complementary metal-oxide semiconductor

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The NMOS and CMOS circuit implementations of (A) a NOT, or inverter, gate, (B) a NAND gate, and (C) a NOR gate. The NOT gate is attached to the outputs of the NAND and NOR gates, respectively, to invert the signal and achieve AND and OR gate logic functions. The small circle at the gate symbol for the MOSFET designates a p-channel device.

complementary metal-oxide semiconductor

electronics

Also known as: CMOS

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June 24, 2026

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CMOS — CMOS A complementary metal-oxide semiconductor (CMOS) consists of a pair of semiconductors connected to a common secondary voltage such that they operate in opposite (complementary) fashion. Thus, when one transistor is turned on, the other is turned off, and vice versa.

Complementary metal-oxide semiconductor (CMOS) refers to a technology used in designing integrated circuits. CMOS technology utilizes pairs of n-type and p-type metal-oxide-semiconductor field-effect transistors (MOSFETs) that work in a complementary fashion. This design allows only one transistor in the pair to be on at any given time, resulting in very low power consumption, especially in standby mode.123

Because of their low power requirements, CMOS circuits are ideal for battery-powered devices like digital cameras and are commonly used in the memory that stores system parameters in personal computers. The development of CMOS technology has been crucial for the miniaturization of complex circuitry and is now the preferred technology for digital applications.234

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12 Key Dates in the History of Photography
1995: The CMOS active pixel sensor patented
…the complementary metal-oxide semiconductor (CMOS), which had been invented about the same time as the CCD. Like a CCD, a CMOS can measure light intensity and color transmitted through a camera’s lenses. Fossum’s improvement on older CMOSs and on CCDs was to adapt computer chip technology so that each…
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…the complementary metal-oxide semiconductor (CMOS), which had been invented about the same time as the CCD. Like a CCD, a CMOS can measure light intensity and color transmitted through a camera’s lenses. Fossum’s improvement on older CMOSs and on CCDs was to adapt computer chip technology so that each…
Read More

digital camera
…charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS), which measures light intensity and colour (using different filters) transmitted through the camera’s lenses. When light strikes the individual light receptors, or pixels, on the semiconductor, an electric current is induced and is translated into binary digits for storage within another…
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…charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS), which measures light intensity and colour (using different filters) transmitted through the camera’s lenses. When light strikes the individual light receptors, or pixels, on the semiconductor, an electric current is induced and is translated into binary digits for storage within another…
Read More

integrated circuit
Complementary metal-oxide semiconductors
Recall that placing a positive voltage at the gate of an n-type enhanced-mode FET will turn the switch on. Placing the same voltage at the gate of a p-type enhanced-mode FET will turn the switch off. Likewise, placing a negative voltage at…
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Recall that placing a positive voltage at the gate of an n-type enhanced-mode FET will turn the switch on. Placing the same voltage at the gate of a p-type enhanced-mode FET will turn the switch off. Likewise, placing a negative voltage at…
Read More

transistor
Silicon transistors
…Wanlass at Fairchild developed the complementary MOS (CMOS) transistor circuit, based on a pair of MOS transistors. This approach eventually proved ideal for use in integrated circuits because of its simplicity of production and very low power dissipation during standby operation. Stability problems continued to plague MOS transistors, however, until…
Read More
…Wanlass at Fairchild developed the complementary MOS (CMOS) transistor circuit, based on a pair of MOS transistors. This approach eventually proved ideal for use in integrated circuits because of its simplicity of production and very low power dissipation during standby operation. Stability problems continued to plague MOS transistors, however, until…
Read More