830MHz medium power amplifier principle circuit composed of RF2104

As shown in the figure, the principle circuit of the 830MHz medium-frequency amplifier composed of RF2104 is shown. The radio frequency signal (RF) is input from pin 5, and is amplified by the preamplifier and the final power amplifier and output from pin 12. There is a DC voltage at pin 5, so a DC-isolating coupling capacitor is added to pin 5, and a shunt inductor (10nH) is connected in parallel. The input impedance of pin 5 is 50Ω. The output pins 12 and 13 are connected inside the chip. Usually, pins 13 and 14 are connected together externally as signal output. The output is connected to a matching network to match the amplifier output impedance. The maximum output power can be obtained when the load impedance of this pin is 5 j0Ω. Pins 13 and 14 are connected together externally and also serve as the power supply terminal of the final power amplifier. Pin 8 is connected to the power control pin (PC). When this pin is connected to 0V and 3V, the gain can be controlled, thereby controlling the power; when the gain does not need to be controlled, this pin can be connected to a fixed voltage of 2.5~3V; when this pin is connected to a 2.5V voltage, the maximum current flowing into this pin is 1mA.