Recent content by likephysics

I did use LTspice and learnt how to plot power, which I did not know before. According to simulation, the Ac termination power is 10x lower than just resistor termination for the same freq, amplitude. I find it that knowing how to do it outside simulation is the key to understanding.

DaveE, thanks for link and the answer. I was trying to use C*V^2*f and then use 20-30% of the result to account for rise and fall time. There's also power dissipated by the resistor during this duration, right?

The AC termination is used to terminate DDR4 clock. Other than this, I haven't see AC termination much. See page 8 of this app note: https://community.nxp.com/pwmxy87654/attachments/pwmxy87654/imx-processors/188384/1/AN5097.pdf DMM ref designs also have AC termination on the clock.

How do we calculate power dissipation for AC termination on a clock signal? The resistor is dissipating only at the edges(assuming a square wave).

I was trying to figure out the equivalent circuit starting from R3 to the load R2. Let's say R2=100 and T2=50, then the part from R3 would reduce to Voltage source of 0.33V with series res of 25 ohm and a T line of 50 ohm? The 25 doesn't make sense. Since R3=T2, this series res would be 0...

Trying to work out the match for a transmission line with 2x termination. Like the one here: https://ibb.co/p4dY7pF V1=1 R1=R2=T1=T2=50, V1 sees R1 and T1. So it is divided to half. Now you have 0.5V source with a 50 Ohms series impedance(T1) looking into a load that is a parallel combo of...

I have attached a ckt to make it clear. Assume gate threshold is 1v. In the fig, if Source (Low side) is 0V, then Vgs > Vth, FET is ON. Let's say Source is 3.3V, Gate is 3.3V and Drain goes from 3.3V to 0V. At what drain Voltage does the FET turn ON? What is the turn on sequence. Does the body...

When does an N-ch Mosfet conduct when drain voltage varies from 0V to Vdd(like 5V). In case of Source voltage changing between 0V to 5V, all you do is check if VGS > Vth, with Vdrain fixed at 5V. But in case of Drain Voltage changing between 0V to 5V, how does it work?

How does the load capacitance affect the Crystal. For example, IC manufacturers recommend a Crystal and also load capacitance, like 25MHZ, 16pF. What happens if I choose a xtal with load cap of 10pF 25MHz? I am talking about changing the load caps recommended by IC manufacturer, not the ones in...

So if I terminate a 50 ohm source with a parallel 50 ohm followed by a matched tline and load. The load will see half the voltage, right?

You read it right. why doesn't the half power dissipation happen when the 50 ohm tline is terminated by 50 ohm load. Let's say we have a 1V source with 50 ohm source impedance driving a 50 ohm tline. The voltage on the tline would be 0.5V. Now if the tline is terminated by 50 ohm load, the...

I am a bit confused on source impedance and Tline impedance, when both are equal. Let's say source impedance is 50 ohms and Tline imepdance is also 50 ohms. Why does the incident wave divide between the source impedance and tline impedance. The impedance is same, so reflection co-efficient...

Is the pottery kiln have an inductive element? As you mentioned you could try using a RCD or just a RC snubber. Why can't the Fujitsu Micro drive SSDs. There are SSDs available down from 3.3VDC to 220VAC

Gordo, What exactly do you mean by pitting the contacts?

What are the conditions when a ESD discharge occurs, in particular while handling components and assembled units. Can someone explain ESD discharge in the following cases - Let's say you are handling an IC, moving it around for soldering etc. What is the chance of the handler zapping the IC and...