For low closed loop gain and high band width frequency compensation is used in op-amp 

There are two types of frequency compensation techniques they are:

  1. Internal frequency compensation technique.
  2. External frequency compensation technique.

Internal Frequency Compensation Technique :

  • It makes use of internal components for compensation.
  • Usually used in instrumentation amplifiers. 
  • Also called as internally compensated op-amp.
  • IC741 contains capacitance C_1 = 30pf which internally shunts off signal current and thus reduces available out put signal at higher frequency.
  • The internal capacitance C1= 30pf the compensating  element which causes open loop-gain to roll off at -20dB/decade rate and gives a stable circuit.
  • Bandwidth product of op-amp is 1mHz and if IC741 is wired for a closed loop gain of 104/80dB then its bandwidth is 100hz for a gain of 102 bandwidth.  The bandwidth increase to 10KHz with gain one making bandwidth 1Mhz.
 

External Frequency Compensation Technique :

These circuit fuse external frequency components to give low closed loop gain. The two common methods are:
  • Dominant pole compensation.
  • Pole zero compensation. 
 

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