HackMD
Lab 1 2nd Feb
Basics of CMOS Technology
NAND : pMOS in parallel { remember by APP, A : (N)AND, P : pMOS, P : parallel}
Types of analysis
Transient : calculates a circuit's response over a period of time defined by the user
To calculate
- Rise Time
- Fall Time
- Delay Time
Open LTSpice XVII
Add component => serach for voltage
Right click on the voltage component, click on advanced settings, and give the parameters to make the source V-pulse.
Add components, R : 1kΩ ohm C : 1µF
Connect components with wire, add a ground reference point.
Right click on the schematic, create a Label Net, to observe voltage at a particular point.
Click on the label-net, to observe the voltage trend. To compare the output with input, also create a label-net for the input side.
Observations
Peak Voltage 5V
| timestamp | voltage | remarks |
|---|---|---|
| 1.71ms | 0.5V | Reaching V10 at charging |
| 23.41ms | 4.5V | Reaching V90 at charging |
| 102.56ms | 4.5V | Reaching V90 at discharging |
| 124.39ms | 0.5V | Reaching V10 at discharging |
Lab 2 missed
Lab 3 16th Feb
CMOS
Create symbolic, schematic, merge and run
Lab 4 23rd Feb
Transient and DC analysis for the following
To create symbol
- Hierarchy tab
- Create new symbol
| param | pulse 1 | pulse 2 |
|---|---|---|
| v_initial | 0 | 0 |
| Von | 5 | 5 |
| Tdelay | 0 | 0 |
| Trise | 0.001 | 0.001 |
| Tfall | 0.001 | 0.001 |
| Ton | 0.1 | 0.2 |
| Tperiod | 0.2 | 0.4 |
NAND gate
Schematic
Truth Table
| A | B | Output |
|---|---|---|
| 0 | 0 | 1 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
NOR gate
pMOS in series, nMOS in parallel
Schematic
Truth Table
| A | B | Output |
|---|---|---|
| 0 | 0 | 1 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 0 |
Lab 5 8th March
XOR
Schematic
Truth Table
| A | B | Output |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
XNOR
Schematic
Truth Table
| A | B | Output |
|---|---|---|
| 0 | 0 | 1 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Lab 6 15th March MuX
4x1 MuX using CMOS
2x1 MuX using CMOS
To create 4x1 MuX using 2x1
Lab 9 12th April
Viva Questions
Why to use CMOS technology ?
- Less power dissipation
- Compact, saves space
- Large noise tolerance
When to prefer BJT over CMOS ?
Faster speeds, as in CMOS
