LT5506EUF

Product Summary

The LT5506EUF is a Quadrature Demodulator. The LT5506EUF is a 40MHz to 500MHz monolithic integrated quadrature demodulator with variable gain amplifier (VGA), designed for low voltage operation. It supports standards that use a linear modulation format. The chip consists of a VGA, quadrature down-converting mixers and low pass noise filters. The LO port consists of a divide-by-two stage and LO buffers. The IC provides all building blocks for IF down-conversion to I and Q baseband signals with a single supply voltage of 1.8V to 5.25V. The VGA gain has a linear in-dB relationship to the control input voltage. Hard-clipping amplifiers at the mixer outputs reduce the recovery time from a signal overload condition. The low pass filters reduce the out-of-band noise and spurious frequency components. The cut-off frequency of the noise filters is approximately 8.8MHz. The external 2xLO frequency is required to be twice the IF input frequency for the mixers. The standby mode provides reduced supply current and fast transient response into the normal operating mode when the I/Q outputs are AC-coupled to a baseband chip. The applications of the LT5506EUF include IEEE802.11, High Speed Wireless LAN and Wireless Local Loop.

Parametrics

LT5506EUF absolute maximum ratings: (1)Supply Voltage: 5.5V; (2)Differential Voltage Between 2xLO+ and 2xLO–: 4V; (3)IF+, IF– : –500mV to 500mV; (4)IOUT+, IOUT–, QOUT+, QOUT–: VCC – 1.8V to VCC; (5)Operating Ambient Temperature (Note 2): –40℃ to 85℃; (6)Storage Temperature Range: –65℃ to 125℃; (7)Voltage on Any Pin Not to Exceed: –500mV to VCC + 500mV.

Features

LT5506EUF features: (1)Wide Range 1.8V to 5.25V Supply; (2)Frequency Range: 40MHz to 500MHz; (3)–4dB to 59dB Variable Power Gain; (4)THD < 0.12% (–58dBc) at 800mVP-P Differential Output Level; (5)8.8MHz I/Q Low pass Output Noise Filters; (6)IF Overload Detector; (7)Baseband I/Q Amplitude Imbalance: 0.2dB; (8)Baseband I/Q Phase Imbalance: 0.6°; (9)6.8dB Noise Figure at Max Gain; (10)Input IP3 at Low Gain: –0.5dBm; (11)Low Supply Current: 27mA; (12)Low Delay Shift Over Gain Control Range: 2ps/dB; (13)Outputs Biased Up While in Standby; (14)16-Lead QFN 4mm x 4mm Package with Exposed Pad.

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