Is lm4702 with one 5200 1943 pair stable with 18pf compensation cap?
R rhythmsandy Member Joined 2012 2013-09-15 5:07 am #1 2013-09-15 5:07 am #1 Is lm4702 with one 5200 1943 pair stable with 18pf compensation cap? ••• More options Share jackinnj Member Joined 2002 tech-diy.com 2013-09-15 5:16 am #2 2013-09-15 5:16 am #2 LM4702 is happier driving Darlingtons or Lateral MOSFETs -- read the data sheets and ap notes. ••• More options Share R routhun Member Joined 2005 2013-09-15 6:19 am #3 2013-09-15 6:19 am #3 You better check to make sure this amp is not oscillating at such lower values. I could not stabilize with less than 56pf with those transistors. ••• More options Share jackinnj Member Joined 2002 tech-diy.com 2013-09-15 1:36 pm #4 2013-09-15 1:36 pm #4 The LM4702 can't deliver enough current to drive 2SC5200 -- that's your first problem. ••• More options Share R rhythmsandy Member Joined 2012 2013-09-15 2:39 pm #5 2013-09-15 2:39 pm #5 I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys? ••• More options Share Show hidden low quality content Status This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button. Share: Facebook Twitter Reddit Pinterest Tumblr WhatsApp Email Share Link
jackinnj Member Joined 2002 tech-diy.com 2013-09-15 5:16 am #2 2013-09-15 5:16 am #2 LM4702 is happier driving Darlingtons or Lateral MOSFETs -- read the data sheets and ap notes. ••• More options Share R routhun Member Joined 2005 2013-09-15 6:19 am #3 2013-09-15 6:19 am #3 You better check to make sure this amp is not oscillating at such lower values. I could not stabilize with less than 56pf with those transistors. ••• More options Share jackinnj Member Joined 2002 tech-diy.com 2013-09-15 1:36 pm #4 2013-09-15 1:36 pm #4 The LM4702 can't deliver enough current to drive 2SC5200 -- that's your first problem. ••• More options Share R rhythmsandy Member Joined 2012 2013-09-15 2:39 pm #5 2013-09-15 2:39 pm #5 I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys? ••• More options Share Show hidden low quality content Status This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button. Share: Facebook Twitter Reddit Pinterest Tumblr WhatsApp Email Share Link
R routhun Member Joined 2005 2013-09-15 6:19 am #3 2013-09-15 6:19 am #3 You better check to make sure this amp is not oscillating at such lower values. I could not stabilize with less than 56pf with those transistors. ••• More options Share jackinnj Member Joined 2002 tech-diy.com 2013-09-15 1:36 pm #4 2013-09-15 1:36 pm #4 The LM4702 can't deliver enough current to drive 2SC5200 -- that's your first problem. ••• More options Share R rhythmsandy Member Joined 2012 2013-09-15 2:39 pm #5 2013-09-15 2:39 pm #5 I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys? ••• More options Share Show hidden low quality content Status This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button. Share: Facebook Twitter Reddit Pinterest Tumblr WhatsApp Email Share Link
You better check to make sure this amp is not oscillating at such lower values. I could not stabilize with less than 56pf with those transistors.
jackinnj Member Joined 2002 tech-diy.com 2013-09-15 1:36 pm #4 2013-09-15 1:36 pm #4 The LM4702 can't deliver enough current to drive 2SC5200 -- that's your first problem. ••• More options Share R rhythmsandy Member Joined 2012 2013-09-15 2:39 pm #5 2013-09-15 2:39 pm #5 I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys? ••• More options Share Show hidden low quality content Status This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
R rhythmsandy Member Joined 2012 2013-09-15 2:39 pm #5 2013-09-15 2:39 pm #5 I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys? ••• More options Share
I have tested it with 47pf as single pole and is very stable so im thinking of using 47pf for base compensation and 150pf as second cap for two pole compensation as its 3 times 47pf wat do u say guys?