- #1

- 238

- 26

- Homework Statement
- I wanted to understand the current amplification circuit

- Relevant Equations
- KCL, KVL equations

I have taken portions of a schematic for amplifying the current I1, this I1 current is the phase current from one of the legs of the inverter. The output vout1 is the amplified voltage, again given to a micro which has internal opamp. Is my circuit understanding correct?

When I give I1 = 10 Amp

Vout1 = 0.1457

Vout2 = 0.03

Amplification factor = 0.145/0.03 = 4.833

--- Operating Point ---

V(n001): 3.3 voltage

V(vout1): 0.145714 voltage

V(vout2): 0.0300002 voltage

I(I1): 10 device_current

I(Rshunt): 10.0001 device_current

I(R3): -7.71428e-005 device_current

I(R2): 6.62338e-005 device_current

I(R1): 0.000143377 device_current

I(V1): -0.000143377 device_current

when I1 = 20 Amp

Vout1 = 0.162857

Vout2 = 0.0600002

Amplification factor = 0.162857/0.0600002= 2.7

--- Operating Point ---

V(n001): 3.3 voltage

V(vout1): 0.162857 voltage

V(vout2): 0.0600002 voltage

I(I1): 20 device_current

I(Rshunt): 20.0001 device_current

I(R3): -6.85714e-005 device_current

I(R2): 7.4026e-005 device_current

I(R1): 0.000142597 device_current

I(V1): -0.000142597 device_current

The amplification factor is not constant, as expected it to be constant. Please advise.

When I give I1 = 10 Amp

Vout1 = 0.1457

Vout2 = 0.03

Amplification factor = 0.145/0.03 = 4.833

--- Operating Point ---

V(n001): 3.3 voltage

V(vout1): 0.145714 voltage

V(vout2): 0.0300002 voltage

I(I1): 10 device_current

I(Rshunt): 10.0001 device_current

I(R3): -7.71428e-005 device_current

I(R2): 6.62338e-005 device_current

I(R1): 0.000143377 device_current

I(V1): -0.000143377 device_current

when I1 = 20 Amp

Vout1 = 0.162857

Vout2 = 0.0600002

Amplification factor = 0.162857/0.0600002= 2.7

--- Operating Point ---

V(n001): 3.3 voltage

V(vout1): 0.162857 voltage

V(vout2): 0.0600002 voltage

I(I1): 20 device_current

I(Rshunt): 20.0001 device_current

I(R3): -6.85714e-005 device_current

I(R2): 7.4026e-005 device_current

I(R1): 0.000142597 device_current

I(V1): -0.000142597 device_current

The amplification factor is not constant, as expected it to be constant. Please advise.