Atmel Corp. has released a highly integrated high-performance RFIC for digital cordless phones operating at the license-free 5.8 GHz frequency band. Thanks to high integration, low number of external components and easy handling, the new devices will help to reduce manufacturing costs of cordless phones by about 25 percent, depending on the design. This solution also supports multihandset applications.

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Currently, the RF part of 5.8 GHz cordless phones is manufactured using discrete circuitry, involving more than 200 components and a large printed circuit board. Using the 5.8-GHz RF solution enables cordless phone designers to reduce the number of external components down to 80 and the board size by nearly 50 percent, claims Atmel. The supplier's reference boards demonstrate excellent performance in terms of sensitivity (-97 dBm) and power output (27 dBm), resulting in improved phone coverage externally at distances of more than 300 meters.

Most cordless phone manufacturers already have decided to offer high-end products with an increased number of features in the 5.8-GHz frequency range. A key benefit is the absence of interferences due to pagers; microwave oven; Bluetooth, WLAN etc., since this frequency band is not used for any other application than cordless phones.

On the base station side, Atmel's 5.8-GHz solution contains a 2.9-/2.4-GHz transceiver IC ATR2808, which is a single-chip device with integrated synthesizer and VCO including resonator, and the upconversion mixer ATR7039 as frequency doubler. The second harmonic is selected by a dielectric bandpass filter directly supplying the input of the 5.8-GHz power amplifier ATR7035 with an output power of 28 dBm. Both the ATR7035 and the ATR7039 are devices manufactured in Atmel's advanced SiGe technology, which requires only a single 3-V supply voltage. They feature a high output power of 11 dBm and require only a few external components. On the base station's receiving side, the solution includes a highly integrated 2.4-GHz SiGe LNA T7024 with a typical gain of 18 dB and a noise figure of typically 2.1 dB.

The dual-band 5.8 GHz RF for the handset receives at 5.8 GHz and transmits at 2.4 GHz. In the RF module's handset portion, the 5.8-GHz signal is downconverted by a versatile mixer, the ATR2809 alongside a fixed local oscillator of approximately 3.3 GHz generated by the VCO/PLL IC ATR2807. This VCO/PLL IC features an auxiliary voltage regulator on-chip (3.2 V-4.6 V) and a fast settling synthesizer. The resulting IF frequency in the range of 2.4 GHz is demodulated by the transceiver IC T2802. Its ramp-signal generator for power ramping and power control of external amplifiers makes this device suited to work in combination with the T7026, a highly efficient 2.4 GHz power amplifier with 26 dBm output power.

Samples are available now. Pricing for the entire set starts at $13 (10k). The following packages are available: ATR2807: QFN32, ATR2808: QFN48, ATR2809: QFN16, ATR7035: QFN16, ATR7039: QFN16, T2802: QFN48, T7024: SSOP20, T7026: QFN20.

Reference boards for the handset and the base station to speed up the design-in time are also available. Pricing is $2000.