voltage to current converter (1)

Voltage to current converter in which load resistor RL is floating (not connected to ground). • Vin is applied to the non-inverting input terminal, and the feedback voltage across R1 devices the inverting input terminal. • This circuit is also called as a current – series negative feedback amplifier. Because the feedback voltage across R1 (applied non-inverting terminal) depends on the output current i0 and is in series with the input difference voltage Vid.Writing KVL for the input loop, Voltage Vid=Vf and IB=0, Vi = RLi0 Where io=Vi/RL Input voltage Vin is converted into output current of Vin/RL [Vin -> i0]. In other words, input volt appears across R1. If RL is a precision resistor, the output current (i0 = Vin/R1) will be precisely fixed.