What is RF VGA?
About Variable Gain Amplifiers (RF VGA or DVGA) A device that utilizes digtial control is called a digital variable gain amplifier (DVGA).
What is LNA RF?
A low-noise amplifier (LNA) is an electronic amplifier that is used to amplify signals of very low strength, usually from an antenna where signals are barely recognizable and should be amplified without adding any noise, otherwise important information might be lost.
What is current gain in amplifier?
Mathematically, the gain of a current amplifier is the ratio between the magnitude of current flowing through its output terminals, to the magnitude of current of the input signal. It is denoted by the symbol Ai and because it is a ratio, it has no units.
What is the difference between LNA and PA?
The PA stands for power amplifier, in this case a RF or microwave amplifier used for transmission of a signal. LNA stands for low noise amplifier, normally used for high RF bands or microwave signals as a sensitive signal receiver. PAs and LNAs are not always combined. It depends on the application.
What is LNA gain?
Gain is the ratio of input to output power. For a single stage LNA, this is typically 15 dB. Typical GPS LNA’s use two or three gain blocks and yield 25 dB to 50 dB of gain depending on the user’s requirement.
What are variable gain amplifiers (VGAs)?
Qorvo’s variable gain amplifiers (VGAs) integrate high-performance amplifier solutions along with digital or analog gain control. Several of our VGAs integrate all of the RF matching and bias circuitry into a single package, providing a very compact solution and reducing PCB space. Integration offers PCB size reduction.
What is a variable gain amplifier for RF systems?
You can think of a variable gain amplifier for RF systems (RF VGA) as simply combining an amplifier (gain device) and an attenuator in the same package. A device that utilizes digtial control is called a digital variable gain amplifier (DVGA).
How do you control the output voltage of an inverting amplifier?
On the inverting amplifier a potentiometer is used to control manually the output voltage, replacing the standard feedback resistor. Build the following breadboard circuit for the voltage-controlled amplifier using transistors. Figure 5. Variable Gain Inverting Amplifier using potetiometer – breadboard circuit
How do you vary the gain of an op-amp?
Most operational amplifier or op-amp circuits have a fixed level of gain. However it is often useful to be able to vary the gain. This can be done simply by using a potentiometer on the output of a fixed gain op-amp circuit, but sometimes it may be more useful to vary the actual gain of the amplifier circuit itself.