A Study on the Testing of the 555-Chip Trigger Level

The 555-chip is of a multi-purpose integrated circuit chip which operation depends mainly on the changeover of the triggered high- and low level on the output terminal. This paper carries out a study on the new method for testing of the 555-chip trigger level, in which a single chip is adopted to control the DAC. Adjustably continued varying voltage can thus be put out to accurately measure up the trigger level on the low- and high trigger terminals that lead to the turnover of the 555-chip. A reasonable classification of the 555-chip is made according to different results of measurement. The 555-chip of the same class shall be adopted in the same line in order for achieving an effect in consistency and improving the quality of control. This paper provides a brand new testing method that accomplishes a rapid and highly efficient measurement of the 555-chip trigger level in bulk.