Printed circuit boards prove crucial to the functioning of electronics. It not only ensures that electronic device circuits transmit electrical and mechanically sound signals but that the device works properly. While at RayMing PCB and Assembly, you will probably get a wide-ranging list of PCB services; crucial elements that allow PCB usage can often go under the radar. Similar to how a PCB proves instrumental to an electronic device, a PCB header plays the same function in a printed circuit board.
Printed Circuit Board Headers
PCB headers, also referred to as PCB pins, entail a crucial electrical connector instrumental in allowing you to join diverse connections to the printed circuit board by utilizing one block. By design, a PCB pin header typically gets mounted and soldered onto the board’s surface, which allows the alternate side to allow connections. The PCB header connector has pins that get shrouded to ensure a studier and secure unit besides averting incidences of pins bending.
Importance of PCB Headers
It becomes crucial to use PCB headers to allow for numerous PCB electrical connections through a single connection block. What’s more, these PCB pin connectors prove simple to use as you only need to solder it into the board to proceed with making connections to many pins. Each pin can have a distinct use, like, for instance, power or data.
PCB headers also play an integral role when it comes to introducing learners to electronics. It not only proves simple to comprehend but has one primary function to allow wire-to-board connections. Therefore, it becomes common to incorporate kits, learning boards, and other accessories, especially single-board computers.
PCB Header Types
Printed circuit board headers come as shrouded or non-shrouded pin headers. In helping you to understand this, shrouding implies the housing of connections using plastic cases. Shrouded connectors, therefore, prove robust and with an unlikelihood of causing short circuits. However, these types of headers occupy more PCB space. On the other hand, pin headers prove easier to operate besides possessing diverse and wide-ranging applications.
Only three types of PCB headers exist, and it includes the following.
- Double-row or single pin headers
- It represents one of the widespread and popularly used headers. The double-row or single pin headers get produced as matching female and male versions. Additionally, they get derived from a doubled-over sheet metal possessing a square cross-section.
- Angled connectors: Angled connector headers come in a range of diverse angles. Angles include 180° and 90°. Such headers prove useful whenever you have to reduce a cable’s strain or require extra board room (horizontally or vertically).
- Machine-pin headers. Such a header possesses a spherical cross-section that fits more into the round printed circuit board holes. It, therefore, provides an enhanced electrical connection, increased lifespan, and greater durability.
Basics of Connectors
Header connectors encompass many diverse connection options. Essentially, one side has a pin that gets soldered to a printed circuit board. The pins can either prove right-angled or at 180° to the PCB surface. Additionally, these connectors come in a range of pitches. Therefore, it can end up having numerous individual pin rows.
However, the most common pin header encompasses the 2.54mm double or single row connectors. It comes as a typical breadboard attuned pitch. As earlier enumerated, these pins come from female and male versions. The connectors prove common in connecting Arduino boards with shields. Additionally, users can connect the jumper wires to the breadboards easily.
However, other pitches prove uncommon, and an excellent example includes the wireless XBee module that utilizes a 2.0mm pitch type of the connector above. One typical variation of the XBee entails the “machine pin” version. The standard version gets formed from folded and stamped sheet metal, and the machine pin connectors arise from tooling the material (metal) into the preferred shape. Here, the outcome becomes an extra robust connector, complete with an enhanced joint beside a longer lifespan, making it more expensive.
Cables used in connecting these pin headers come as two connector types: ribbon cables containing insulation displacement connectors or individual wires containing crimp connectors. The ribbon connectors can get clamped onto ribbon cable-ends, consequently establishing a connection to every conductor in the cable. By and large, cables only come as females with a corresponding male pin to allow successful coupling.
Flexible circuits also get to utilize solder tabs, all spaced at the 0.1″ standard pitch. In establishing contact with the material (semi-conductive), the tabs get stapled through the flexible substrate.
Based on your skill set and project application, you can use a few connecting methods to the solder tabs. You can solder to the pins directly or introduce the solder tabs into the breadboard. However, it becomes crucial to note that the solder tabs (thin) can break over time, especially when bent excessively. Additionally, the pins can also become loose on the breadboard socket, besides the flexible sensors becoming sensitive to high temperatures due to the semi-conductive material. Therefore, as an excellent alternative, the advent of the connectors: Amphenol FCI Clincher, came as a lifesaver because the design encompasses breadboard-compatible sockets and thicker leads to ensure an extra reliable connection.
Important Connector Terminology
Since PCB header act as a crucial enabler for connections on the printed circuit board, it becomes essential to understand some basic terms commonly used with connectors.
- Gender. Connector gender implies whether a connector plugs in or gets plugged into and thus gets categorized as either female or male, respectively. Unfortunately, in some cases, connectors can appear as female yet get classified as male.
- Polarity. In almost every case, plenty of connectors allow connection in a singular orientation. It is a trait inferred as polarity, and those connectors with means of preventing themselves from getting connected the wrong way come inferred as polarized or keyed.
- Contact. It entails the connector’s business-end portion. Such portions come as metallic and tough one another establishing a connection (electrical). However, it also features a couple of challenges as contacts can end up becoming oxidized or soiled. Alternatively, the springy nature needed to secure the contacts fades together with time.
- Pitch. Plenty of connectors comprise a collection of contacts, all in a repetitive pattern. The connector pitch denotes the distance from one contact’s center to the same of the subsequent contact. It becomes vital because plenty of these contact families appear similar but can differ regarding their pitch. It, therefore, makes it difficult to determine whether the purchase completed proves the correct mating connector.
- Mating cycle. All connectors prove finite in their lifespan. The disconnecting and connecting process of these connectors degrades them. The information is presented in datasheets as mating cycles, though it varies from one tech to another. For instance, a USB connector can last a lifespan of thousands of these cycles. In contrast, a board-to-board connector primarily used in consumer electronics can have tens of these cycles. Therefore, it becomes vital that you pick a connector possessing an ideal life for a respective application.
- Mount. It can often confuse a lot of people due to the underlying implication of having diverse meanings. The word “mount” can infer to a myriad of things: for instance, how the connector gets mounted on the panel (panel mount, board mount, and free-hanging), the relative connector angle to that of its attachment (right-angle or straight), or the mechanical manner of attachment (surface mount solder tab, through-hole).
- Strain relief. It implies the relief you provide to a connector mounted on a cable or board and its subsequent fragile electrical connection. Deflecting any pressure from the connector electrical connections to mechanical components corresponds to the term strain relief. It aims at ensuring a steady and strong electrical connection.
Printed Circuit Board Header Classification
You have already encountered the different types of PCB headers. However, these types of printed circuit board headers fall under specific classes of PCB headers. In having a secure and better circuit connection, PCB headers become instrumental. Additionally, we have already discussed the availability of PCB headers either as female or male versions. But for PCB headers, can fall under the following broad classes.
- Right-angled printed circuit board header
- Screw terminal header
- Multiple rows printed circuit board header
Applications of Printed Circuit Board Headers
- The PCB headers get applied in LCD circuit modules, Xbee circuit modules, etc.
- The PCB headers also get deployed to evaluate PCB boards and other crucial printed circuit board types.
- It also becomes pivotal in the computer’s power supply system, especially one that links to your floppy drive.
- PCB headers also prove pivotal in motherboards and ensuring proper functionality.
Electrical Specifications of a PCB Header
- A 3 A continuous current rating
- A 5000 MOhmms min insulation resistance
- A -65 to a +125 degree Celsius operating temperature
However, please note that these ratings can end up changing based on the specific manufacturer and your PCB requirements as well.
If you want a PCB header, it becomes crucial to understand what it implies, its importance in a PCB, and where you can get one. The article details plenty of crucial aspects relevant to understanding a PCB header that I hope will prove useful to your circuit design needs. If you want to procure one, RayMing PCB and Assembly can also source and provide this crucial component for you.