Recent advances in integrated RF circuit technology have allowed the design of easy to use RF blocks with single-ended RF input to differential IF output. The Analog Devices ADL5355 mixer is an example of a device which mixes a single ended RF input into a differential IF output. It allows for the inherent differential advantage to be maintained in a stubborn single-ended world. The ADL5355 block diagram shows that all three internal mixer ports are differential. For ease of use, the RF and LO ports are connected to the outside world using transformers, allowing for a single-ended interface. By contrast, the IF output port, which includes a driver amplifier is differential, with an output impedance of 200 ohms, to facilitate connection to a differential SAW filter. The integration of the LO and RF baluns (balanced to unbalanced transformers) limits the operating frequency range of the device, requiring a family of devices specified for operation across the cellular frequency ranges. As a result, the input frequency range of this device is limited to 1200MHz to 2500MHz with a low-side LO; that is, an LO frequency which is always less than the RF frequency.