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raja.cedt Senior Fellow Offline Posts: 1516 Germany	Maneatis partial-swing delay cell. Jul 18^th, 2011, 12:24am hello, i have doubt regarding this delay cell. I know that one transistor in this pmos load has to be in triode region, because then only it will linear V-I characteristics. But if you see the replica bias i think because of the bias both both transistors in saturation region. Can any one please clarify this? Thanks.
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loose-electron Senior Fellow Offline Best Design Tool = Capable Designers Posts: 1638 San Diego California	Re: Maneatis partial-swing delay cell. Reply #1 - Jul 18^th, 2011, 2:29pm I have used the Maneatis delay cell in ring oscillators many times, but I did a redesign of the bias system
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neoflash Community Fellow Offline Mixed-Signal Designer Posts: 397	Re: Maneatis partial-swing delay cell. Reply #2 - Sep 6^th, 2011, 5:37pm loose-electron wrote on Jul 18^th, 2011, 2:29pm: I have used the Maneatis delay cell in ring oscillators many times, but I did a redesign of the bias system one thing I noticed is that anything I touched in its design will trigger a chain effect. The only exception is the charge pump.
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rajkumar palwai

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Posts: 46
Sunnyvale, California

Re: Maneatis partial-swing delay cell.
Reply #3 - Sep 29^th, 2011, 10:18am

Hi Raja,
You can understand maneatis cell in terms of current. Please see the attached figure. The figure plots the different current components of a maneatis cell w.r.to voltage across it.

The currnet through the �current source transistor �is shown in red color. The current thru diode connected is shown in blue curve. The average current (Itotal*0.5) is shown in black color. I have shown Itotal*0.5 current rather than Itotal, since it shows nicely how averaging is happening in the cell. Current will become some kind of linear across the voltage range and hence the cell acts as a linear resistor.

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rajkumar palwai Community Member Offline Posts: 46 Sunnyvale, California	Re: Maneatis partial-swing delay cell. Reply #4 - Sep 29^th, 2011, 10:20am Forgot to add the figure
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rajkumar palwai Community Member Offline Posts: 46 Sunnyvale, California	Re: Maneatis partial-swing delay cell. Reply #5 - Sep 29^th, 2011, 10:23am Hence the cell acts as a linear resistor only till the voltage where the cross over happens between two currents.
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