CMOS technology is the core of all modern digital electronics. Almost every integrated circuit today is fabricated using CMOS technology because it offers extremely low power consumption and high integration capability. In embedded systems, learning CMOS technology is mandatory because microcontrollers, processors, memory ICs and sensors are internally built using CMOS technology. The popularity of CMOS technology comes from its low static power, high noise immunity and scalability, which is why CMOS technology dominates today’s semiconductor industry.
CMOS technology (Complementary Metal-Oxide-Semiconductor) is the foundation of all modern digital ICs. In CMOS technology, NMOS and PMOS transistors work together in a complementary way to form logic circuits. Almost every microcontroller, processor, memory IC and system-on-chip today is fabricated using CMOS technology.
These CMOS technology advantages make it the dominant semiconductor process.
| Terminal | Name |
|---|---|
| G | Gate |
| D | Drain |
| S | Source |
| B | Body / Substrate |
The gate voltage controls MOSFET channel formation. When the gate exceeds the threshold voltage in MOSFET, a conductive channel forms between source and drain.
This complementary behavior is called NMOS and PMOS operation, the heart of CMOS technology.
The CMOS inverter (also called CMOS logic inverter) is the simplest CMOS gate.
| Input | PMOS | NMOS | Output |
|---|---|---|---|
| 0 | ON | OFF | 1 (VDD) |
| 1 | OFF | ON | 0 (GND) |
The CMOS inverter VTC curve plots output voltage versus input voltage and shows a steep transition, proving the reliability of CMOS technology.
Ideally zero because there is no DC path between VDD and GND in steady state.
P = α × CL × VDD2 × f
Where: α = switching activity factor, CL = load capacitance in CMOS, f = operating frequency.
| Feature | CCD | CMOS |
|---|---|---|
| Fabrication | Special process | Standard CMOS technology |
| Power | High | Very low |
| Speed | Slower | Faster |
| Integration | External ADC | On-chip ADC using CMOS in VLSI |
| Mobile usage | Rare | CMOS sensor in mobile phones |
| Feature | NMOS | PMOS |
|---|---|---|
| Charge carriers | Electrons | Holes |
| Gate condition | HIGH | LOW |
| Network role | Pull-down | Pull-up |
| Connected to | GND | VDD |
| Speed | Faster | Slightly slower |
To master CMOS technology, join the best embedded course in Bangalore – IIES. IIES also provides the best VLSI internship in Bangalore, covering CMOS inverter design, CMOS gate implementation, CMOS in VLSI chip flow, and practical CMOS simulation projects.
From CMOS inverter, CMOS gate, CMOS logic inverter, XOR gate with CMOS, to camera applications like CMOS sensor in mobile, everything today depends on CMOS technology. Whether it is CCD v CMOS comparison or designing chips using CMOS in VLSI, the foundation always remains CMOS technology.
CMOS technology uses complementary NMOS and PMOS transistors to build low-power, high-speed digital circuits.
It offers very low power consumption, high noise immunity, and excellent scalability for VLSI chips.
A CMOS inverter is the basic logic circuit made using one NMOS and one PMOS transistor to invert the input signal.
CCD sensors consume more power, while CMOS sensors are low-power, highly integrated, and used in smartphones.
CMOS technology enables compact, low-power processors and SoCs, which are the core of modern embedded systems taught at IIES – the best embedded course in Bangalore.