Method for testing an integrated circuit with an external potential applied to a signal output pin
First Claim
1. A method of testing an integrated circuit comprising the steps:
- a) providing at least one output signal generated by a circuit unit of said integrated circuit to at least one signal output pin of said integrated circuit during a normal operating mode;
b) externally applying an externally applied potential to at least one selected output pin among said at least one signal output pin;
c) evaluating a potential value of said externally applied potential;
d) dependent on and responsive to a result of said evaluating, switching from said normal operating mode into a test mode; and
e) during said test mode, generating in said circuit unit at least one test signal that is to be tested, and providing said at least one test signal to at least one chosen output pin among said at least one signal output pin.
4 Assignments
0 Petitions
Accused Products
Abstract
In previously known methods for testing internal signals of an integrated circuit, additional output pins were required which, in general, were linked to additional measuring pads within the integrated circuit.
In the new method, the circuit functions are tested by using the output pins at which the output signal is present during normal operation of the integrated circuit. By means of a simple, external connection, with which a defined voltage value is set at the signal output, the integrated circuit is switched by means of an integrated control unit into a test mode in which it applies selected signals, which are to be tested, at the signal output. There is no need for additional internal measuring pads or additional output pins.
20 Citations
16 Claims
-
1. A method of testing an integrated circuit comprising the steps:
-
a) providing at least one output signal generated by a circuit unit of said integrated circuit to at least one signal output pin of said integrated circuit during a normal operating mode;
b) externally applying an externally applied potential to at least one selected output pin among said at least one signal output pin;
c) evaluating a potential value of said externally applied potential;
d) dependent on and responsive to a result of said evaluating, switching from said normal operating mode into a test mode; and
e) during said test mode, generating in said circuit unit at least one test signal that is to be tested, and providing said at least one test signal to at least one chosen output pin among said at least one signal output pin. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
Specification