HdrChopper
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hi,
Set Vb1 to Vonp and Vb2 to Vonn, where Vonp and Vonn are the input CM levels at which PMOS and NMOS diff pairs turn on respectively. If you do so then,
for vicm < vonn , IM1,2 = 0. thus IM5 = 2IR2 and IM8=0 (since M3,4 sources turn M8 off) for vicm > vonp, IM3,4 = 0, thus IM8 = 2IR1 and IM5=0 (since M1,2 sources turn M5 off)
for vonn < vicm < vonp, both IM8 and IM5 are OFF; otherwise, since the current loop is positive, adaptive bias circuit would not be controlled. In this case IM1,2 = 2IR2 and IM3,4 = 2IR1
Hope this helps Tosei
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