SA620

The SA620 is a combined RF amplifier, VCO with tracking bandpass filter and mixer designed for high-performance low-power communication systems from 800-1200MHz. The low-noise preamplifier SA620 has a 1.6dB noise figure at 900MHz with 11.5dB gain and an IP3 intercept of -3dBm at the input. The gain is stabilized by on-chip compensation to vary
less than ±0.2dB over -40 to +85°C temperature range. The wide-dynamic-range mixer has an 9dB noise figure and IP3 of 6dBm at the input at 900MHz. An external LO can be used in place of the internal VCO for improved mixer input IP3 and a 3mA reduction in current. The SA620 incorporates a through-mode option so the RF amplifier SA620 can be disabled and replaced by an attenuator (S₂₁ = 7.5dB). This is useful for improving the overall dynamic range of the receiver when in an overload situation. The nominal current drawn from a single 3V supply is 10.4mA and 7.2mA in the thru-mode. Additionally, the VCO and Mixer can be powered down to further reduce the supply current to 1.2mA.