Good Evening sir This videos are helping for VLSI stream students,staff and scholar in the filed of VLSI. keep going on making videos sir its is very helpful sir Thank You sir
Hello Mudasir, My name is Rahul and I am pursuing my masters in Nanoelectronic systems from Technische Universität Dresden, Germany. Currently I have been allocated 1 academic project : Design of DC-DC Buck Converter in 28nm CMOS Technology. In this work, an integrated switching circuit with an external inductor needs to be designed with converts a 3.7V battery voltage to output levels from 0.5V to 1.0V at loads between 10μW and 100μW. The conversion efficiency should be analyzed with focus on the properties (stray inductance, ohmic resistance, magnetic core loss, etc.) of the external inductor. Actually the milestone for this project is : (a) Schematic design and optimization of the integrated switching circuits in a 28nm CMOS technology and co-simulation with the Verilog description of the digital control loop. (b) Sizing and analysis of of the external inductor to maximize conversion efficiency within overall application constraints. I am completely new to Cadence Virtuoso framework. Can you please help me how to approach this project ? Any possible DC-DC Buck Converter schematic diagram. I would be grateful if could help me in this regard. Appreciate your help. Thanks and regards, Rahul Das
Hello Rahul, As per the schematic of dc-dc converter goes in cadence, we use the general procedure by taking different instances from the foundry Library. However, it is advised first to go with the analogLib instances (for inductor and capacitor). The dc-dc converter has four major components; 1) Inductor. which besides being part of LPF also stores energy and reduces the power loss in circuit. 2) Capacitor, used at the load for overshoot control. 3) Power Stage and Switch Controller. The stability of the feedback loop involved should be ensured. Switch Controller is controlled by signal (Pulse, triangular, PWM). This signal is generated using Verilog. So you have to use Verilog for designing switching circuits. I would suggest you first go through some literature related to LDOs and then start your DC-DC and a brief overview of poles and zeros in systems, how to locate pole and zeros in circuit. Learn how to find the transfer functions of a circuit. Finally, Specify which parameter you want to target, like power consumption, stability at low loads, load/line regulations PSR etc. I will upload a tutorial soon about the Verilog in Cadence. Happy to help.
Hello Mudasir, Thank you very much for your kind response and detailed information. Do I need to code in Verilog-AMS for designing switching circuits ? Power consumption and Maximization of conversion efficiency are the target parameters. It would be really helpful if could share your email ID so that I can communicate with you regarding any help in this direction. Also do i need to design power stage of DC-DC Buck converter at schematic level ? waiting for your kind acknowledgement so that at least in the upcoming weeks I can come up with the schematic design of dc-dc converter. Thanks and regards, Rahul
I guess you are using the latest version (>IC615). After dc simulation and annotating dc operating points. There is a wrench like symbol (picture) in the toolbar section of the schematic window (probably in the last row at the end). Click on that you can display these parameters.
Good Evening sir
This videos are helping for VLSI stream students,staff and scholar in the filed of VLSI. keep going on making videos sir its is very helpful sir
Thank You sir
Hello Mudasir,
My name is Rahul and I am pursuing my masters in Nanoelectronic systems from Technische Universität Dresden, Germany. Currently I have been allocated 1 academic project : Design of DC-DC Buck Converter in 28nm CMOS Technology. In this work, an integrated switching circuit with an external inductor needs to be designed with converts a 3.7V battery voltage to
output levels from 0.5V to 1.0V at loads between 10μW and 100μW. The conversion efficiency should be analyzed with focus on the properties (stray inductance, ohmic resistance, magnetic core loss, etc.) of the external inductor. Actually the milestone for this project is : (a) Schematic design and optimization of the integrated switching circuits in a 28nm CMOS technology and co-simulation with the Verilog description of the digital control loop. (b) Sizing and analysis of of the external inductor to maximize conversion efficiency within overall application constraints.
I am completely new to Cadence Virtuoso framework. Can you please help me how to approach this project ? Any possible DC-DC Buck Converter schematic diagram.
I would be grateful if could help me in this regard. Appreciate your help.
Thanks and regards,
Rahul Das
Hello Rahul,
As per the schematic of dc-dc converter goes in cadence, we use the general procedure by taking different instances from the foundry Library. However, it is advised first to go with the analogLib instances (for inductor and capacitor). The dc-dc converter has four major components; 1) Inductor. which besides being part of LPF also stores energy and reduces the power loss in circuit. 2) Capacitor, used at the load for overshoot control. 3) Power Stage and Switch Controller. The stability of the feedback loop involved should be ensured. Switch Controller is controlled by signal (Pulse, triangular, PWM). This signal is generated using Verilog. So you have to use Verilog for designing switching circuits.
I would suggest you first go through some literature related to LDOs and then start your DC-DC and a brief overview of poles and zeros in systems, how to locate pole and zeros in circuit. Learn how to find the transfer functions of a circuit.
Finally, Specify which parameter you want to target, like power consumption, stability at low loads, load/line regulations PSR etc.
I will upload a tutorial soon about the Verilog in Cadence.
Happy to help.
Hello Mudasir,
Thank you very much for your kind response and detailed information. Do I need to code in Verilog-AMS for designing switching circuits ? Power consumption and Maximization of conversion efficiency are the target parameters. It would be really helpful if could share your email ID so that I can communicate with you regarding any help in this direction. Also do i need to design power stage of DC-DC Buck converter at schematic level ?
waiting for your kind acknowledgement so that at least in the upcoming weeks I can come up with the schematic design of dc-dc converter.
Thanks and regards,
Rahul
Could you clarify the difference between transient operating point and dc operating point values?
I have not got the component display in the edit option. Are there other methods to show region of operation, gm etc.
I guess you are using the latest version (>IC615). After dc simulation and annotating dc operating points.
There is a wrench like symbol (picture) in the toolbar section of the schematic window (probably in the last row at the end). Click on that you can display these parameters.
But the wrench like symbol in the toolbar is only for annotation setup.
Explore all options there, you will find it
Yes! I got this. It's very kind of you. THANK YOU VERY MUCH.
Can you please tell me how to generate 4 phased clock in cadence virtuso
Write a veriloga code for generating 4 phased clock and make it as a functional block.
Then you can use it any place like a symbol.