Freescale Announces RFICs for GSM Wireless Markets

February 13, 2007 by Jeff Shepard

Freescale Semiconductor announced the release of what the company is describing as the industry’s first two-stage RF Integrated Circuits (RFICs) capable of delivering the 100W RF output power required for GSM and EDGE network base stations. Freescale claims that the devices are the highest power two-stage RFICs to be offered commercially.

When driven by Freescale’s MMG3005N general purpose amplifier (GPA), the MWE6IC9100N and MW7IC18100N RFICs are intended to form a comprehensive 100W power amplifier solution for wireless base stations operating at 900 and 1800MHz. The advantages are claimed to be significant for the GSM and EDGE market. Historically, the output power of two-stage RFICs has been limited to less than 30W, relegating their utility to driver and pre-driver stages. Previous designs required a separate high power transistor to achieve the 50 dB of gain and the 100W of output power typically required for GSM EDGE transmitters. Now, only a GPA and a single RFIC combine to meet this requirement.

The MWE6IC9100N is designed for both the 869 to 894MHz cellular and 920 to 960 MHz GSM bands. For GSM operation, the device is designed to deliver CW output power of at least 100W at 1-dB gain compression (P1dB) in 28 V Class AB bias conditions. Gain is 33.5 dB and power added efficiency is in excess of 52% over the intended operating range. Under a 28V drain bias and 50W average output power in an EDGE application, the MWE6IC9100N addresses the stringent linearity requirements with spectral regrowth of -63 dBc and -81 dBc at 400 kHz and 600kHz, respectively, with EVM of 2% rms.

The MW7IC18100N covers the 1805 to 1880 MHz and 1930 to 1990 MHz bands. It is designed to deliver P1dB RF output power of 100W CW with 30 dB of gain and power added efficiency of 48% over the intended operating range when running in a GSM environment at 28V. EDGE performance includes average power of 40W, spectral regrowth of -63 dBc (400kHz offset) and -80 dBc (600kHz offset), with EVM of 1.5%rms.

Housed in cost-effective over-molded plastic packaging, both RFICs are internally-matched and exhibit outstanding ruggedness. They have integral ESD protection, are RoHS compliant and can handle 200°C junction temperatures. They also include an integral quiescent current thermal tracking device that provides effective temperature compensation to keep current constant within 5% over a 115°C operating temperature range for all amplifier stages.

The RFICs are intended to help simplify power amplifier system designs by incorporating an automatic biasing function, which allows designers to set amplifier biases with minimal external circuitry. Additionally, the devices automatically compensate to set the desired drain quiescent current with a minimum amount of external control circuitry required.

The MWE6IC9100N is in full production and available now. The MW7IC18100N is sampling now with full production planned for March 2007. Validated RF models and full lineup demo boards using MMG3005N are available now for both products.