A POGO PIN or SPRING-LOADED CONNECTOR is a type of electrical connector mechanism that is used in many modern electronic applications and the electronics testing industry. They are used for their improved durability over other electrical contacts and the resilience of their electrical connection to mechanical shock and vibration.
The name POGO PIN comes from the pin’s resemblance to a pogo stick – the integrated helical spring in the pin applies a constant normal force against the back of the mating receptacle or contact plate, counteracting any unwanted movement which might otherwise cause an intermittent connection. This helical spring makes POGO PINS unique since most other types of pin mechanisms use a cantilever spring or expansion sleeve.
A complete connection path requires a mating receptacle for the pin to engage, which is termed a target or land. A POGO target consists of a flat or concave metal surface, which, unlike the pins, has no moving parts. Targets may be separate components in the complete connector assembly, or in the case of printed circuit boards, simply a plated area of the board.
POGO PIN CONNECTOR is precision parts fabricated with a turning and spinning process which does not require a mold, thus allowing the production of smaller quantities at a lower cost.
A basic POGO PIN (SPRING-LOADED CONNECTOR) consists of 3 main parts: Plunger, Barrel, and Spring. When force is applied to the pin, the spring is compressed and the plunger moves inside the barrel. The shape of the barrel retains the plunger, stopping the spring from pushing it out when the pin is not locked in place.
In the design of electrical contacts, a certain amount of friction is required to hold a connector in place and retain the contact finish. However, high friction is undesirable because it increases stress and wears on the contact springs and housings. Thus, a precise normal force, typically around 1 newton, is required to generate this friction. Since a POGO PINS needs to have a slight gap between the plunger and barrel so that it can slide easily, momentary disconnections can happen when there is vibration or movement. In order to counter this, the plunger usually has a small tilt to ensure a continuous connection
As common in electrical connectors, manufacturers often apply gold plating that improves durability and contact resistance.