Mar 23, 2005 #1 I incol Full Member level 2 Joined Jan 18, 2005 Messages 143 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,296 Activity points 1,077 Vx=Vbe=0.65v,so Vin of opamp is 0.65v,then M1 will cuteoff for Vth=0.712v.Vbe can't be easily changed,how can i do?
Vx=Vbe=0.65v,so Vin of opamp is 0.65v,then M1 will cuteoff for Vth=0.712v.Vbe can't be easily changed,how can i do?
Mar 23, 2005 #2 H Hughes Advanced Member level 3 Joined Jun 10, 2003 Messages 715 Helped 113 Reputation 226 Reaction score 27 Trophy points 1,298 Activity points 5,984 You may use pmosfets as input transistor of the amplifier.
Mar 23, 2005 #3 M mike_bihan Full Member level 3 Joined Mar 21, 2002 Messages 182 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,296 Activity points 1,531 see my answer is analog circuit board.
Mar 28, 2005 #4 K kanbin　 Newbie level 3 Joined Feb 14, 2005 Messages 3 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 20 You can use 2 Bipolar (pnp) cascade transistor.