Table of Contents
What causes clipping in BJT?
The clipping levels of a single-stage amplifier are caused by over driving the transistor so that it either saturates or cuts off. Ideally, an amplifier should be designed so that it exhibits symmetrical clipping. That is, the amplifier should be able to put out positive and negative peak levels that are equal to each.
What causes clipping of an amplifier output signal?
Output clipping can be caused by exceeding the input common-mode voltage range (input headroom) or the input differential voltage range of the amplifier. Clipping can also occur when the output voltage range (output headroom) of the amplifier is exceeded.
Why do we go for cut off frequency in BJT amplifier?
Amplitude Distortion due to Incorrect Biasing If there is insufficient bias and the Q-point lies in the lower half of the load line, then the output waveform will look like the one on the right with the negative half of the output waveform “cut-off” or clipped.
How do amplifiers reduce distortion?
Using negative feedback to control the gain of the amplifier stages can also reduce amplitude distortion by ensuring that a signal level is not reached where the output waveform of one stage may drive a following stage into its saturation and/or cut off regions.
How do you calculate quiescent collector current?
The quiescent Base voltage (Vb) is determined by the potential divider network formed by the two resistors, R1, R2 and the power supply voltage Vcc as shown with the current flowing through both resistors. Then the total resistance RT will be equal to R1 + R2 giving the current as i = Vcc/RT.
What is frequency response of BJT?
The frequency response of an amplifier refers to the frequency range in which the amplifier will operate with negligible effects from capacitors and device internal capacitance. This range of frequencies can be called the mid-range. Also, cascading amplifiers limits the gain at high and low frequencies.
How do you mitigate clippings?
Avoiding clipping The simplest way to avoid clipping is to reduce the signal level. Alternatively the system can be improved to support higher signal level without clipping. Some audiophiles will use amplifiers that are rated for power outputs over twice the speaker’s ratings.