DC Millivoltimeter

Parts
List: |
Component: |
Value: |
Datasheet: |
Qty: |
Resistor |
1M |
Not Available |
01 |
Resistor |
4.7K |
Not Available |
01 |
Resistor |
1K |
Not Available |
02 |
Resistor |
10K Pot |
Not Available |
01 |
IC |
LF356 |
Not Available |
01 |
Description: An LF356 op amp is used as a gain amplifier with the output taken across R5. When a full-scale current of 1 mA is flowing through the meter, exactly 1 V appears across R5 (should be 1% tolerance or better). This is fed back to R2 to the summing junction of IC1 (a full-scale produces 1uA). This offsets the current through R1. R1 has a value of 1 M ohm/V which is used to zero the meter. R4 provides some overcurrent protection for the meter.
Made Clean by: Diognes The Fox