JP2539860Y2 - Test head - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an object to be measured (hereinafter referred to as D).
The present invention relates to a test head of an LSI tester in which a contact board for transmitting and receiving a test signal and a performance board on which a UT is mounted are connected to a pin electronics board of a signal source via a flexible printed circuit board. Impedance of transmission route of printed circuit board
The present invention relates to a test head in which a dance is matched with the impedance of a signal source provided on a pin electronics board.

[0002]

2. Description of the Related Art An LSI tester transmits and receives test signals via a performance board on which a DUT is mounted and a test head, and measures the characteristics of the DUT. The test signal is transmitted from a driver of a pin electronics board in the test head to a contact pin connected via a cable. The message is transmitted to the moonboard.

[0003]

In such a test head, since the pin electronics board and the contact pins are connected using a cable, the cable is connected to each contact pin by a soldering iron. It had to be connected and the connection work was complicated. Further, since the connection is made by a soldering iron, a problem may occur in the reliability of the solder portion.

The present invention has been made in view of the above points, and is intended to connect a pin electronics board and a contact pin using a flexible printed circuit board. It is an object of the present invention to provide a test head in which the connection operation between a contact pin and a contact pin is simple, high in reliability, and excellent in signal characteristics.

[0005]

In order to achieve the above object, according to the present invention, a test signal of a pin electronics board is provided to a contact pin via a flexible printed circuit board, and the test signal is supplied to a test object. A test head for transmitting and receiving a performance board on which an object is mounted, wherein a mesh-shaped ground pattern is provided via an insulating member on a signal pattern of the flexible printed circuit board to which a test signal is transmitted. And the signal pattern
The impedance of the pin electronics board is matched with the impedance of the pin electronics board.

[0006]

The pin electronics board and the contact pins are connected by a flexible printed board, and the impedance of the signal pattern of the flexible printed board is provided by providing a mesh-shaped ground pattern. To match the impedance.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a main configuration of the test head of the present invention. In the figure, reference numeral 1 denotes a box-shaped test head, on which a plurality of pin electronics boards 2 are provided radially from the center. In the drawing, two pin electronics boards 2 are shown as representatives.

The pin electronics board 2 supplies a test signal to the contact pins 4 via the flexible printed circuit board 3, and exchanges the test signal with a performance board 6 on which the DUT 5 is mounted. The flexible printed circuit board 3 has a mesh-shaped ground pattern for the signal pattern so as to match the impedance of the signal source provided on the pin electronics board 2 (see FIGS. 2 and 3).
Are provided with a predetermined width.

FIG. 2 shows a laminated structure of a flexible printed board, and FIG. 3 shows a configuration diagram of the flexible printed board. The flexible printed circuit board 3 is connected to the signal pattern 3 via the base film 31.
2 and a ground pattern 33 are provided. Each of the signal pattern 32 and the ground pattern 33 is protected by a cover film 34.

The characteristic impedance of the flexible printed circuit board 3 includes the width W and the thickness t of the signal pattern 32, the distance L from the ground pattern 33 to the signal pattern 32, the material, and the like. -Determined by the characteristics of the film 31.

The impedance of the pin electronics board 2
In order to match the impedance of the dance (more than 50Ω) and the signal pattern 32, the signal pattern 32
Or the thickness of the base film 31 may be increased. However, in order to obtain an impedance of 50 Ω or more by making the signal pattern 32 thin, it is impossible to manufacture the flexible cable 3, and it is also necessary to increase the thickness of the base film 31. Since the flexibility of the substrate 3 is lost, it is not preferable for a test head that requires swinging.

For this purpose, a ground pattern 33 is provided in a mesh shape to achieve impedance matching. The signal patterns 321 to 324 are patterns for which impedance matching needs to be performed. A ground pattern 33 is provided in a mesh shape at this portion via the base film 31. Since the signal patterns 325 to 328 do not need impedance matching, the ground pattern 33 is not provided.

FIG. 4 shows a signal pattern width and a ground pattern.
FIG. 9 is a diagram illustrating an example of characteristic impedance of a flexible printed circuit board that changes depending on a relationship with a circuit width. The area ratio of the ground pattern 33 can be freely selected by the ratio of the width wa of the conductor pattern constituting the mesh to the interval wb between the conductor patterns. For example, the width w of the conductor pattern
If a is 0.15 mm and the spacing wb between the conductor patterns is 0.85 mm, the area ratio of the ground pattern is 15%.

In general, since the ground pattern 33 has the same mesh shape in the same flexible cable 3, the impedance of the signal pattern 32 is as follows.
The pattern width W of each signal pattern is changed to match.

For example, if the area ratio of the ground pattern is 35
%, A signal pattern 321 having a pattern width of 0.12 mm can provide an impedance of about 77 Ω and a pattern width of about 77 Ω.
With a signal pattern 322 of 0.17 mm, an impedance of 67Ω can be obtained.

[0016]

As described above in detail, in the test head of the present invention, the connection between the pin electronics board and the contact pins is made by using a flexible printed circuit board and the signal pattern for transmitting the test signal. Since the impedance of the signal source is adjusted to the impedance of the signal source by the ground pattern, the connection operation is simple, the reliability is high, and good signal characteristics can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a main configuration of a test head according to the present invention.

FIG. 2 shows a laminated structure of a flexible printed circuit board.

FIG. 3 shows a configuration diagram of a flexible printed circuit board.

FIG. 4 is a diagram showing an example of a characteristic impedance of a flexible printed circuit board that changes depending on a relationship between a signal pattern width and a ground pattern width.

[Explanation of symbols]

 2 pin electronics board 3 flexible printed circuit board 32 signal pattern 33 ground pattern 4 contact pin

Claims (1)

(57) [Scope of request for utility model registration] 1. A test head for providing a test signal of a pin electronics board to a contact pin via a flexible printed circuit board and transmitting and receiving the test signal to and from a performance board on which a device under test is mounted. ,
A signal pattern on the flexible printed circuit board to which the test signal is transmitted is provided with a mesh-shaped ground pattern provided via an insulating member, and the impedance of the signal pattern is changed to the pin electronics board. A test head characterized by being matched to the impedance of the head.