| 摘要 |
For checking and detecting errors during the operation of electrical and/or electronic display devices, preferably of so-called segment displays which can be activated cyclically by a decoder stage, a reduction in the previous considerable control complexity for the error detection in such digital systems and display devices is achieved by the fact that an electrical analog actual-value quantity obtained from a common activation of the individual display elements, that is to say, for example, light-emitting diodes, of each digit is compared as an analog value with an analog nominal-value quantity obtained by recoding from the original binary code used for the selective activation. Deviations which are above a predetermined tolerance limit are indicated by an error display/alarm generation. The device suitable for this purpose comprises an electrical device (6) generating the analog actual-value quantity, which can be associated with the activation stage (4) which supplies all individual display elements, in each case forming one joint digit, jointly with an electrical state quantity, usually cyclically with other digits. A recoding device (9) generates the nominal-value quantity from the binary code which, via a corresponding decoder, is used for activating the individual display elements, as analog nominal-value quantity. The comparison can be carried out with the aid of comparators (8), preferably by means of two comparators (8a, 8b). Thus, tolerance limits can be predetermined for upper and lower deviations. <IMAGE>
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