GB2527790A

GB2527790A - Testing device

Info

Publication number: GB2527790A
Application number: GB1411779.0A
Authority: GB
Inventors: Graham Winter; Steven Cudbertson
Original assignee: Linwave Technology Ltd
Current assignee: Linwave Technology Ltd
Priority date: 2014-07-02
Filing date: 2014-07-02
Publication date: 2016-01-06
Anticipated expiration: 2034-07-02
Also published as: GB2527790B; GB201411779D0

Abstract

A jig for use in positioning and holding electronic components during testing comprises an electronic circuit board 2 mounted on a support 4 having signal input/output coaxial microwave cable connectors 6 for connection to electronic test apparatus. The upper surface of the board has a recess 8 in which to receive an electrical component 32 to be tested, and a cap 16 is locatable on the base in contact with the component. A clamp 22 presses the cap on to the component with a pre-determined pressure, the clamp comprising a structure extending over the cap and provided with magnetic means for releasably holding the structure to the base and at least one spring-loaded pressure pad 28 mounted beneath the structure for engaging and pressing the cap.

Description

TESTING DEVICE

Field of the Invention

This invention relates to apparatus for use in positioning and holding electronic components during testing.

Background to the Invention

In the testing of electronic devices such as high-power amplifiers for use in microwave applications and presented as a chip or a packaged component it is necessary to make temporary electrical connections between the amplifier and test apparatus. These connections cannot be soldered connections, since this would render the component unusable after testing, so it is necessary to make the connections by pressure contacts to the relevant conductive pads or leads on the chip or package. Because variations in impedance may arise in making pressure contacts, which would adversely affect the accuracy of the tests, it is necessary to mount the chip or package for testing in a consistent and reproducible manner. Excessive pressure on the chip or package could result in damage.

Accurate alignment of the chip or package in the test apparatus is critical, not only to ensure that the correct electrical connections are made, but also to ensure that pressure is exerted on the connection points only, to avoid risk of damage.

Summary of the Invention

Accordingly, the present invention provides a jig for use in positioning and holding electronic components during testing, comprising a base having a plurality of electrical contacts connected to signal input/output connection means for connection to electronic test apparatus, the base being adapted to receive a component to be tested, a cap locatable on the base in contact with the component, and a clamp for pressing the cap on to the component with a pre-determined pressure, the clamp comprising a structure extending over the cap and provided with magnetic means for releasably holding the structure to the base, and at least one spring-loaded pressure pad mounted beneath the structure for engaging and pressing the cap.

The cap may comprise electrical contact pads on the underside thereof to establish electrical contact with electrical contacts on the upper surface of the electrical component to be tested, the contact pads being in turn in electrical connection with contacts provided around the periphery of the cap and engage-able with corresponding contact pads on the base when the cap is positioned over the component on the base. Component grounding is essential for FIF per-formance, requiring continuity of the ground connection throughout. The bottom ground of the component has to be connected directly to the ground of the jig.

This particular arrangement not only maintains ground continuity, but also mm- imises the inductance to ground and replicates how the component would typi-cally be used in a system.

The cap may be located in a fixed position on the base by means of lo-cating posts projecting downwards from the cap to engage with correspondingly shaped and positioned sockets in the base. It will be appreciated that the re-verse arrangement could also be employed, with the posts projecting from the base and received into sockets in the periphery of the cap.

The clamp structure may similarly be located on the base by means of posts and corresponding sockets to ensure accurate positioning.

The invention also provides an electronic component-testing apparatus comprising a jig according to the invention connected to test signal generating and analysis circuitry.

Brief Description of the Drawings

In the drawings, which illustrate an exemplary embodiment of the inven-tion: Figure 1 is an exploded perspective view of the component-receiving part of a testing apparatus; Figure 2 is an exploded side elevation; and Figure 3 is a wire-frame end elevation.

Detailed Description of the Illustrated Embodiment

Referring to the drawings, the test jig comprises a base 1 consisting of an electronic circuit board 2 mounted on a support 4 and having signal input and output connectors 6 in the form of coaxial microwave cable connectors mounted on the board 2 and electrically connected to circuit elements thereon.

The upper surface of the board 2 has a recess 8 shaped and dimension to re- ceive an electrical component to be tested, for example a high-power micro-wave amplifier. The recess contains electrical contacts corresponding to the external contacts on the amplifier and connected to the signal input and output connectors 6 via circuit elements on the board 2. A pair of circular sockets 10 is provided adjacent each end of the recess 8 and outwardly of these at each end is provided a magnet 12 with a socket 14 at each side thereof. A cap 16 has two pairs of downwardly-projecting posts 18 on the underside thereof and four depressions 20 on the uppermost surface, two at each end.

A clamping member 22 is configured with posts 24 projecting downward- ly therefrom at each end in positions corresponding with the sockets 14 and in-cludes magnets mounted within the member at locations corresponding with the magnets 12, but with opposed poles to those magnets to attract them together.

An opening 26 (Figure 3) in the clamping member 22 receives the cap therein and includes two pairs of downwardly-projecting sprung pins 28 engageable in the depressions 20 of the cap 16 when the cap is located within the opening 26, the sprung pins 28 being configured to apply to the upper surface of the cap 16 a uniform pressure across the cap so that, in turn, the cap applies to the ampli-fier sufficient pressure to ensure good electrical contact with the contacts in the recess 8.

In use, a thin sheet 30 of an elastomeric material containing dispersed metal particles and arranged to be locally conductive where compressed is lo-cated in the recess 8 between the contacts therein and the amplifier, to ensure full electrical contact is guaranteed between the amplifier and the test appa-ratus. The amplifier 32 is positioned in the recess 8 and the cap 16 positioned over it, with the posts 18 located in the sockets 10. The clamping member 22 is then located over the cap 16, with the posts 24 located in the socketsl 4. The magnetic attraction between the magnets in the clamping member 22 and the pads 12 holds the clamping member firmly in position and ensures that the sprung pins 28 exert a consistent force on the cap 16 and therefore on the am-plifier 32. There is thus no risk of an excessive and potentially damaging force being applied, or of insufficient force to ensure a satisfactory electrical contact being achieved.

Claims

CLAIMS1. A jig for use in positioning and holding electronic components dur-ing testing, comprising a base having a plurality of electrical contacts connected to signal input/output connection means for connection to electronic test appa- ratus, the base being adapted to receive a component to be tested, a cap locat-able on the base in contact with the component, and a clamp for pressing the cap on to the component with a pre-determined pressure, the clamp comprising a structure extending over the cap and provided with magnetic means for re- leasably holding the structure to the base, and at least one spring-loaded pres-sure pad mounted beneath the structure for engaging and pressing the cap.
2. A jig according to Claim 1, wherein the cap comprises electrical contact pads on the underside thereof to establish electrical contact with electri-cal contacts on the upper surface of the electrical component to be tested, the contact pads being in turn in electrical connection with contacts provided around the periphery of the cap and engageable with corresponding contact pads on the base when the cap is positioned over the component on the base.
3. A jig according to Claim 1 or 2, wherein the cap is located in a fixed position on the base by means of locating posts projecting downwards from the cap to engage with correspondingly shaped and positioned sockets in the base.
4. A jig according to Claim 1 or 2, wherein the cap is located in a fixed position on the base by means of locating posts projecting upwards from the base to engage with correspondingly shaped and positioned sockets in the cap.
5. A jig according to any preceding claim, wherein the clamp struc-ture cap is located in a fixed position on the base by means of locating posts projecting downwards from the structure to engage with correspondingly shaped and positioned sockets in the base.
6. A jig according to any of Claims 1 to 4, wherein the clamp struc- ture is located in a fixed position on the base by means of locating posts pro- jecting upwards from the base to engage with correspondingly shaped and posi-tioned sockets in the clamp structure.
7. A jig for use in positioning and holding electronic components dur-ing testing, substantially as described with reference to, and/or as shown in, the drawings.
8. An electronic component-testing apparatus comprising a jig ac-cording to any preceding claim connected to test signal generating and analysis circuitry.