Integrated circuit with test mode, and test configuration for testing an integrated circuit

• US 6,720,785 B2
• Filed: 06/18/2001
• Issued: 04/13/2004
• Est. Priority Date: 06/16/2000
• Status: Expired due to Term

• Current Assignee: ChangXin Memory Technologies, Inc.
• Original Assignee: Infineon Technologies AG
• Inventors: Bette, Alexander
• Primary Examiner(s): Cuneo, Kamand
• Assistant Examiner(s): NGUYEN, TRUNG Q
• Application Number:
  US09/883,822
• Publication Number:
  US 20020008235A1
• Time in Patent Office: 1,030 Days
• Field of Search: 324/73.1, 324/73.R, 324/73.PC, 324/158.1, 324/158.T, 324/754, 324/763, 324/765, 324/766, 371/22.1, 371/22.5, 371/22.6, 371/20, 438/17, 438/18, 714/30, 714/733, 257/136
• US Class Current: 324/762.02
• CPC Class Codes: G01R 31/3185 Reconfiguring for testing, e.g. LSSD, partitioning
• CPC Class Codes: G11C 29/12 Built-in arrangements for testing, e.g. built-in self testing [BIST] or interconnection details
• CPC Class Codes: G11C 29/48 Arrangements in static stores specially adapted for testing by means external to the store, e.g. using direct memory access [DMA] or using auxiliary access paths

Abstract

During a function test on an integrated circuit, the integrated circuit is connected to an automatic test machine. A connection pad provided exclusively just for supplying an additional or programming voltage is connected to a voltage connection of the automatic test machine. A switch that can be switched in the test mode connects the connection pad in order to actuate irreversibly programmable switches. This keeps down the level of complexity for supplying a programming voltage for the switching elements.

Claims

1. An integrated circuit, comprising:

first connection areas each connecting to one of two poles of a supply voltage;

a switch having a first input receiving a test signal for actuating said switch so that said switch is on in a test mode and off during a normal mode, said switch having a second input for receiving an impressed voltage and an output;

a second connection area connected exclusively to said switch and providing the impressed voltage; and

a functional unit having elements which can be irreversibly switched by impressing the impressed voltage, said functional unit having an input connected to said output of said switch for receiving the impressed voltage.

2. The integrated circuit according to claim 1, wherein one of said elements forms a conducting current path in an initial state and forms an unloaded current path when the impressed voltage has been impressed.

3. The integrated circuit according to claim 1, wherein the impressed voltage required for irreversibly switching said elements is different than the supply voltage.

4. The integrated circuit according to claim 3, wherein a magnitude of the impressed voltage is greater than that of the supply voltage.

5. A test configuration, comprising:

an automatic test machine having connections for supplying poles of a supply voltage, further connections for supplying signals containing a plurality of states, and a test connection for supplying an impressed voltage; and

an integrated circuit, containing;

first connection areas connected to said automatic test machine for receiving the poles of the supply voltage;

a switch having a first input for receiving a test signal for actuating said switch so that said switch is on in a test mode and off during a normal mode, said switch having a second input for receiving the test voltage and an output;

a second connection area having a first terminal connected exclusively to said second input of said switch and a second terminal connected to said test connection for receiving the impressed voltage; and

a functional unit having elements which can be irreversibly switched by impressing the impressed voltage, said functional unit having an input connected to said output of said switch for receiving the impressed voltage.