Circuit testing with ring-connected test instrument modules
First Claim
1. A system for controlling one or more test instruments to test one or more integrated circuits, the test instruments being connected to form a communication ring, the system comprising:
- a master clock connected to each test instrument, the master clock being configured to provide a clock signal to the one or more test instruments; and
a controller connected to the communication ring, the controller being configured to align counters of test instruments to derive a common clock time value from the clock signal, the controller being further configured to generate and send data words into the communication ring to carry the data words to each test instrument, the data words including at least one data word specifying a test event to be performed, a common clock time value, and at least one of the test instruments, wherein the at least one of the test instruments is configured to perform the test event at the time specified by the common clock time value.
2 Assignments
0 Petitions
Accused Products
Abstract
Method and apparatus for circuit testing with ring-connected test instrument modules. A system for controlling one or more test instruments to test one or more integrated circuits includes a master clock and a controller. The test instruments are connected to form a communication ring. The master clock is connected to each test instrument and provides a clock signal to the one or more test instruments. The controller is connected to the communication ring and is configured to align counters of test instruments to derive a common clock time value from the clock signal. The controller is further configured to generate and send data words into the communication ring to carry the data words to each test instrument. The data words includes at least one data word specifying a test event to be performed, a common clock time value, and at least one of the test instruments.
-
Citations
29 Claims
-
1. A system for controlling one or more test instruments to test one or more integrated circuits, the test instruments being connected to form a communication ring, the system comprising:
-
a master clock connected to each test instrument, the master clock being configured to provide a clock signal to the one or more test instruments; and
a controller connected to the communication ring, the controller being configured to align counters of test instruments to derive a common clock time value from the clock signal, the controller being further configured to generate and send data words into the communication ring to carry the data words to each test instrument, the data words including at least one data word specifying a test event to be performed, a common clock time value, and at least one of the test instruments, wherein the at least one of the test instruments is configured to perform the test event at the time specified by the common clock time value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
-
-
23. A data and control signal distribution subsystem for an automatic circuit test system having test instruments for performing tests on a electrical circuit, the subsystem comprising:
-
a communication ring for coupling test instruments in the system to each other in a daisy chain fashion, where the communication ring is configured to connect to each test instrument through a single input port and a single output port;
a master clock circuit providing a master clock signal; and
a dedicated clock signal path between each test instrument in the test system and the master clock circuit, the dedicated clock signal paths together distributing the master clock signal to all test instruments in parallel;
wherein the communication ring is the exclusive path for test instruments in the test system to send synchronization signals and command signals to one another during a performance of a test, and the master clock signal received through a dedicated signal path is the exclusive global clock signal provided to test instruments in the test system.
-
-
24. A computer program product, tangibly stored on machine-readable medium, for controlling one or more modules that are configured to test one or more integrated circuits in accordance with a test process, the product comprising instructions to cause a processor to perform functions comprising:
-
identify at least one of the one or more modules that is participating in the test process;
identify a test thread among independent test threads for the identified instrument, the test thread comprising instructions for generating data words to be sent to other modules; and
send the test thread to the identified instrument. - View Dependent Claims (25, 26)
-
-
27. A method for controlling and synchronizing one or more test instruments connected in a communication ring to test an electrical circuit, the method comprising:
-
setting and maintaining synchronization of an internal time register of each test instrument to a common clock cycle by using a global clock signal of a master clock, the common clock cycle providing common clock time values for scheduling test events;
inserting bus words into the communication ring to carry the bus words to each of the test instruments, the inserted bus words including at least one bus word specifying a scheduled common clock time value for performing a test event by a target test instrument; and
reading, by the target test instrument, the at least one bus word and using the scheduled common clock time value and the common clock cycle value in the internal time register of the target test instrument to determine when to perform the test event. - View Dependent Claims (28, 29)
-
Specification