Analog-to-digital converters

Claim 1

IN INFORMATION TRANSLATING APPARATUS FOR CONVERTING AN INPUT SIGNAL INTO DIGITAL FORM, THE APPARATUS BEING OF THE TYPE HAVING: A REVERSIBLE COUNTER; A CONVERTER CONNECTED TO THE COUNTER FOR CONTINUOUSLY CONVERTING THE DIGITAL COUNT OF THE COUNTER TO AN ANALOG SIGNAL; A COMPARATOR FOR COMPARING THE INPUT SIGNAL WITH THE ANALOG SIGNAL; AND CLOCK MEANS FOR CAUSING THE COMPARATOR TO INTERMITTENTLY COMPARE THE INPUT SIGNAL AND THE ANALOG SIGNAL AND PROVIDE AN OUTPUT CAUSING THE COUNTER TO ALTER ITS COUNT IN THE DIRECTION EQUALIZING THE COMPARED SIGNALS; THE IMPROVEMENT WHEREIN THE CONVERTER EMPLOYS A SOURCE OF A FIXED REFERENCE VOLTAGE COUPLED TO A DIGITAL ATTENUATOR, THE ATTENUATOR CAUSING THE REFERENCE VOLTAGE TO BE ATTENUATED IN ACCORDANCE WITH THE COUNT IN THE REVERSIBLE COUNTER TO PROVIDE THE ANALOG SIGNAL; AND MEANS FOR DIFFERENTIATING THE INPUT SIGNAL AND COMBINING THE DIFFERENTIATED SIGNAL WITH THE REFERENCE VOLTAGE TO MODIFY THE VALUE OF THE REFERENCE VOLTAGE APPLIED TO THE DIGITAL ATTENUATOR.