analogue LED display

9-38 — elektor september 1981 analogue LED display The UAA 170 IC differs from its UAA 180 counterpart in that it presents a dot display rather than a row (or bar). In other words, up to two LEDs light simultaneously, which cuts down the circuit"s current consumption consider- ably. The three inputs at pins 11 ... 13 (see figure 1) are of vital importance. Whereas pin 11 acts as an input for the voltage being measured, the reference voltage at pins 12 and 13 determine the upper and lower thresholds of the measurement range and are adjustable from 0 to 6 volts. Using, for instance, the bath ther- mometer circuit published in December 1980, the lower reference voltage at analogue LED display using the UAA 170 IC 1 18 V A 15 V ® IC1 can be adjusted between 0 and 5.2 V with the aid of P1. The con- nection for the upper reference voltage... (pin 13) is linked to pin 14 and is there- fore fixed at 5.2 V. By slightly modifying the bath ther- mometer circuit the circuit can be converte...