Hello everyone.
I want to build a current source for low currents, 1-5mA. I've searched for something easy and found the LM234. In his datasheet there are an application to build an independent temperature current source (pg 6). I've simulated in Pspice with this model for the LM334, and work. (see atached images)
So i've decided to try implement. (see atached images)
VCC it's 5V.
But when i've mounted in a protoboard, don't work. If i change the load, current across the load (potentiometer) change. Anyone know what i misunderstanding?
I want to build a current source for low currents, 1-5mA. I've searched for something easy and found the LM234. In his datasheet there are an application to build an independent temperature current source (pg 6). I've simulated in Pspice with this model for the LM334, and work. (see atached images)
So i've decided to try implement. (see atached images)
VCC it's 5V.
But when i've mounted in a protoboard, don't work. If i change the load, current across the load (potentiometer) change. Anyone know what i misunderstanding?
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