Broadly speaking, board to board connectors are manufactured in the following types:
GCT board to board connectors are available in through hole (TH) and Surface Mount (SMT) variants.
Locating pegs (also referred to as locating posts, alignment pins or board locks) are used to assist alignment of connectors to the PCB. Locating pegs are particularly useful when using surface mount components.
Pitch refers to the spacing between individual pins. There are numerous considerations the hardware designer must balance in choosing the correct connector pitch:
Space constraint - The smaller the pitch, the smaller the connector. Generally using smaller pitches allows lower connector profiles and thus lower printed circuit board stacking profiles. However, GCT offer numerous low profile connector options across all pitches.
Current carrying capacity - the smaller the header pin size the lower the current carrying capacity.
Other physical constraints - does the range offer the connector types to achieve the design you require? e.g. there are sixty seven 2.54mm connector options and nineteen 1.00mm options, so depending on your design you're more likely to find a physical solution in the numerically larger ranges. That said, the small ranges cater for the most basic designs, such as PCB's mating in co-planar, right angle and parallel orientations.
GCT board to board connectors are available in the following pitches:
For experienced hardware designers choosing board to board connectors is second nature, for the uninitiated it can be daunting. We offer design support and will help guide you through the options available. If you need help with your board to board connector design, contact GCT. Where required GCT also offer non standard pitches, you can see an example on our custom connector page.
GCT offer headers are receptacles in single, dual, triple and quad row configurations. Single and dual row are popular choices, while triple and quadruple row are offered in a smaller number of pitch and style options.
Dependent on the your application, PCB's can be oriented in a variety of ways:
In order to cater for differing PCB orientations, different board to board connector orientations have been developed to suit. In most application a pin header and socket would be used as a pair ro simplify assembly and allow disconnection/reconnection (mating cycle) as required.
To achieve a connection between a pair of parallel PCB's only one part combination can be used:
To achieve a connection between a pair of horizontal PCB's only one part combination can be used:
To achieve a connection between a pair of perpendicular PCB's, two combinations could be used:
Here are some examples of board to board pin and contact options.
Post length (also known as post height) is the length of pin above the plastic insulator that mates with the socket (only applicable to pin headers):
Tail length is the length of pin below the insulator that is used to solder to the PCB. Tail length is applicable to pin headers and sockets but only in through hole format:
Post/pin size is the cross section of the conductor measured in mm².
Each different pitch has a different post size:
Kinked pins (also known as locking leads) are used as a method of fastening a through hole pin header or socket to a PCB prior to soldering.
Kinked pins are particularly useful when using tall components and/or wave soldering process that may cause the connector to move out of position before it can be soldered in place.
Example of a kinked PCB header pin:
GCT manufactures 4 types of contacts for use in sockets:
Please see individual datasheets for contact types used in each range.
Plastic insulators are used for the following purposes:
GCT board to board connector insulators are Nylon 6T or LCP (Liquid Crystal polymer), and are produced with complex and highly accurate tools. Below are some of the features of these insulator materials:
A good starting point when calculating PCB connector stacking is to calcualte the board to board connector height. This is measured from the printed circuit board face to its highest insulator point above the PCB is known as its profile. See some examples below:
When an exact distance is required between PCB's it is common to use a stacking pin header and female socket arrangement.
For example, if a PCB separation distance of 20mm is required a 5.00mm profile socket and 15mm stacking height elevated pin header could be used. This is only an example as in the GCT board to board connector range we have connectors with a variety of insulator profiles, depending on connector pitch.
An alternative to stacking headers. Why customers choose stacking sockets:
Also known as pass through, allows mating with a pin header from the underside of the PCB rather than the top side.
When bottom entry sockets are used, holes are drilled in the PCB to allow the pin header to pass through.
Example of a bottom entry, SMT socket PCB layout:
Customers choose bottom entry sockets to reduce distance between stacked PCB's, or to allow use of a single sided PCB.
In order to select the correct header mating pin length customers must provide PCB thickness (for example 1.6mm/.062"), the PCB thickness must be taken into account to calculate the total distance to the mating point. GCT receptacle drawings show the mating points.
This section covers connector contact material and plating within GCT's board to board connector range. Core header pins & receptacle contacts are manufactured using high quality copper alloy, this material is cost effective, easy to manufacture with good electrical properties.
Metal plating layers are added to the core pin or contact to allow or improve:
All pins and contacts are under-plated with a layer of nickel to:
Finish plating is available in variants of gold or RoHS compliant tin
GCTs range of board to board connectors are available in a variety of packaging options as standard:
Custom packaging is available. For example, through hole connectors in tape and reel packaging for paste in hole applications. Contact us to request a custom packaging option.
See images below for some packaging examples. More information is available on specific product datasheets.
GCT's SMT headers offers customizable mating pin lengths and each series has a choice of multiple numbers of circuits. This adds up to thousands of individual part number combinations per connector series.
It's important for connectors to be packaged within correctly sized cavities in the tape and reel carrier strip, the correct height, width and depth cavity to house the header and cap keeps parts in a secure and consistent position during transportation. Once connectors reach the production line they should be presented for pick and place process in a consistent and stable manner.
GCT offer a range of custom Tape and reel carrier strip packaging cavities. One T&R cavity can accept more than one circuit size, however, given the number of connector variations not all cavities are tooled.
The examples below show headers, SMT sockets are also offered in multiple cavity sizes, the height and footprint of sockets may often be fixed, but width is a custom variable dependent on circuit size.
Customers may also choose T&R packaging for thru hole component used in a paste in hole production process.
Contact your local GCT sales office to discuss your PCB connector packaging requirements.
GCT's range of polarized connectors for board to board applications offer a variety of options. Customers may choose from a range of pitch sizes, each having their own method of assuring that mating headers and sockets may only be plugged together in the correct way. All options include shrouding and keying designed into insulator on the male and female mating halves.
Why use polarized connectors?
The keyed and molded BC060 & BC061 offer a tiny, surface mount, polarized connector option for parallel PCB mating configurations, available in 10-30 circuits.
Polarization is achieved by a different sized cut out at each end of the male header, the female connector include two end pieces which mate perfectly with the header cut outs. In addition there is an offset sideway key. There are options in this range to mate PCB's in parallel and right tangle orientation. An elevated stacker header offers other design choices for stacking polarization.
A Central bump system similar to traditional IDC connectors prevents header and socket being mismated. Headers are keyed while the receptacle has a sidewall bump.