Samsung Galaxy or similar with 1.800mA battery, you can charge up to 4 times without going through the plug.

The charging time of your device using a powerbank is very similar to the charging time using the original charger.

Ideal for long trips, meetings, campsites, etc.

When calculating the life of a battery it will be necessary to know the number of charge cycles that can be performed until the battery does not begin to lose its capacity.
Depending on the type of battery these charging cycles can vary, the most common being the mobile batteries, manufactured Li-Ion or Li-Po, which have a duration of between 300 and 500 charging cycles according to model and manufacturer.
Once thisE limit we will notice how the battery loses duration of operation, arriving to lose up to 25% of its capacity of load.
At this point it will be necessary to evaluate a battery change.
It should be noted that usage and charging habits can significantly affect battery life. For example, factors such as heat, charge the battery several times a day without it is almost exhausted, etc. Will be affectedits duration.
Therefore, to get the most out of the battery we must know when a full charge cycle is performed, and try to avoid misuse of charge, to increase its useful life.
A charging cycle is considered when the battery has been discharged or its 100% charge has been used.
The manufacturers advise that the charge is never made below the 58% battery, since the battery voltage would not fall so lowTo, so you could end up winning up to 4000 charge cycles.
Tips to increase the life of a battery.

• Avoid extreme heat or cold or very long applications of the device.
• Charge the battery as often as you can.
• Fully discharge the battery from time to time.
• Do not let the battery run out completely before charging.

Below is a table with theDifferent voltages (V), charge cycles (C) and battery percentage (B).