Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
Spice and IBIS
I am trying to simulate a circuit in ltspice. Most of the circuit is done, but i cant find the spice models for a couple of components. I found IBIS 3.2 and hspice models for these, but I could not convert these to spice models. I tried a few softwares like the orcad 16.6 demo...
Lets say system is designed for max 5A. The user should be able to configure it like this -
Run the system at 2A, with 10% duty cycle at 10khz.
Microcontroller's dac will give me a voltage representing the 2A on a 5A scale. UC will also give me the pwm signal. Now the mosfet should drive the...
How do I feed this signal to a mosfet? My switching speed can be as much as 1mhz and I dont have enough current in this signal for fast switching. I looked at quite a few mosfet driver chips, but most of them are suitable for dc-dc converters or for h-bridges. I found a few simple ones but those...
Basically I want to control a mosfet with this signal. I want the analog signal to control the current level and pwm for controlling the switching at the same time. Current capability might not be there so i will need to use a mosfet driver or something like that.
i have another question related to PWM so I guess i will add it here. How do I calculate the power requirements for components while using PWM.
e.g. if I use a 1 ohm current sense resistor for 5A current, I need a resistor of 25w + some margin. How much wattage resistor do I need if I am going...
I have a analog dc signal for which the voltage varies from 0-1.23v. I also have a 3.3v pwm signal, for which the worst case frequency will be 1mhz. I need to merge these two so that the output signal is switched as per the pwm but the voltage level is as per the analog signal, kinda like a...
I want to try the first circuit in the link you posted above. I have 0.5 ohm 5w and 1 ohm 2w for the current sense resistor. lm317 is on a decent sized heatsink. Is 1k a good value for the base resistor r2. I currently dont have a pnp bjt, I should be able to use a p channel mosfet instead...
I also have a simple lm317 based supply that had a minimum starting point of 1.2V, which is as per the datasheet. I tried the circuit mentioned at the link below to get down to 0v. It doesnt seem to work for me. I used a tip31c as the transistor. I am using a 12v dc supply for input instead of...
thanx for the help guys, i tried with a -ve rail and it works fine, I get an offset of 44mv, which is ok.
I will try to answer all the questions here.
What is the highest frequency of your signal?
Right now I am just trying to test the concept, but eventually it will go to about 1mhz, square...
i was trying to do a simple voltage follower but I am seeing a very high offset voltage, about 1.8-2v. I am using a 12v-gnd supply. I used a 10k feedback resistor and grounded the non-inverting end.
Even when i apply a signal to +ve terminal that varies from say 0-5v, I get steady 2v output...
The molex connectors are rated for 12v only. I need to handle upto 30v. Not sure which faston connectors you are referring to, there are quite a few different types of them google throws up.
I need to carry about 25A current from the psu pcb to another pcb. Distance will be about 6 inches. Max voltage will be about 30v. Any suggestions. Its better if the size is not too big. I would prefer to have a m/f connectors with wires rather than the wires being screwed straight into a terminal.
chip i am using wants max input of 22v, so the 21v need. i dont need exact value, but it shouldnt drop too much. about 20v min. I guess that isnt exactly regulated.
I would probably need about 25 amps capability to use 20a from the smps. cost is of course an issue, dont want it to be...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.