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Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:03.38,Default,,0000,0000,0000,,>> Now, let's review what an inverting summer does.
Dialogue: 0,0:00:03.38,0:00:07.58,Default,,0000,0000,0000,,We can start with the inverting amplifier shown here and then add on
Dialogue: 0,0:00:07.58,0:00:14.31,Default,,0000,0000,0000,,an additional voltage source, which has its own resistance and its own voltage.
Dialogue: 0,0:00:14.31,0:00:18.63,Default,,0000,0000,0000,,Then, what's going to happen is Vo is going to be the combination of
Dialogue: 0,0:00:18.63,0:00:25.47,Default,,0000,0000,0000,,these two voltages, as shown here.
Dialogue: 0,0:00:25.47,0:00:29.28,Default,,0000,0000,0000,,As with all of our op-amp circuits,
Dialogue: 0,0:00:29.28,0:00:35.85,Default,,0000,0000,0000,,the Vo is limited between the two power supply voltages as always.
Dialogue: 0,0:00:35.85,0:00:42.54,Default,,0000,0000,0000,,We can look at this circuit as having two separate gains A and B,
Dialogue: 0,0:00:42.54,0:00:44.25,Default,,0000,0000,0000,,or minus A and minus B.
Dialogue: 0,0:00:44.25,0:00:51.06,Default,,0000,0000,0000,,And then, what we do is bring in Vs1 and multiply it by minus A,
Dialogue: 0,0:00:51.06,0:00:56.25,Default,,0000,0000,0000,,bring in Vs2 and multiply that by minus B,
Dialogue: 0,0:00:56.25,0:00:58.54,Default,,0000,0000,0000,,and bring the two of these together and add them,
Dialogue: 0,0:00:58.54,0:00:59.90,Default,,0000,0000,0000,,that's the summer part.
Dialogue: 0,0:00:59.90,0:01:01.92,Default,,0000,0000,0000,,That gives us V out.
Dialogue: 0,0:01:01.92,0:01:05.49,Default,,0000,0000,0000,,So, that's how an inverting summer works.