Hi,
Do you agree that the Type 2b Error Amplifier is a waste of time in SMPS feedback compensation and should be done away with?
Its a fact that any feedback compensation that can be obtained with a Type 2b Error amplifier, can be improved on with a Type 2, Type 2a, or Type 3 Error amplifier.
The Type 2b offers no phase boost whatsoever, and clamps the gain which often isnt necessary, and the same gain (at whatever frequency) can be achieved with Type 2,2a or 3 anyway.
The only single use for a Type 2b, is where a low value resistor is used in parallel with the feedback cap, to prevent the error amplifier from saturating (to prevent integrator windup) ...however, this gives large DC offset error, and is simply not necessary in virtually all SMPS applications....if not all of them.