Altium looking for a voltage regulator - Page 1
Forum section: electronics / beginners

author: nForce
author_rank: Frequent Contributor
timestamp: January 03, 2016, 05:08:23 pm
content: Hello,I am new to Altium, and I understand that I need libraries which contains components to draw a schematic.I have downloaded the library package of Texas instruments to find a lm2574 voltage regulator, but I can't find it. I have installed all the libraries in Altium and used the advanced search button, but the query I get is empty.Can someone add the link for the library which contains lm2574 or something similiar to this voltage regulator?Thank you.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 03, 2016, 05:11:30 pm
content: Do you need a simulation model, or only schematic symbol and footprint?Typically, one ignores the standard libraries (because they suck), and makes symbols and footprints by hand. It's not very time-consuming, and you'll need to learn how to do it, sooner or later.Tim

author: nForce
author_rank: Frequent Contributor
timestamp: January 03, 2016, 05:34:23 pm
content: Isn't the point of programs like Altium to simulate, because I can draw the schematics on a paper?So if I make the symbol and the footprint, how can I connect the behaviour of the chip in real life to this symbol in a program?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 03, 2016, 06:34:22 pm
content: Well, you can't connect a paper drawing with live supplier links, PCB netlists, design rules and more...Check out Altium's tutorial/instruction on adding simulation models to schematic parts. The hard part is finding a model that works well enough; it's becoming a thing, these days, where manufacturers either lock their models (e.g., HSpice, LTSpice, PSpice and probably others all support encryption), or write them specifically for their looks (ADI's thing, TI's TINA thing).Don't forget to create a 'test bench' simulation to demonstrate that your model works and is linked properly. To test a switching regulator, you'll want to at least measure the supply voltage and current (including current waveform to make sure it's reasonable), rise and fall of the switching node, and output voltage accuracy for a few different loads and input voltages. DC and AC analyses will be useless, unless it's an average mode switching model, which is dubious in and of itself.For use in a larger simulation, you're much better off replacing it with a voltage source and a dependent supply side load. Or just a source, if you don't need to add up all the load currents (which should be easily enough done on paper, speaking of!). You get very, very little advantage having a switching supply in a larger transient simulation, and all the extra nodes and switching will severely slow down the simulation (or make it unstable, who knows).Tim

author: nForce
author_rank: Frequent Contributor
timestamp: January 03, 2016, 06:54:51 pm
content: I can't even find the lm2574 part. How can I then find an appropriate simulation model?I think it is an overkill for a beginner to make this. Can I get a link for a symbol and footprint?And i would also need the connector for a wall socket 120V/230V or whatever the voltage. Where can I find a connector for three wires, which are earth, neutral and live?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: January 03, 2016, 07:24:38 pm
content: No, you make the symbol and footprint yourself, and you link the model file from a third party. In general, you will not find all three in the built-in libraries, at least not good looking ones. Libraries with models are particularly thin.The manufacturer's product page is here:http://www.ti.com/product/LM2574I don't see SPICE models listed, so you're stuck.And also like I said, do youreallyneed to simulate a DC-DC converter?There are many connectors for three wires. You can use direct soldered wires, crimp terminals, screw-down connectors, pluggable connectors, the list goes on. Anything rated for the voltage and current will do. (Line voltage up to 250VAC single phase generally requires a 1.5kV peak transient rating.)Tim

author: marshallh
author_rank: Unknown
timestamp: January 03, 2016, 07:29:59 pm
content: The consensus seems to be that using Altium for simulation is like using a minivan to haul building supplies. Technically, it IS capable.Folks that need high speed simulation, example for finding noise margins on DDR3 busses, you export the PCB to an intermediate format and load it in Hyperlynx.On the other end of the spectrum you can use the excellent LTSpice and not bother with making a PCB.

author: tautech
author_rank: Super Contributor
timestamp: January 03, 2016, 07:37:16 pm
content: For the OP, member free_electron's library might be useful:http://www.siliconvalleygarage.com/downloads/altium-library.html

author: Christopher
author_rank: Frequent Contributor
timestamp: January 03, 2016, 07:45:39 pm
content: It's not hard to make your own PCB layouts and IC layouts in altium. It's a breeze !I normally copy the symbol from the supplied library because some of their schematic symbols are quite nice.

author: nForce
author_rank: Frequent Contributor
timestamp: January 03, 2016, 08:50:26 pm
content: Quote from: tautech on January 03, 2016, 07:37:16 pmI would like, to get the screw-down connectors. Are they in this library?

author: tautech
author_rank: Super Contributor
timestamp: January 03, 2016, 09:03:26 pm
content: Quote from: nForce on January 03, 2016, 08:50:26 pmWhose connectors? Brand?For other than jelly bean parts Altium libraries are listed by part manufacturer and this often make finding specific parts tedious if they are not found with the search facility as often is the case. Getting the syntax correct in searches is key for quickly finding parts.Altium is a very powerful package but it does take time to become proficient with and I'll be the first to admit I'm no expert.

author: poorchava
author_rank: Super Contributor
timestamp: January 04, 2016, 01:19:13 pm
content: Better use a dedicated simulation software for simulations and Altium for pcb design. Most component models which you can get from manufacturers' websites are written and tested for pspice or ltspice (pspice has majority). There are some things which can be done in pspice but won't work in ltspice and vice versa. It will be the same with Altium.PCB footprints and schematic symbols are for you to make on your own to your liking. The reason is that virtually every company has some internal rules for creating documentation. For example in my company we have additional layers that are used to create assembly drawings for manual assembly workers and repair technicians. Altium contains a really nice wizard for creating IPC compliant footprints and you can adjust the footprint later.Sent from my HTC One M8s using Tapatalk.