Through-hole technology refers to the mounting scheme used for electronic components that involves the use of leads on the components that are inserted into holes drilled in printed circuit boards (PCB) and soldered to pads on the opposite side.

learn more… | top users | synonyms

3
votes
1answer
34 views

How do I design a through-hole pad in Altium Designer?

I want to define a custom component (TO92 temperature sensor) in Altium Designer with through-hole pads (0.7mm hole diameter, 1.27mm pitch). What is the right way to do this? I I created the ...
0
votes
2answers
109 views

Purpose of oval/oblong PCB through hole pads

What is the actual purpose of using the oval/oblong pads that are commonly used for ICs? Everywhere I read the answer is the possibility to allow a track between the pins, but as long as the pad ...
1
vote
2answers
46 views

Drill hole size suggestion for this pass-through socket

I'm considering using this pass-through socket for a project. Since I'm newer at this, I was wondering what size through-hole would be best? This socket will solder in, so I understand that I can go ...
0
votes
3answers
130 views

Using a mixed technology, SMD and THT components in one PCB

I want change design from Through-hole technology to SMD design. Some components have no SMD version, for example some transistors in TO-92 package, and Power Mosfets, which available in DPAK SMD ...
0
votes
0answers
35 views

Power MOSFET 27N3LH5 for SMT design

I want change existing through-hole type PCB design to SMT design. The existing design use Power MOSFET 27N3LH5 in TO-220(DIP) package and with Heat Sinks in output channels. The SMD version of ...
2
votes
1answer
90 views

Solder through-hole or surface-mount components first?

I am new to surface mount soldering. On a board with both SMT and through-hole parts (header pins), which parts should I solder on first? I imagine the technique I use for SMT soldering is ...
8
votes
5answers
2k views

Hack for fitting 0.04“ leads in to a 0.025” hole on PCB

This might be a ridiculous question to ask - but I have made a mistake in a new library I created in Eagle for a component. The drill diameter of the plated holes for the component leads should have ...
17
votes
3answers
2k views

What are the 'knuckles' on through-hole LEDs and photodiodes for?

I am using an IR LED and a photo diode, and I have designed the PCB according to the specifications that I found on the datasheet - i.e. hole sizes for the pins being 0.6 mm. However, on these ...
0
votes
1answer
143 views

Eagle Cad: change default drill size list

Eagle Cad specifies certain drill and hole sizes, for example, used for VIAs, when routing. I know that I can enter the drill size in the combo box and it will be remembered. But all the other ...
0
votes
1answer
86 views

Maximum protusion length for through-hole component pins

I'm working on a PCB that has through-hole components on both sides of the board. The "top" side of the board is mounted flush to a Delrin plastic block (the only top-side component is a gas sensor ...
1
vote
3answers
214 views

Tips for desoldering difficult to desolder mini transformers

I have to replace a couple of small transformers without destroying the PCB or the transformers. Unfortunately my phone camera is unusable so I need to describe them and what makes the situation so ...
3
votes
3answers
153 views

Removing PCB from complex pattern of soldered-in thru-hole posts?

I have a PCB mounted to a chassis with 16 feedthrus, the feedthrus posts are soldered to plated thru-holes in the PCB. I would like to remove the PCB from the chassis, the problem is that I am unable ...
0
votes
2answers
108 views

Can the metal tab at top of a TO-220 package be cut off?

I am using a TIP120 Darlington transistor in a through-hole (specifically TO-220) package, in a very simple application which does not generate much heat. I remember reading that the metal tab at the ...
-1
votes
1answer
419 views

Esp8266 (esp-03) breakout

Recently, Hackaday is talking a lot about the esp8266, a wifi to serial chip. I want to use the esp-03, a breakout with half-hole connectors that has 2mm pitch. Is there a breakout board that can turn ...
2
votes
1answer
144 views

Surface Mount vs Through Hole Aluminium Electrolytic Capacitors?

What are the differences between SMD and TH Aluminium Electrolytic Capacitors? Why are TH variants available with such greater lifetimes? (For example, Digi-key has SMD aluminium caps up to 10k hours, ...
4
votes
2answers
913 views

Is there any pattern or standard to through-hole resistor sizes?

I've long been under the impression that a quarter-watt resistor has a standard package, and a half-watt resistor has a standard package, etc. But I've recently gotten through-hole resistors which are ...
1
vote
4answers
228 views

High precision soldering of through hole components

I have a through hole component with many leads spaced closely together, see picture: I'm looking to unsolder it from the PCB and then solder it back again. Unfortunately, the leads are spaced so ...
2
votes
4answers
758 views

Holding components without bending leads when soldering upside down?

I am gaining experience in soldering components onto PCBs. I'm working through some one sided through hole PCBs and one thing that I'm having trouble with is holding components once I flip the board. ...
1
vote
1answer
87 views

Plated hole without circles on layers

I am a beginner on Eagle. I want a make a plated hole on PCB but no any pad on top or bottom layers. Or, a plated hole on PCB but bottom and top layers are electrically isolated. Another variation is ...
3
votes
2answers
281 views

Passing copper traces between two THT pins

I've been working on a small project as an extra activity for a basic digital electronics course I was taking, in which I had to design a TTL-logic based PCB, and etch it. I've been using Ultiboard 11 ...
0
votes
1answer
369 views

Do high power through hole resistors need a heat sink

I'm using the following resistor: click. To be precise, the MCKNP05SJ050KAA9 found here. From what I've been able to determine, my device is the ...
9
votes
1answer
834 views

Round female pin header vs square female pin header

What are the main differences (except for the obvious, one is round one is square) between the round pin headers and the square ones? Or differently asked: Why would someone choose round pin headers ...
2
votes
2answers
242 views

Can someone verify the hole diameter is correct?

I'm looking at this current sensor (datasheet) I'm a little confused at this notation for hole size. Pin 5 and 6 have a diameter of 0.6mm while pin 1, 2, 3, 4 have a diameter of 0.25mm ? Is that ...
11
votes
4answers
15k views

What pad hole (drill) size is appropriate for a given through-hole lead diameter?

I am making some new through-hole parts in Eagle for components that are not already in the various libraries. I've realized that the drill size needs to be a little larger than the lead diameter, but ...
5
votes
1answer
6k views

Advantage or disadvantages of SMD over Through hole design in high frequencies?

I know this is an elementary question. I know that SMD design has the advantage of smaller board size but I dont know which design works better in higher frequencies.
23
votes
2answers
2k views

How can I reverse engineer a simple through-hole board?

How can I reverse engineer a simple through-hole board? Trying to do it by eye gets confusing because it's easy to lose track of component orientation and location while flipping the board over. Maybe ...
2
votes
2answers
1k views

Drill files from Kicad for PTH and NPTH

I have a board in Kicad that uses a mixture of plated and non-plated through holes. It generates two drill files for these. However, manufacturers seem to expect only a single file. If they don't ...
3
votes
5answers
707 views

2 Layer Through Hole PCB

I am designing my very first PCB for a robotics project I am working on. The project will be using through hole components. I was not able to get all the traces to work on 1 layer, so I added a ...
20
votes
4answers
1k views

Do engineers still design for volume using discrete through-hole bipolar transistors?

As a hobbyist who likes plugging BJTs and discrete components into solderless breadboard for entertainment and education, I recognise that people like me are an insufficient market to make it ...
3
votes
1answer
242 views

PCB has strange looking pads, how do I solder them without impacting nearby surface mount components?

I've recently brought the px4fmu and px4ui boards. The px4io requires me to solder a power socket and headers onto it. However there are surface mount components very close to the holes/pads. Also ...
4
votes
4answers
8k views

How can I make a plated-through hole in Eagle?

I have mounting holes (0.125 in) at the corner of my PCB project in Eagle, made with the standard "hole" tool. However these are not electrically connected to anything. There doesn't appear to be a ...
2
votes
3answers
984 views

Breadboard/veroboard and SMT

By now, through-hole components have almost completely disappeared from consumer devices and also professional PCBs. But what is the alternative to build breadboard-veroboard for SMT technology? ...
2
votes
2answers
192 views

What does “Pins are on 0.17” centers" mean?

I'm looking at some switches (here) and the description reads: Small PC mounting slide switch features SPDT contacts and white positive action slide lever. Size about 0.56"L x 0.25"W x 0.34"H ...
15
votes
5answers
7k views

Plated Through Hole at home?

Is it possible to make PTH (Plated Thorugh Hole) at home? Can somebody explain the procedure?
7
votes
3answers
2k views

What's up with these plated through-holes / vias?

We purchased a number of stainless steel kiosk keyboards from a Chinese manufacturer a while back and have been seeing extraordinary failure rates (around 30%). Groups of keys just stop working. ...