A-D converter testing circuit and D-A converter testing circuit
US5583502A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1994 |
| Grant date | Dec 10, 1996 |
| Priority date | — |
| Expiry date | Jun 21, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/66
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
There is disclosed an A-D converter testing circuit wherein exclusive-OR gates (13a, 13b) provide the exclusive-OR of the high-order bits (D.sub.1a, D.sub.1b) of the outputs of A-D converters (12a, 12b) and the exclusive-OR of the high-order bits (D.sub.1b, D.sub.1c) of the outputs of A-D converters (12b, 12c), respectively, and an OR gate (13c) provides the logical sum of the outputs of the both gates, which is "L" if all of the bits (D.sub.1a, D.sub.1b, D.sub.1c) are equal. A tri-state buffer (15a) receives the output of the OR gate (13c) at its control end and receives the bit (D.sub.1c) at its input. When all of the A-D converters are normal, all of the bits (D.sub.1a, D.sub.1b, D.sub.1c) are equal and are applied to the output of the tri-state buffer (15a). When one or some of the A-D converters are abnormal, the output of the tri-state buffer (15a) enters a high-impedance state. The A-D converter testing circuit, therefore, rapidly judges whether the A-D converters are defective or non-defective.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.