15dB gain differential amplifier: linearity, low noise, 100 kHz – 1.4 GHz
In addition to its signal-to-noise perforamance at high frequencies, it maintains its dynamic range performance even at lower frequencies, as its advanced SiGe bipolar design exhibits significantly lower 1/f noise frequency corner than that of GaAs or pHEMT FET based amplifiers. Hence its noise figure rises to only 6.6 dB at 100 kHz, compared to more than 20 dB for other amplifiers. The LTC6432-15 effectively extends the useful bandwidth and dynamic range performance for many applications that process low frequency signals and improves stability over temperature, power supply ranges and from device to device compared to GaAs and pHEMT amplifiers.
The amplifier’s high dynamic range and extended bandwidth to low frequencies broaden its usefulness and improve performance in a wide range of amplifier applications including high sample rate A/D converter drivers, cable network amplifiers, broadband signal source conditioning, radar receiver IF amplifiers, software defined radio, VHF/UHF broadcast radios and RF test instruments.
Its differential inputs and outputs are internally 100Ω terminated. Its inputs are matched from 100 kHz to 1.4 GHz, with better than 10 dB return loss over the full bandwidth. The output is also matched from 100 kHz to 1 GHz. The amplifier needs only DC blocking capacitors at its inputs and outputs, two chokes for proper biasing, plus one feedback capacitor per output to extend its excellent gain flatness to low frequencies.
The LTC6432-15 operates from a single 5V supply. It draws a nominal 166 mA supply current. The device is specified for operation over a case temperature range from –40°C to 85°C. The LTC6432-15 is available in a 4 x 4 mm plastic QFN package in two grades: a B-grade with all typical parametric performance at $3.69 and a higher performance A-grade with tested and guaranteed specifications at $6.44 (both 1000).
ADI/Linear Technology; www.linear.com/product/LTC6432-15
