Triple slope A=D converter system - has first and second integrations occurring in same direction and uses counting interrupt gate

摘要

The triple-slope A/D converter needs no up/down counter and is therefore cheap to make. If however and up/down counter is employed a level detector can be used whose response delay is greater than one clock period. The first and second integrations take place in the same direction the two reference voltages have the same polarity and their end is detector by the same level detector. A gate (21) is provided to interrupt the counting of a given number of clock pulses to fix the start of the second integration period. A second reference voltage is applied to the level detector in the third integration period during the interruption to counting.