any bode can help me about bidirectional dc current sensing with 358 or 324 op amp ? need its output read form mcu. i was try on Google , but not get it .
i'm trying to do an amp meter with a shunt
I have need to read 50 amp DC. for inverter.
1- as on load ( when inverter on , now charging
off)
2- as on charging mode (now invereter
off ,charging on )
these reading read with 1 ADC .
not 2 ADC.
Not sure if it's one or two sensors, but I would not bother with the shunt approach. Use one of these: https://www.pololu.com/product/2199 The output is inherently isolated.
Not sure if it's one or two sensors, but I would not bother with the shunt approach. Use one of these: https://www.pololu.com/product/2199 The output is inherently isolated.
You're making it far too complicated - use a single opamp and bias it so zero current gives half voltage out, current one way will increase the voltage, current the other way will decrease it - one opamp, one adc, a little simple maths, no problem.
You're making it far too complicated - use a single opamp and bias it so zero current gives half voltage out, current one way will increase the voltage, current the other way will decrease it - one opamp, one adc, a little simple maths, no problem.
yes sir too complicated ,
when i usedit one by one ADC .is work fine
but when Add 2 pc IN 4148 diAod . its droped 0.350 volt on o\p terminal.
i use reff doc those AN1521 form microchip .
in this Atchment show only 1 part
Assume: ADC range is 0 to 1V
Assume:Vref=1V
Want to measure +/- current.
(I think a gain of 100 is too large but)
R12 and R13 (2k and 2k) look like a 1k to 1/2 of Vref. (1k to 0.5V)
The amp has a gain of 100x. So a +/- 5mV signal will make a +/-500mV signal centered around 0.5V.
Assume: ADC range is 0 to 1V
Assume:Vref=1V
Want to measure +/- current.
(I think a gain of 100 is too large but)
R12 and R13 (2k and 2k) look like a 1k to 1/2 of Vref. (1k to 0.5V)
The amp has a gain of 100x. So a +/- 5mV signal will make a +/-500mV signal centered around 0.5V. View attachment 89230
The output of the opamp will be a negative voltage in the cct you provided. The positive reference voltage should be connected to the +ve input of the opamp.
I think it's better to do it as shown in the following circuit. Zero amps gives ~2.5V out, -50 A --> 5 V out and +50 A --> 0 V out. Gain can be changed by changing R1.
I think it's better to do it as shown in the following circuit. Zero amps gives ~2.5V out, -50 A --> 5 V out and +50 A --> 0 V out. Gain can be changed by changing R1. View attachment 89239
whats the EQUATION of this sch ?
Also tell me About v1 & v2. v1 is those voltage , which Are develop here by current flow ?
v2 is reff voltage . I'm right ?