LM741CN features, parameters and pin function introduction
Published time: 2020-05-15 18:31:50
LM741CN is a general-purpose operational amplifier with very wide application. Due to the use of active loads, so long as two-stage amplification can achieve a very high voltage gain and a wide range of common-mode and differential-mode input voltage. This circuit uses internal compensation, the circuit is relatively simple and not easy to self-excitation, the working point is stable, easy to use, and the design of a perfect protection circuit is not easy to damage. LM741CN can be used in various digital instruments and industrial automatic control equipment.
(1) No local frequency compensation is required
(2) The input has overvoltage protection
(3) The output has overload protection
(4) No blocking and oscillation phenomenon
Absolute maximum rating: (TA = 25 ℃)
Power supply voltage: ± 22V
Power consumption: 500mW
Differential mode input voltage: ± 30V
Input voltage: ± 15V
Operating temperature range: -55 ℃ ~ + 125 ℃
Storage temperature range: -65 ℃ ~ + 150 ℃
Welding temperature: 300 ℃
Basic wiring diagram
Circuit schematic diagram:
3. Pin function
LM741CN is an 8-pin DIP chip, which means it has 8 pins, and they all have different functions.
LM741CN pin function description
pin name description
1.5 OFFSET is empty
Pins are used to eliminate offset voltage and balance input voltage
2 INPUT- Inverted signal input
Non-inverting signal input
4 V- Ground or negative supply voltage
6 OUTPUT Operational amplifier output
7 V+ Positive supply voltage
8 NC not connected
4. Working principle
When the voltage of the non-inverting input (+) is higher than the voltage of the inverting input (-), the output of the comparator is high. If the voltage at the inverting input (-) is higher than the non-inverting terminal (+), the output is low. The output of an op amp is the product of gain and input voltage.
5. How to use
An LM741 operational amplifier is a DC-coupled high-gain electronic voltage amplifier. There is only one operational amplifier inside. The operational amplifier IC is used as a comparator to compare two signals, namely, inverted and non-inverted signals. The main function of this IC is to perform mathematical operations in various circuits. Operational amplifiers have great gains and are commonly used as voltage amplifiers. LM741CN can use single power supply or dual power supply.
Operational amplifiers can be used in two ways:
(1) Inverting operational amplifier
When the input source is connected to the inverting terminal PIN 2 and feedback through the output PIN 6, the operational amplifier is in the inverting state. Just as PIN 2 has + ve polarity, we will get the polarity of PIN 6 output.
GAIN = Rf / R1
(2) Non-inverting operational amplifier
When the input source is connected to the non-inverting terminal PIN 3 and PIN 2 is fed back through the output PIN 6, the operational amplifier is in a non-inverting state. Just as PIN 3 has a + ve polarity, we will get the + ve polarity output by PIN 6.
GAIN = 1+ (Rf / R1)