Linear Technology Corp. (LTC, Milpitas, CA) introduced its new LT5546 monolithic, high-performance IF quadrature demodulator, which operates with a single supply voltage as low as 1.8V, making it suitable for portable applications. The LT5546 has applications in GPS receivers, wireless local loop, satellite IF receivers, and mobile wireless data receivers.
The device accepts an intermediate frequency input signal from 40MHz to 500MHz, and incorporates a precision quadrature phase-shifter for accurate I/Q demodulation, and a low-distortion variable gain amplifier with a log-linear gain control range from -7dB to 56dB. The demodulated I/Q baseband signals pass through on-chip, 17MHz, low-pass, noise-reduction filters in the LT5546, reducing the need for external filtering. Moreover, the LT5546 includes an on-chip, signal power detector with a detection range of -30dBm to +8dBm to assist in high-signal level detection and corresponding gain adjustment.
The LTC5546 is offered in a 4mm x 4mm, 16-lead, plastic QFN, surface-mount package for a small PC board footprint. Pricing starts at $3.35 each in 1,000-piece quantities.
