The ADA4961 is a high performance BiCMOS RF differential amplifier optimized for driving heavy loads out to 1.5 GHz and beyond. It achieves -90 dBc IMD3 performance at 500 MHz and -87 dBc at 1.5 GHz. The device also exhibits very low output noise (6.8 nv/√hz). Together, these performance numbers result in an SFDR of 133 dB/Hz at 1.5 GHz and set a new benchmark for dynamic range for the power consumed. This RF performance now allows GHz converters to achieve their optimum performance with minimal limitations of the driver amplifier or constraints on overall power that typically result from GaAs amplifiers. This product can easily drive 10 to 16 bit HS converters. In addition, for many receiver applications, anti-alias filter (AAF) designs may be simplified or is not required.
The ADA4961 has an internal differential input impedance of 100 Ω and a differential dynamic output impedance of 50 Ω, eliminating the need for external termination resistors. The digital adjustability provides for 1 dB resolution, thus optimizing SNR for input levels spanning 21 dB.
Again, the ADA4961 is optimized for wideband, low distortion performance at frequencies up to and beyond 1.5 GHz. These attributes, together with its wide gain adjustment and relatively low power, will make it the amplifier of choice for many high speed applications. This includes IF, RF and broadband applications where dynamic range at very high frequencies is critical.
The ADA4961 is ideally suited for driving not only ADCs, but also mixers, pin diode attenuators, SAW filters, and multi-element discrete devices. It is available in a 4 mm ×4 mm, 24-lead LFCSP package, and operates over a temperature range of −40°C to +85°C.