Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [cmos]

"Complementary Metal-Oxide Semiconductor" is a process which implements a combination of PMOS and NMOS transistors. Most current digital logic is implemented in CMOS. Its cost-effectiveness due to being so widespread means many other applications have become common as well, such as in analog design, image sensors, telecommunication, etc.

CMOS inverter

Further reading
HCMOS Design Considerations, TI Application Note SCLA007A
Moore's Law
CCD vs. CMOS Image Sensors, Wikipedia

CMOS: Circuit Design, Layout, and Simulation, R.Jacob Baker, Wiley

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What' so great about CMOS?

I've read lot of topics here. I read some people saying I prefer to "have CMOS characteristics" & so on , also in some data sheets (like AVR), they say it have CMOS characteristics, etc... I remember once "CMOS compatible" word? So why having…
xsari3x
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Does gate oxide thickness define switching speed of transistor?

This book states that 'a thin-gate oxide is designed to achieve the high speed on and off switching of the MOSFET'. My understanding is that the on-off time of a FET is determined primarily by the gate capacitance of the FET (and of course the…
AlfroJang80
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Please help me explain the overshoot and undershoot in CMOS inverter

Rabaey book says that: Notice especially the overshoots on the simulated output signals. These are caused by the gate-drain capacitances of the inverter transistors, which couple the steep voltage step at the input node directly to the…
Earthgod
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CMOS Circuit Question

I have this circuit for which I have to find the truth table for all imputs whether they are logic 1 (VDD), logic 0 (GROUND) or X unknown. But I am having trouble understanding what I am supposed to do to find the OUTPUT when the imput is unknown..
System
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Using CMOS IC in a TTL circuit

Is it safe to use a CMOS IC? For instance I'll be using a CD4017 in this circuit: http://www.555-timer-circuits.com/police-lights.html Will it still function correctly? Any further modifications needed?
vvavepacket
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What is referred to as CMOS sensor rolling shutter width?

I know what a rolling shutter is. But what is referred to as the "rolling shutter width"? Wikipedia: CMOS sensor: Active pixel sensor Rolling Shutter I don't think Focal Plane Shutter is related because I don't think a mechanical shutter is used. I…
LV3
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Is this CMOS circuit supposed to be an OR or an XOR?

Since it has three NANDs and two NORs I guess it is an XOR, but doing the truth table I'm getting an OR expression. What's going on?
Akari Oozora
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What is the lowest voltage a cmos transistor can operate?

I am trying to do some hspice simulation with some free 45nm CMOS transistor models. I found that an inverter can simulate properly with voltage as low as 0.25V, though it's slower. My question is, in a controlled environment when speed is not a…
kelvin
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Short Channel effect

I have searched for short channel effect in google. There are plenty of articles on that topics, but I can't somehow understand them all. Can you please briefly explain in plain words what are they? What is drin induced barrier lowering in plain…
Man_From_India
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How is CMOS impedance calculated?

The following is a snippet from the book Design of Analog CMOS Integrated Circuits Here is what I thought. $$V_1 = 0-V_x $$ $$V_{bs1} = 0 - V_{s1}$$ $$V_{s1} = I_x r_{o1}$$ According to KCL. $$ g_{m1} V_1 + g_{mb1} V_{bs1} = I_x $$ We can use…
kile
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Can someone explain how I can avoid voltage spikes in this graph?

I’m trying to implement this boolean function using CMOS transmission gate in LTspice. F = AB + A'C' + AB'C I've used two symbols in my project: Transmission gate symbol schematic: 180nm CMOS inverter symbol (PMOS L=180nm and W=720nm)(NMOS…
Ben Paul
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Working of a CMOS inverter

I'm new to this concept and parts of it are a little confusing. I understood the part when a 5V signal is applied as input, a channel is formed in the NMOS device, as the positive voltage attracts electrons, thus output is connected to the ground…
Arun Suryanarayanan
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Finding Vds in a CMOS without info. on channel modulation?

"What would (ideally) be the DC voltage at the output in the following circuit?" That's how the question was formulated. Can it be found without having any information on \$V_A\$ or on \$\lambda\$? The only way \$v_o\$ could be evaluated would be by…
peripatein
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How to construct CMOS equivalent of an XNOR gate using AND, OR, NOT gates?

I am new to digital logic and I am confused hot to construct CMOS equivalent for XNOR gate using AND, OR, and NOT gates. I found XNOR circuit implemented with gates. And what I did is I plugged CMOS circuits for inverter, AND and OR. I doubt it is…
YohanRoth
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Shouldn't the differential pair gain be \$\frac{V_X - V_Y}{V_{in1}-V_{in2}} = -g_m R_D/2\$?

This is a snipet from the book Design of Analog CMOS Integrated Circuits (page 112). This is analysis of differential pair. For \$g_{m1} = g_{m2} = g_m\$, reduces to $$\begin{equation} (V_X − V_Y ) = −g_m R_D V_{in1} \tag{4.21} \end{equation}$$ By…
kile
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