General description

The SA636 is a low-voltage high performance monolithic FM IF system with high-speed RSSI incorporating a mixer/oscillator, two limiting intermediate frequency amplifiers, quadrature detector, logarithmic Received Signal Strength Indicator (RSSI), voltage regulator, wideband data output and fast RSSI op amps. The SA636 is available in 20-lead SSOP (Shrink Small Outline Package) and HVQFN20 (quad flat package).

Features and benefits

■ Wideband data output (600 kHz minimum)

■ Fast RSSI rise and fall times

■ Low power consumption: 6.5 mA typical at 3 V

■ Mixer input to >500 MHz

■ Mixer conversion power gain of 11 dB at 240 MHz

■ Mixer noise figure of 12 dB at 240 MHz

■ XTAL oscillator effective to 150 MHz (LC oscillator to 1 GHz local oscillator can be

injected)

■ 92 dB of IF amp/limiter gain

■ 25 MHz limiter small signal bandwidth

■ Temperature compensated logarithmic Received Signal Strength Indicator (RSSI) with

a dynamic range in excess of 90 dB

■ RSSI output internal op amp

■ Internal op amps with rail-to-rail outputs

■ Low external component count; suitable for crystal/ceramic/LC filters

■ Excellent sensitivity: 0.54 μV into 50Ω matching network for 12 dB SINAD (Signal-to-Noise And Distortion ratio) for 1 kHz tone with RF at 240 MHz and IF at 10.7 MHz

■ 10.7 MHz filter matching (330 Ω)

■ Power-down mode (ICC = 200 μA)

■ ESD protection exceeds 2000 V HBM per JESD22-A114 and 1000 V CDM per JESD22-C101

■ Latch-up testing is done to JEDEC Standard JESD78 Class II, Level B

Applications

■ DECT (Digital European Cordless Telephone)

■ Digital cordless telephones

■ Digital cellular telephones

■ Portable high performance communications receivers

■ Single conversion VHF/UHF receivers

■ FSK and ASK data receivers

■ Wireless LANs