Semtech Launches Industry’s First Multi-Channel, Differential Output Wideband LNA with Programmable Gain

Semtech Corp. (Nasdaq: SMTC), a leading supplier of analog and mixed-signal semiconductors, today announced the SX1701A / SX1701B / SX1701 family of highly linear wideband low noise amplifiers (LNAs) with differential outputs.  The devices are ideally suited for such applications as satellite and terrestrial TV set top boxes (STBs), RF active splitters and other active balun applications.

These wideband LNAs offer excellent RF performance and provide differential outputs compatible with current STB front-end tuner devices.  The SX1701 platform has a differential output architecture that eliminates the need for PCB baluns, and requires a minimal number of external components, thus saving board space and cost. SX1701 devices are offered in 1-, 2- and 3-channel versions with each active channel having independently selectable gain of +6dB, +12dB and +18dB, ideal for a wide dynamic range of input RF signals.  These devices provide LNA functionality to drive the main tuner, PIP tuner, and DVR tuner in STB applications as well as easy implementation of loop-thru architectures. 

The SX1701 family matches a 75-Ohm single-ended source to a 100-Ohm differential load while dissipating only 130mA (typ) of power per enabled channel.  The SX1701 devices provide a flat response from 40MHz to 2.5GHz ideal for terrestrial and satellite STB applications.  Each channel provides excellent RF performance and linearity offering OIP3 of 22dBm, OIP2 of 53dBm, and an output P1dB of +13dBm. With Input Return Loss of 15dB @2GHz and Output Return Loss of 20dB @2GHz, no external matching networks or bias inductors are required to deliver this performance, unlike competing devices.

“The wide linearity of this part is ideal for simplifying the design of next-generation multi-channel set top boxes that put a premium on flexible signal acquisition,” said Sam Massih, Product Line Manager, Consumer Analog Products for Semtech.  “The extreme linearity of this part is a significant advance, but when this is combined with the multi-channel differential output, it makes this platform a true industry breakthrough ideal for next generation silicon tuners.”

The SX1701A / SX1701B / SX1701 devices provide significant board space and BOM cost savings when either a differential LNA output or a multi-channel LNA architecture is required. These devices are available in a lead-free 4mm x 4mm 16-QFN package and operate over a temperature range of -40°C to +85°C.

KEY FEATURES OF THE SX1701 LNA FAMILY

• SX1701A has one channel;
• SX1701B has two channels;
• SX1701 has three channels
• Flat response from 40MHz to 2.5GHz
• OIP3 of 22dBm
• OIP2 of 53dBm
• Output P1dB of +13dBm
• Input Return Loss of 15dB @2GHz
• Output Return Loss of 20dB @2GH

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