Power amp speeds switch to EDR Bluetooth

Edited by the Electronicstalk editorial team Apr 25, 2006

A miniature power amplifier is optimised for both standard Bluetooth and enhanced datarate applications.

SiGe Semiconductor has expanded its series of RangeCharger integrated circuits with a miniature power amplifier optimised for both standard Bluetooth and enhanced datarate (EDR) applications.

The SE2425U power amplifier is based on a high-efficiency silicon-germanium architecture that allows EDR to be supported over longer distances when implemented in Bluetooth-capable cellular handsets, personal digital assistants (PDAs), wireless headsets, laptop computers and cordless telephones.

The new power amplifier is designed specifically to boost performance and reduce current consumption of devices compliant to both the Bluetooth v2.0 specification and EDR protocol.

The EDR protocol was developed by the Bluetooth Special Interest Group (SIG) to enable Bluetooth wireless connections with bandwidth of up to 3Mbit/s.

With a datarate that is three times faster than standard Bluetooth, EDR enables faster connections, simultaneous support of multiple Bluetooth links, and new higher bandwidth applications such as streaming audio.

EDR also extends battery life in portable devices, since the faster datarate will reduce the amount of time the Bluetooth radio is active.

EDR is expected to accelerate the acceptance of Bluetooth, as faster transmission and enhanced usability more closely match user expectations.

Manufacturers can optimise EDR performance by using the SE2425U to boost transmission range to distances of 100m.

Additional benefits include low current consumption, power saving modes and low quiescent current, which allows Class 1 and Class 2 operation to be supported in battery-powered mobile devices for the first time.

"The new SE2425U allows OEMs to deliver high datarate Bluetooth wireless capability unlike any other power amplifier on the market", said Andrew Parolin, Director of Wireless Data Products, SiGe Semiconductor.

"We are unique in delivering a solution that optimises performance in all modes of operation while still meeting the battery life and miniature size requirements driving this market".

The SE2425U solves a primary design challenge of new Bluetooth devices: ensuring optimal power output and efficiency in both standard and EDR operation.

Typically, power amplifiers are used in saturation during standard operation, and they are backed off for EDR mode.

This results in poor efficiency, and negatively impacts both transmission range and battery life.

The SE2425U solves this problem with digital mode control, which allows real-time selection of EDR or standard datarates, and boosts linear performance accordingly.

The SE2425U delivers +25dBm output power in standard rate GFSK mode and +19.5dBm output power in enhanced rate 8DPSK.

This allows systems based on the device to deliver an industry-leading +20dBm at the antenna in either mode, thereby ensuring reliable transmission over longer distances.

Using the SE2425U, manufacturers are able to achieve industry-leading performance without compromising battery life.

The device is based on an efficient silicon germanium architecture that ensures a low current draw of just 110mA at +20dBm power output, operating from a single 3.3V supply.

The device also features low quiescent current, allowing both Class 1 and Class 2 to be supported in the same design while maintaining battery life.

The current draw is reduced to 29mA in Class 2 output power levels.

The SE2425U is the first completely integrated power amplifier including input match, interstage matching and CMOS enable circuitry in a small 16-pin QFN package that measures just 3 x 3 x 0.5mm - the smallest footprint on the market.

The complete circuit only requires two external capacitors.

The integrated architecture reduces bill of materials and simplifies design, since no matching is required.

The SE2425U is available now.