# Summing amp inputs for an ADC

Joined Nov 13, 2015
7
Hi, I am currently trying to create a system of a ADC including a summing amp along with latches. But my question is that what are the two or more inputs of the summing amp if i'm getting a single signal output? Also another question that i need answering is how do i use differential amplifiers to create two outputs from one single input? This was supposed to include bilateral switches but i'm unsure. Here is a picture of my block diagram. Help.

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#### crutschow

Joined Mar 14, 2008
32,918
If you don't have two signals to sum then you don't need a summing amp.
Differential amps have a differential input (2 inputs), normally not two outputs.
Why do you need two outputs? A single output can go to more than one place.
What would the bilaterial switch do? Who told you to include those?

You seem to be putting together random technical terms without understanding what you are trying to do.
If you can explain the purpose of the circuit and all the blocks then we can better help.

This sounds like homework.

Joined Nov 13, 2015
7
If you don't have two signals to sum then you don't need a summing amp.
Differential amps have a differential input (2 inputs), normally not two outputs.
Why do you need two outputs? A single output can go to more than one place.
What would the bilaterial switch do? Who told you to include those?

You seem to be putting together random technical terms without understanding what you are trying to do.
If you can explain the purpose of the circuit and all the blocks then we can better help.

This sounds like homework.
Well my circuit is supposed to be that when the temperature gets to a certain point to a degree the fan will turn on. Anything lower the heater turns on. They can't both be on so that's why I use the differential amplifier. Also the 7 segs are to display the temperature. Does that help

#### GopherT

Joined Nov 23, 2012
8,009

You could do this quite easily with an ILC7107 and ADC with direct output to 7-seg display. and an LM35 or LM34 Temp chip (reads degrees as millivolts).

Add a comparitor to the temp chip to get your switching. Everything with three chips.

Joined Nov 13, 2015
7

You could do this quite easily with an ILC7107 and ADC with direct output to 7-seg display. and an LM35 or LM34 Temp chip (reads degrees as millivolts).

Add a comparitor to the temp chip to get your switching. Everything with three chips.
However this circuit is supposed to have 5 subsystems where I can do 2 tests on each one

#### GopherT

Joined Nov 23, 2012
8,009
However this circuit is supposed to have 5 subsystems where I can do 2 tests on each one
Ah! Nice to know Rube Goldberg is still influencing system design.

#### crutschow

Joined Mar 14, 2008
32,918
Where is it stated that you need 5 subsystems?
If you post the exact requirements, then we can better help you.
Otherwise we're just going in circles.