LM339 Voltage Comparator IC Pinout, Working Principle, Parameters
Hello friends! Welcome back to ElectroDuino. This blog is base on the LM339 Voltage Comparator IC. Here we will discuss the Introduction to LM339 Voltage Comparator IC, Pin Diagram, Working Principle of LM339 IC, Features, LM339 IC Equivalent IC, Different Packages, and its Applications.
Introduction
LM339 is one of the voltage comparator IC in the LMx39x IC series. It is a 14-pin IC, that consists of four independent voltage comparators. These comparators are specially designed to operate from a single power supply. Also, there will be a possibility of operation from dual supplies is possible, as long as the difference between the two supplies is 2 V to 36 V. This IC is manufactured by many Companies and available in different packages like SOIC-14, TSSOP-14, and PDIP-14.
Internal Structure of LM339 Voltage Comparator IC
The LM339 comparator IC consists of four inbuilt independent voltage comparators.
The positive inputs of the comparator 1, 2, 3, and 4 are connected to IC pin 3 and the negative inputs are connected to IC pin 12.
The Inverting input of comparator 1 is connected to IC pin 4 and the Non-Inverting input is connected to IC pin 5. The output of comparator 1 is connected to IC pin 2.
The Inverting input of comparator 2 is connected to IC pin 6 and the Non-Inverting input is connected to IC pin 7. The output of comparator 2 is connected to IC pin 1.
The Inverting input of the comparator 3 is connected to IC pin 8 and the Non-Inverting input is connected to IC pin 9. The output of comparator 3 is connected to IC pin 14.
The Inverting input of the comparator 4 is connected to IC pin 10 and the Non-Inverting input is connected to IC pin 11. The output of comparator 4 is connected to IC pin 13.
LM339 IC Pin Configuration / Pinout
| Pin No | Pin Name | Description |
| 1 | 2OUT | The output pin of the comparator 2 |
| 2 | 1OUT | The output pin of the comparator 2 |
| 3 | VCC | The positive Power supply of the comparator |
| 4 | 2IN- | Negative input pin of the comparator 2 |
| 5 | 2IN+ | Positive input pin of the comparator 2 |
| 6 | 1IN- | Negative input pin of the comparator 1 |
| 7 | 1IN+ | Positive input pin of the comparator 1 |
| 8 | 3IN- | Negative input pin of the comparator 3 |
| 9 | 3IN+ | Positive input pin of the comparator 3 |
| 10 | 4IN- | Negative input pin of the comparator 4 |
| 11 | 4IN+ | Positive input pin of the comparator 4 |
| 12 | GND | Ground |
| 13 | 4OUT | The output pin of the comparator 4 |
| 14 | 3OUT | The output pin of the comparator 3 |
Working Principle
The working of this voltage comparator IC is similar to other comparators ICs. Each comparator of this IC has three pins, these are inverting (-IN), non-inverting (+IN), and output. Now, we will use a single comparator from these four comparators to understand how it works.
Here we take two input voltages, these are voltages V1 and V2. Now we will compare these voltages by the comparator and an output is provided as Vo. The voltage V1 is connected to the non-inverting (+IN) input (pin 5) of the comparator and the voltage V2 is connected to the inverting (-IN) input (pin 4).
If the voltage at the inverting (-IN) input (V2) is greater than the non-inverting (+IN) input (V1), then the output will be logic zero.
V2>V1 the Vo = 0V or GND
If the voltage at the non-inverting (+IN) input (V1) is greater than the inverting (-IN) input (V2), then the output will be logic Vcc.
V1>V2 then Vo = VCC
Features of LM339 IC
| Parameter | Value |
| Single power supply Range | +3.0 V to +36 V |
| Dual power supplies Range | +18V and -18V |
| Low input offset voltage | 1mV |
| Low output saturation voltage | 130 mV at 4mA |
| Low supply current | 1.1 mA |
| Low Input Offset current | + or – 5 nA |
| Low input bias current | 25 nA |
| Compatible with logic forms. | TTL, MOS, and CMOS |
| Operating temperature | -25°C to 85°C |
| junction temperature | 150°C |
Packages of LM339 IC
The different packages of LM339 IC are available in the market. Here we will discuss few of them in below.
- The SOIC-14 package for LM339DG
- The SOIC-14 package for LM339DR2G
- The TSSOP-14 package for LM339DTBR2G
- The PDIP-14 package for LM339NG
LM339 Voltage Comparators IC Equivalent IC
LM311, LM324, LM397, LM139, LM239, LM2901, etc
Applications
- Square wave pulse generation and time delay generation
- Analog to digital conversion of signals
- Voltage Controlled Oscillators
- Peak detectors and in level detection applications
- Automotive
- Measuring instruments
- Transducer Amplifiers
