I plan to use AD527x for a project where the absolute resistor tolerance is a key parameter.
I got confused on the device DS. For the resistor performance mode DS tells "...code = half scale, RWA = 10 kΩ ± 100 Ω. See Table 2, Table 3, Table 5, and Table 6 to verify which codes achieve ±1% resistor tolerance."
Table 2 says that the 1% code range is for 2.7<Vdd<5.5V "From 0x0BE to 0x3FF" This is not the half range.
DS later says, "Rheostat Operation—1% Resistor Tolerance The nominal resistance between Terminal W and Terminal A, RWA, is 20 kΩ, 50 kΩ, or 100 kΩ and has 1024-/256-tap points accessed by the wiper terminal. " The formula uses RWA to calculate the actual value.
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