DESCRIPTION

The SA639 is a low-voltage high performance monolithic FM IF system with high-speed RSSI incorporating a mixer/oscillator, two wideband limiting intermediate frequency amplifiers, quadrature detector, logarithmic received signal strength indicator (RSSI), fast RSSI op amps, voltage regulator, wideband data output, post detection filter amplifier and data switch. The SA639 is available in 24-lead TSSOP (Thin shrink small outline package).

FEATURES

• VCC = 2.7 to 5.5V

• Low power consumption: 8.6mA typ at 3V

• Wideband data output (1MHz min.)

• Fast RSSI rise and fall times

• Mixer input to >500MHz

• Mixer conversion power gain of 9.2dB and noise figure of 11dB at

110MHz

• XTAL oscillator effective to 150MHz (L.C. oscillator to 1GHz local

oscillator can be injected)

• 92dB of IF Amp/Limiter power gain

• 25MHz limiter small signal bandwidth

• Temperature compensated logarithmic Received Signal Strength

Indicator (RSSI) with a dynamic range in excess of 80dB

• RSSI output internal op amp

• Post detection amplifier for filtering

• Programmable data switch

• Excellent sensitivity: 2.24µV into 50Ω matching network for 10dB

SNR (Signal to Noise Ratio) with RF at 110MHz and IF at 9.8MHz

• ESD hardened

• Power down mode

APPLICATIONS

• DECT (Digital European Cordless Telephone)

• FSK and ASK data receivers