This part is a kind of semiconductor called PSA4-5043.

Function of this product has Ultra Low Noise MMIC Amplifier.

Manufacturers : Mini-Circuits

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Ultra Low Noise MMIC Amplifier 50Ω 0.05 to 4 GHz PSA4-5043+ The Big Deal • Ultra Low Noise Figure, 0.75 dB • High IP3 and Po at low DC power consumption • May be used as a replacement for SPF5043Za,b • Class 1B HBM ESD rating (500V) CASE STYLE: MMM1362 Product Overview Mini-Circuits PSA4-5043+ is a E-PHEMT based Ultra-Low Noise MMIC Amplifier operating from 50 MHz to 4 GHz with a unique combination of low noise and high IP3 making this amplifier ideal for sensitive high dynamic range receiver applications. This design operates on +3 to +5V supply at only 33 mA at 3V and 56mA at +5V, is internally matched to 50 ohms and is supplied in a super small SC-70 (SOT-343) MSL 1 package. Key Features Feature Ultra Low Noise: 0.75 dB at 1 GHz 0.98 dB at 2 GHz Advantages [ ... ]

PSA4-5043 PDF Datasheet Download