Junus2012
Advanced Member level 5
Dear friends,
In the Jakob book he discussed about selecting the suitable value of the overdrive voltage of the transistors in the operational amplifier. for long channel he is using Vov = 250 mV (VDD= 5V).
My question how the overdrive voltage affect the speed of the operational amplifier ? consider please for example GBW = gm1,2/CL. in this equation only the input differential transistors are concinerned, and I can say yes higher overdrive voltage leads to higher gm1,2 and thus increases the gain. but what about other transistors? they are not included in the formula of GBW so why should they follow this value of overdrive voltage ?
Thank you in advance
In the Jakob book he discussed about selecting the suitable value of the overdrive voltage of the transistors in the operational amplifier. for long channel he is using Vov = 250 mV (VDD= 5V).
My question how the overdrive voltage affect the speed of the operational amplifier ? consider please for example GBW = gm1,2/CL. in this equation only the input differential transistors are concinerned, and I can say yes higher overdrive voltage leads to higher gm1,2 and thus increases the gain. but what about other transistors? they are not included in the formula of GBW so why should they follow this value of overdrive voltage ?
Thank you in advance