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What kind of comparator is the LM393?
The LM393 is a dual differential comparator; this means that it accepts 2 inputs for comparison. It compares these voltage inputs and determines which is the larger value.
Where is the GND on the LM393 chip?
GND is where the ground wire of the voltage source gets connected to. These 2 terminals complete the power path for the LM393 chip and gives it the power it needs to function.
Is the LM358 a rail to rail op amp?
LM358 is not a rail-to-rail output op-amp, so you should not expect it to produce an output near the positive supply voltage. Unfortunately, the datasheet doesn’t go out of its way to make this obvious. The main clues are:
Why do we need a comparator in a circuit?
Based on this, electronic decisions can be made based on which input is greater and which is smaller. Thus, a comparator is very useful in circuits where we measure levels and want our circuit to act a certain way based on whether the level of an input is greater or smaller than a certain threshold.
What am I doing wrong with this LM393?
I didn’t look up the LM393, but make sure that the open collector output is really with respect to the negative supply, which is ground in your case. Otherwise, Q2 won’t be reliably turned off, or at all. If the output of U1A really isn’t going high, first check that the supply pins are at the expected voltages. You don’t show what voltage VM is.
What is the output voltage of the LM393?
If the output of the 393 is “on” (not pulled to ground through the internal transistor) and you’re measuring the voltage directly on the output, then you’re just measuring the output of a voltage divider made up of R8 and R10. The output voltage would be (VM-0.7)* (1k/ (3k+1k)) = 1.075 volts assuming VM=5V.
What are the voltage inputs on the LM393?
The LM393 has 2 power inputs. These are labeled Vcc and GND. Vcc is where the positive terminal of the voltage supply gets inserted into. This supply voltage can be as high as 36V. GND is where the ground wire of the voltage source gets connected to.
How to use a comparator in Electrical Engineering?
Use the inverting input for your reference. Usually a pair of resistors configured as a voltage divider will give you the reference voltage required. Use a comparitor for comparison. Use an op-amp for amplification. (But don’t use a 741.)
What happens when op amp is greater than noninverting terminal?
If the voltage at the inverting terminal is greater than the voltage at the noninverting terminal, then the output of the op amp will be drawn down to ground, allowing electricity to flow from VCC to ground, turning on the output device.