TI’s bqTESLA wireless charging development kit helps designers cut the cord on portable devices
By Alan Brandon
January 14, 2011
Between Bluetooth, Wi-Fi, and the latest-gen cell phone networks, we hardly ever have to plug anything into our mobile devices these days. That is, until the batteries die. Then, we’re rooting through a rat’s nest of USB cables and adapters trying to find the right wall wart and a plug that fits the charging port. Clearly wireless charging’s day has arrived, and Texas Instruments has released the industry’s first Qi-certified wireless power development kit. The bqTESLA kit is meant to help design engineers integrate wireless power technology into devices such as smartphones, digital cameras, and MP3 players.
Wireless power uses near-field magnetic induction to transfer power from a charging base station to a portable device (an alternate technology from Fujitsu uses magnetic resonance). With magnetic induction, a transmitter coil in the charging pad sends power over distances of a few centimeters to a receiver coil embedded in the device. In the charging base station, a power conversion unit converts electrical power to a wireless power signal. At the receiver, the power pickup unit converts the wireless power signal back to electrical power to charge the device’s battery. The transmitter and receiver communicate with each other to control the charging process. A base station can have more than one transmitter to charge more than one device.
Several wireless power solutions are on the market, such as the PowerDisc and the Powermat. However, because most portable devices do not have built-in wireless power receivers, these systems require proprietary adapters for charging. The Wireless Power Consortium (WPC) has defined the Qi specification to promote standardization among wireless power systems.
The Qi standard (pronounced “chee” and taken from the Chinese concept of “vital energy”) defines the interoperability between wireless power transmitters and power receivers. The Qi low-power standard provides up to 5 Watts for wireless power receivers, which meets the needs of most portable consumer devices that use USB charging. Under the WPC standard, Qi-compliant devices will work with any Qi-compliant chargers.
With the bqTESLA development kit, which TI announced at last year’s CES show, TI aims to help designers integrate Qi-compliant wireless power technology into portable consumer electronic devices as well as infrastructure applications such as furniture and cars. The TI bqTESLA development kit is now available, and includes a single-channel transmitter, a direct-charge receiver, and associated magnetics for applications that require 5 Watts of power or less. TI says no additional software development is required to implement the kit.
The main components of the TI bqTESLA development kit include:
The TI bqTESLA development kit is in production and available now at US$500. The individual components of the kit are also available for purchase in production quantities. Check Texas Instruments for more information.