The ADL5811 uses revolutionary new broadband, square wave limiting, local oscillator (LO) amplifiers to achieve an unprecedented radio frequency (RF) bandwidth of 700 MHz to 2800 MHz. Unlike conventional narrow-band sine wave LO amplifier solutions, this permits the LO to be applied either above or below the RF input over an extremely wide bandwidth. Because energy storage elements are not used, the dc current consumption also decreases with decreasing LO frequency.
The ADL5811 uses highly linear, doubly balanced, passive mixer cores along with integrated RF and LO balancing circuits to allow single-ended operation. The ADL5811 incorporates programmable RF baluns, allowing optimal performance over a 700 MHz to 2800 MHz RF input frequency. The balanced passive mixer arrangement provides outstanding LO-to-RF and LO-to-IF leakages, excellent RF-to-IF isolation, and excellent intermodulation performance over the full RF bandwidth.
The balanced mixer cores also provide extremely high input linearity, allowing the device to be used in demanding wideband applications where in-band blocking signals may otherwise result in the degradation of dynamic range. Blocker noise figure performance is comparable to narrow-band passive mixer designs. High linearity IF buffer amplifiers follow the passive mixer cores, yielding typical power conversion gains of 7.5 dB, and can be used with a wide range of output impedances. For low voltage applications, the ADL5811 is capable of operation at voltages down to 3.6 V with substantially reduced current. Two logic bits are provided to power down (<1.5 mA) the circuit when desired.
All features of the ADL5811 are controlled via a 3-wire serial port interface, resulting in optimum performance and minimum external components.
The ADL5811 is fabricated using a BiCMOS high performance IC process. The device is available in a 32-lead, 5mm × 5mm, LFCSP package and operates over a −40°C to +85°C temperature range. An evaluation board is also available.
Applications
- Multiband/multistandard cellular base station receivers
- Wideband radio link diversity downconverters
- Multimode cellular extenders and broadband receivers
