# Opamp which works with 5 V input

Can an IC 741 op amp can be used with an input voltage of +5 and -5 V? If not so, what are the commonly used opamps that can be used 5 to 12 V?

Yes you can use a 741 opamp with a voltage at the inputs between -5 V and + 5 V as long as you give it a supply voltage of at least - 8 V and + 8 V (this is my guess, the 741 has a guaranteed +/- 12V input voltage range when a +/- 15 V supply is used, I re-used that 3 V margin (15 V - 12 V) to get to +/- 8 V) note that that is a symmetrical supply voltage, not a single 5V or 12 V supply.

You should read "Reasons not to use a 741 op-amp?" some alternatives are suggested there.

You can use an opamp with a single 5 V supply and have an input voltage of - 5 V, not at the input of the opamp but at the input of the circuit. The limitations of the opamp you use are related to limitations of the circuit design but they are not the same.

For example, suppose I have an opamp which has a limited input voltage of for example 2 V to 3 V. With that opamp I can still design a circuit that can handle a 0 V to 5 V input voltage. It only relies on how I use the opamp.

I also recommend you read "Opamps for everyone"

Some of the other answers here draw conclusions from the Maximum Ratings and the Recommended Operating Conditions. Actually these numbers are completely irrelevant. What is relevant is the Input voltage range, source: The TI datasheet.

Note how this is a table with Electrical Characteristics

The Input voltage range is specified to typically be +/- 13 V but it has a (guaranteed) minimum of +/- 12 V. In a commercial (mass produced) design you would use this +/- 12 V as that you can rely on. The +/- 13 V cannot be relied upon. Also very important: note (1) under the table, this lists the operating conditions which must be applied to get the values listed in the table. Important here is the +/- 15 V supply as the Input Voltage Range is very dependent on the supply voltage that is used.

Yep, reading (and understanding) a chip's specification isn't easy :-)

• Feel like this is a good but incomplete answer as the UA741 does have a +5V and -5V recommended supply voltage. Without knowing which 741 opamp is being used or if he needs full rail to rail output or "something close to 5v" we can't for sure say that he needs at least -10 to 10v supply voltage. – Remco Vink Nov 14 '18 at 9:02
• @RemcoVink Indeed the question isn't detailed enough to answer properly. So my +/- 10 V supply is just an example of what could be needed (I changed it to +/- 8 V which is also an assumption). But the recommended supply voltage of +/- 5 V supply is irrelevant as that will not give a +/- 5 V input range on a 741 as it does not have rail-to-rail inputs. You need to look at the Input Voltage Range. – Bimpelrekkie Nov 14 '18 at 9:20

All of this information about IC's can be found in the datasheet. In this case look for the Recommended Operating Conditions. You will find the following

The recommended operating conditions are between +15 and -15V. This does not mean that you can not power it with a lower supply voltage in this case.

If we look at the Absolute Max operating conditions. You will see that there is no lower limit boundary defined. So the device won't be damaged for using lower voltages and it even has a remark about powering it with lower voltages. However there is always a catch to everything. The datasheet defines the following (5) For supply voltages less than ±15 V, the absolute maximum input voltage is equal to the supply voltage This means that if you power the Vsupply+ with 5V and the Vsupply- with -5V your input signal can not exceed this range!

EDIT

The UA741 even shows +5V -5V as the minimum for recommended operating conditions.

TLDR: Yes +-5V will probably work, Yes you will limit the Vrange of your input signal, Yes there are plenty of "newer" Opamps with +-5V as their Recommended Operating Condition but thats a product request which are not answered on the site.

• Recommended operating conditions do not tell us if the inputs can work up to that range as well. Often a +/- 5 V supply will result in a usable input voltage range of perhaps +/- 4 V. What is relevant is the Input Voltage Range which (according to table 6.5 in the TI datasheet: ti.com/lit/ds/symlink/lm741.pdf ) is typically +/- 13 V when a +/- 15 V supply is used. – Bimpelrekkie Nov 14 '18 at 9:13

If you mean with input voltage the supply voltage, yes. an LM741 is specified for +-22V (or +-18V)Supply voltage.

If you mean the input voltage on the input pins, also yes. If it is supplied with at least +-5V.

Have a look at the absolute maximum ratings table in the datasheet on page 4.

• Ahem, you're referring to the maximum ratings, these are the voltages that do not damage the opamp. These numbers do not say anything about the opamp actually working. Instead of maximum ratings, use operating conditions. – Bimpelrekkie Nov 14 '18 at 7:31