11

In a very simple form, relative to VCC, think of the transistor as either coming before or after the device. If the transistor is connected between VCC and the device, it is sourcing current. If the transistor is connected between the device and ground, it is sinking current. (Image from CircuitsToday.com) Some articles that describe things in more ...


10

JYelton is right, and probably this is what whoever said "NPN transistors are sinking and PNP are sourcing devices" had in mind. But, that's not the only way to use a transistor. For example: simulate this circuit – Schematic created using CircuitLab This configuration is called common collector or emitter follower. Now the NPN is sourcing, and the ...


8

This isn't a question with one clear answer, and this problem is one of the big reasons why larger companies trying to outsource to China will always send somebody to oversee the process locally. In general, this is not a question of 'how to handle these matters', but it is a question of specifically which regulations you need to comply with. Before you ...


7

There are few professional services which integrate notifications from manufacturers and can manage your BOM: IHS: PCMS, BOM Manager, PCNAlert, etc. SiliconExpert Probably others I'm not aware of. Most of big companies in aerospace and defense business subscribe to one of these services but they have dedicated component management departments. Also only ...


6

Try using an inexpensive power relay such as the T90 series, and attach it to a resonator board which will act like the cone of a speaker. They draw about 1W each. Since you're after an aesthetic effect you'll have to fiddle with it, I think. Now if you really want buzzy clanky sounds, you can consider an AC powered "definite purpose contactor" as used in ...


5

I found the component! Name: PCB Test Point, Copper, Gold Plated Contacts Manufacturer: MULTICOMP Part number: TEST-3 Reseller: http://uk.farnell.com/multicomp/test-3/test-pin-pcb-1mm/dp/1702006 Datasheet: http://www.farnell.com/datasheets/1680152.pdf


4

The definitive answer in your case (US) is ITAR and the USML (US Munitions List) readily available on the state department web site. The easiest for you will be to check with the manufacturers. The USML parts will definitely tell you. Some distributors slap warnings on everything which frighten people off. You need to check on a case by case (or rather ...


3

Now, I read some information online and from what I got on forums, NPN sensors are current sinking devices and PNP sensors are current sourcing devices. So that tells me that I have to go with a PNP output, since a sourcing sensor output must go with a sinking input. You are correct. In Figures 1 and 2, below, an external sensor is connected to a PLC input....


3

I used to work for one of the big semiconductor companies, and our policy was to redirect any queries for less than 100k parts to the distributors. We were already too busy providing support to the large customers, the ones that would buy 15-20M parts a year. The 1k pricing you see on the websites has become a standard that aids engineers when it comes to ...


3

Updated link Is this what you're looking for? Part number 5-103639-3 from TE connectivity


3

TL;DR: The part you've picked is adequate for all but the most humongous relays (at least to 1A coil current and coil voltage of 24V or more). As Andy says, the peak current is just the maximum relay coil current (maximum input voltage divided by minimum coil resistance (use the minimum 25°C coil resistance, adjust it for the lowest ambient temperature ...


3

Firstly, why <3 dB? This is a ridiculously strict requirement for general use, so do you have a specific need for zero noise? This aside, the lowest-noise power supplies are linear. This is a basic circuit that pretty much looks like: transformer -> rectifier -> smoothing capacitors -> regulator -> more smoothing capacitors See this article for more ...


3

According to this datasheet that I found in a google search, they're calling that a "spring pinned socket." Unfortunately, I wasn't readily able to find anything similar by searching Google, Digi-Key, and Mouser (where I found the datasheet) for that term. - - - - - - - - - - EDIT - - - - - - - - - - Upon re-examination of your photo, there's technically ...


3

Kapton (polyimide) tape is brown, like the flat flex cables. The tape in the photograph is clearly green and seems to be polyester tape, not polyimide--powder coating masking tape, specifically. It is similar to Kapton in its mechanical properties (including heat resistance) and uses a similar silicone adhesive, but costs less and has poorer chemical and ...


3

No. That chip is just a bunch of transistors with their emitters all connected to comm (pin 9). You can't do high-side switching with them. Figure 1. Image from SE. The ULN2803 consists of eight Darlington transistors connected to a common pin. Each output can switch up to 500 mA to common. The maximum current the common can handle is 2.5 A (but I ...


3

Even at volume Sony is not always interested in playing along :) The higher you go in resolution/performance with image sensors the harder they will be to get. The good stuff will all require an NDA, which will mean they want to look at your business to see if they even want to engage. I would recommend you start with modules like you say. I don't know ...


3

Some distributors send me the end of life notifications and change notifications for components that I have purchased from them. DigiKey and Mouser do this. Buying components from them have automatically subscribed me to the change notices. But... I haven't heard any statements about coverage. Does this work for every component and supplier in the ...


3

(This is not legal advice, just my understanding as someone who deals with this stuff professionally). If something is ITAR controlled you must not export it (or even detailed documentation regarding it) without the proper paperwork (probably a permit). Some kinds of sensors and other things are covered, as well as actual munitions. Likely if you're ...


3

DS18B20 is the part number for a component made only by Maxim, formerly Dallas Semiconductor. The 'DS' prefix stands for 'Dallas Semiconductor'. DS18B20 is not some sort of general noun for what this component is.


2

We outsourced assembly to China only once, and we've got our whole component shipment delayed at chinese customs for a month for just one component: a simple JST plastic through-hole connector. We've got GPS units, MCUs, resistors, capacitors, opamps, etc. in our shipment, but that particular connector was problematic who knows why. It was held in customs ...


2

Consider using a "pinball knocker", essentially a solenoid that strikes the inside wall of a pinball cabinet (or a strike plate of its assembly) to make that rapid clacking/knocking sound an various points in the game. Tuning the control of that solenoid and the object it is striking can get you anything from a rapid series of clacks to a single dull thud ...


2

You might want to consider an auto starter solenoid. That is something you could get as salvage. If you want a big sound from something very small, you will need to reproduce the sound.


2

Transformers are difficult to source in general. My recommendation based on past experience designing low volume one-off flyback transformers is to build your design around the transformer, not vice-versa. Coilcraft is an example of a company that sources stock transformers suitable for flyback applications. I'm providing this as general advice for people ...


1

Sinking 2 mA 0.4 V maximum means the source resistance is 0.4V/2mA = 200 Ohms which can deliver 15mA with a small series current limiting Resistor. If using IR LED's with 1.2V drop from 5V then a total series resistance of 3.8V/15mA= 250 Ohms. If the driver is 200 Ohms and LED is about 10 Ohms then a series R of about 40 Ohms is needed. If a RED LED is used ...


1

clunky solenoids with a battery just slightly above the Vmin for the coil will be the slowest chatter clunk, and then the max rated voltage for the coil will have the loudest but solid clunk. for small relays here's 4.5V one that can be mounted glued to a panel to amplify the sound,that will,operate from a LiPo cell down to 3.1V http://www.digikey.com/...


1

Solenoids usually produce a loud click so use internally a solenoid that activates when any of the relays activate. The solenoid doesn't have to do anything useful of course.


1

It will probably be smaller, cheaper, and easier to implement to mimic the sound of a relay than to use a genuine relay. Relay actions only take a few 100 ms at most, even for really big klunky ones. Even the sound simply recorded and played back thru a small PC mount speaker wouldn't take much memory. Let's be pessimistic and say you need 12 bit samples ...


1

A lot of relays may advertise how quiet they are. So you can check the datasheets for louder relays, or those that do not specifically advertise so. As an example see this datasheet: random relay datasheet You can see that there are a few models Low Noise Models: G5RL-1A(-E)-LN High-Inrush Models: G5RL-1(A)-E-HR, G5RL-1A-E-TV8 etc Avoid the low noise ...


1

As someone who has made FLASH, I would say that you should just use a MicroSD card. Firstly, it's really easy to get. Secondly, you cannot probably afford the cost of dealing with suppliers for what you'll get out of it. Most FLASH storage is relatively low power to read, but writing takes a lot more power. My FLASH took 1nA per bit for 1uS to program at ...


1

I have seen it being sold in china eshops like this or this Or alternative versions like this


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