A question about Charge pump

[holddreams]

In the attachment,
For transistor MD2 and MS2,

1)which node is the source?

2)How to connect the substrate of MD2 and MS2?

Thanks.

 

[Fom]

which node is the source?

Any. MOS transistor has symmetric structure.

How to connect the substrate of MD2 and MS2?

All of them NMOS transistors. Substrate is connected to the ground.

 

[holddreams]

Thank you.I got it.

If we use PMOS instead of Nmos,How to connect the Pmos substrate ?Using floating Nwell?

Any idea?

 

[ycj]

Thank you.I got it.

If we use PMOS instead of Nmos,How to connect the Pmos substrate ?Using floating Nwell?

Any idea?

As far as I known, there are at least 3 solutions:
1. Floating well, as you mentioned.
2. Dynamic substrate connection switching: At least 2 methods. Please refer to
a. Pierre Favrat..et al, "A High-Efficiency CMOS Voltage Doubler", JSSC V-33, No.3, Mar. 1998, p410~.
b. Jongshin Shin..et al, "A New Charge Pump Without Degradation in Threshold Voltage Due to Body Effect", JSSC V-35, No.8, Aug. 2000, p.1227~.
3. Tie to highest voltage: Please refer to
B. Robert Gregoire, "A Compact Switched-Capacitor Regulated Charge Pump Power Supply", JSSC V-41, No.8, Aug. 2006, p1944~.

 

[xiongshoufen]

good