The basic algorithm used in the successive approximation (initially called feedback subtraction) ADC conversion process can be traced back to the 1500s relating to the solution of a certain mathematical puzzle regarding the determination of an unknown weight by a minimal sequence of weighing operations (Reference 1). In this problem, as stated, the object is to determine the least number of weights which would serve to weigh an integral number of pounds from 1 lb to 40 lb using a balance scale. One solution put forth by the mathematician Tartaglia in 1556, was to use the series of weights 1 lb, 2 lb, 4 lb, 8 lb, 16 lb, and 32 lb. The proposed weighing algorithm is the same as used in modern successive approximation ADCs. (It should be noted that this solution will actually measure unknown weights up to 63 lb rather than 40 lb as stated in the problem). The algorithm is shown in Figure 4 where the unknown weight is 45 lbs. The balance scale analogy is used to demonstrate the algorithm.