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The LTC554x family of downconverting mixers from Linear Technology offers high dynamic range and cover the 700-MH to 4-GHz wireless infrastructure frequency range. They also offer a 26-dBm input third-order intercept (IIP3) 9- to 10-dB noise, and 8-dB conversion gain for excellent dynamic range performance for main receivers and digital predistortion receivers, according to the company.

Furthermore, Linear says that the LTC554x family provides best-in-class capability to maintain a low noise figure in the presence of strong blocking interferers, as well as significantly enhance receiver sensitivity and robustness. Unlike other mixers in their class, these devices operate from a single 3.3-V supply without compromising performance while reducing power consumption by 34% compared to the closest competing solution, the company says.

The LTC554x family of downconverting mixers from Linear Technology is designed to satisfy the requirements of LTE cellular and WiMAX basestations as well as 3G CDMA, WCDMA, TD-SCDMA, UMTS, and GSM/EDGE platforms.

The LTC554x mixers are designed to satisfy the requirements of nascent fourth-generation Long-Term Evolution (LTE) cellular and WiMAX basestations as well as 3G CDMA, WCDMA, TD-SCDMA, UMTS, and GSM/EDGE platforms. Their robust performance also enhances other wireless systems such as point-to-point microwave systems, cellular repeaters, public safety radios, and military communication systems.

Additionally, the mixers pack an integrated IF amplifier, LO buffer, LO switch, and RF balun transformers. Each mixer’s RF input is single-ended, 50-Ω matched. Two single-ended LO inputs with high isolation are provided for frequency-hopping applications. Each LO input is also single-ended, always 50-Ω matched regardless of whether the mixer is active of powered down to avoid unlocking of the phase-locked loop (PLL). The LO input requires only 0-dBm drive level. All of these features facilitate a compact solution with minimal external components.

The mixers also have identical pinouts, so designers can share printed-circuit board (PCB) layouts across multiple platforms operating in different frequency bands. This helps users reduce total ownership costs and accelerates time-to-market. The pinouts are similar to common industry footprints and pinouts for ease of adoption while improving performance and reducing power consumption.

Drawing a supply current of 200 mA, the LTC554x devices have a power-down feature with turn-on and turn-off time of 2 µs and 3 µs, respectively. When disabled, the ICs consumer a maximum of 500 µA. They come in a 20-lead, 5- by 5-mm quad flat no-lead surface-mount package. Production will begin in November. Sampling now, production quantities will be available by February 2010. Pricing for the LTC5541 starts at $6.50 each.