News

16 March 2009

 

Skyworks unveils FEMs with integrated power control scheme for quad-band handsets

Skyworks Solutions Inc of Woburn, MA, USA has launched a suite of highly integrated GSM, GPRS and EDGE front-end modules (FEM) with a small footprint and a unique power control scheme (based on a coupler detector) that greatly enhances the total radiated power (TRP) performance for quad-band cellular handsets. Different FEMs in the new family support the 2.5G and 3G platforms of baseband suppliers Broadcom, Infineon and MediaTek.

“Our complete transmission-to-antenna solution with integrated electrostatic discharge network is the perfect combination for today’s mobile handset manufacturers as they look to reduce bill-of-materials and printed circuit board footprint,” claims Thomas Richter, director of product marketing for front-end solutions.

The SKY77527 (8mm x 6mm x 1.12mm) – optimized for Infineon’s reference designs – and the SKY77528 (8mm x 6mm x 1.1mm) – supporting Broadcom’s platform – consist of a GSM850/900 and DCS1800/PCS1900 PA block, impedance-matching circuitry for 50 ohm input and output impedances, a multi-function power amplifier (PA) control (MFC) block, low-pass harmonic rejection filters, and a single-pole six-throw (SP6T) antenna transmit/receive (T/R) switch.

The MFC in the SKY77527 provides ‘pin-out’ for interoperation with an external power control loop. The external circuit uses the linear detector output to provide closed-loop power control in EDGE and gaussian minimum shift keying (GMSK) modes of operation. With an integrated saturation, detection and correction circuit, the SKY77528 also improves phone reliability with output radio frequency spectrum (ORFS) performance in voltage standing wave radio (VSWR) and low-battery condition.

The SKY77529 (7.5mm x 7mm x 1.1mm) – optimized for Infineon's reference designs – consists of a GSM850/900 PA block and a DCS1800/PCS1900 PA block, a printed directional coupler for each block, impedance-matching circuitry for 50 ohm input and output impedances, an MFC block, low-pass harmonic rejection filters, and a SP8T antenna T/R switch. The FEM, with an antenna that connects to any one of two reception (Rx) or four wideband code division multiple access (WCDMA) Rx/Tx ports, incorporates full support for a serial peripheral interface (SPI) bus function.

The SPI controller, which offers convenient digital control, accepts SPI telegrams with data fields that support PA and switchplexer-related functions. All FEM operating modes and switch states shall be determined by the SPI telegram. The MFC provides pin-out for interoperation with a specified transceiver that will establish a closed-loop power control mechanism. The external circuit uses the linear detector output to set a fixed bias point for 8PSK (EDGE) mode and a variable bias point for GMSK (GSM) mode, which allows easy-to-implement timing and calibration.

Finally, the SKY77546 (7mm x 6mm x 1.0mm) consists of an extended global system for mobile communications (EGSM900) PA block and a DCS1800 PA block, impedance-matching circuitry for 50 ohm inputs and outputs, a multi-function PA control block, low-pass harmonic rejection filter, and a Tx/Rx antenna switch. Supporting MediaTek’s low-cost EDGE platform, the module contains a diplexer filter which provides what are claimed to be excellent harmonics and electrostatic discharge (ESD) performance.

The SKY77527 and SKY77528 are already in volume production, while the SKY77529 is sampling now, and the SKY77546 will sample in second-quarter 2009.

See related items:

Skyworks launches LTE power amplifiers and front-end modules

Skyworks’ FEMs and PAs support Samsung’s latest GPRS, EDGE and 3G handsets

Search: Skyworks FEMs

Visit: www.skyworksinc.com