Do You Know About the NE555P Timer?
13 November 2023
Ⅱ. What are the features of NE555P timer?
Ⅲ. Symbol, footprint and pin configuration of NE555P timer
Ⅳ. What are the applications of NE555P timer?
Ⅴ. Technical parameters of NE555P timer
Ⅵ. Working principle and circuit diagram of NE555P timer
Ⅶ. What is the difference between NE555P and NE555?
Ⅷ. What is the difference between NE555P and NE555N?
Ⅸ. What are the advantages and disadvantages of NE555P timer?
In this article, you'll be introduced to the NE555P integrated circuit chip, which finds applications across various fields. After knowing about its features and applications, we will have a deep understanding of this chip and better apply it to actual projects.
NE555P is an integrated circuit chip commonly used in electronic equipment such as timers, pulse generators, and oscillators. In delay or monostable operating modes, the timing intervals are precisely controlled by a single external resistor and capacitor network. In astable operating mode, we can use two external resistors and an external capacitor to independently control frequency and duty cycle.
Its circuit contains twenty four transistors, two diodes and seventeen resistors, consisting of six parts including threshold comparator, trigger comparator, RS flip-flop, reset input, discharge and output. It is characterized by its eight-pin configuration and employs through-hole mounting for easy integration into electronic circuits. Operating within a frequency range of up to 0.5MHz, the NE555P demonstrates efficiency in timekeeping, pulse-width modulation, and oscillator circuits. Its adaptability is further underscored by a supply voltage range spanning from 4.5V to 16V, providing flexibility for different power requirements in diverse electronic systems.
Replacements and equivalents:
• NE555N
• SA555P
• It can work in oscillatory mode or monostable mode.
• It has high timing accuracy and good temperature stability.
• Its output terminal has a large supply current and can directly drive a variety of automatically controlled loads.
• It has a wide operating power supply voltage range and can be used with logic circuits such as TTL and CMOS. In other words, its output level and input trigger level can be combined with the high and low states of these logic series.
• A specific oscillation delay function can be achieved using just basic resistors and capacitors. The range of this delay is extensive, spanning from a few microseconds to several hours.
The symbol, footprint and pin configuration of NE555P are shown in the figure below.
It has a total of eight pins, their names and functions are as follows:
Pin 1 (Ground): This is the ground wire that is usually connected to the circuit common ground.
Pin 2 (Trigger Point): This pin is the time period that triggers the NE555 to start it. The upper edge voltage of the trigger signal must be greater than 2/3 VCC, and the lower edge must be lower than 1/3 VCC.
Pin 3 (Output): When the time period begins, the output pin is moved to a high potential of 1.7 volts less than the supply voltage during the voltage period of the 555. At the end of the cycle, the output will return to a low level of approximately 0 volts. At high potential, its maximum output current is about 200mA.
Pin 4 (Reset): A low logic level sent to this pin will reset the timer and return the output to a low level. It is usually connected to the positive power supply or left unused.
Pin 5 (Control): This pin allows the trigger and gate voltages to be changed by external voltages. This input can be used to change or adjust the output frequency when the timer is operating in stable or oscillatory operation.
Pin 6 (Reset Lock): Resets the lock and takes the output low. This action is initiated when the voltage on this pin moves from below 1/3VCC to above 2/3VCC.
Pin 7 (Discharge): This pin has the same current output capability as the main output pin. When the output is on, it is low and has low impedance to ground. When the output is off, it is high and has high impedance to ground.
Pin 8 (Vcc): This is the positive supply voltage terminal of the 555 timer IC. The supply voltage range is 4.5V to 16V.
• Alarm: It can be used to make an alarm, for example, by driving a speaker to sound an alarm, or by controlling a relay or other devices to achieve an alarm function.
• Pulse width modulation (PWM): NE555P can be used to generate PWM signals for controlling motors, LED brightness adjustment, etc.
• Pulse generator: NE555P can be used to generate pulse signals. By adjusting the resistor and capacitor values, it can achieve different pulse widths and frequencies.
• Voltage controlled oscillator: It can be used to construct a voltage controlled oscillator whose frequency can be adjusted by an external voltage.
• Oscillator: It can also be used as an oscillator to generate signals such as sine waves and square waves with a certain frequency and amplitude, which are used as signal sources or clock sources in circuits.
• Flash controller: It is commonly used in photography and flash control circuits to achieve precise flash timing.
• Timer: It serves as a timer in various applications such as timers, delay systems, and clock circuits, enabling the measurement of time intervals.
It generates periodic pulses through an RC circuit composed of capacitors and resistors, thereby realizing functions such as timers, pulse generators, and oscillators. Next, we take a simple LED flashing circuit as an example to introduce the working principle diagram and circuit diagram of NE555P in detail.
This circuit uses the NE555P chip as a timer to achieve the LED flashing effect by adjusting the resistance and capacitance. Capacitor C1 and resistor R1 form an RC circuit, which is used to control the frequency and duty cycle of the pulse. R2 and LED are the output ports. The NE555P chip controls the output voltage to control the LED on and off.
The working principle of the NE555P chip is as follows:
1. Start timing: When the circuit is started, capacitor C1 begins to charge, and its voltage gradually increases.
2. Reaching the comparison threshold: When the voltage of capacitor C1 reaches the comparison threshold (Vcc*2/3), the NE555P chip will output a high level and turn off the discharge tube at the same time, causing the capacitor to stop charging.
3. Reaching the reset threshold: When the voltage of capacitor C1 drops to the reset threshold (Vcc*1/3), the NE555P chip will output a low level and open the discharge tube at the same time, causing the capacitor to start discharging.
4. Cycle timing: When the voltage of capacitor C1 drops below the comparison threshold, the NE555P chip will restart the charging cycle, thus forming a periodic pulse.
NE555P and NE555 are actually the same chip. The difference lies in the package. NE555 usually adopts SOP-8 patch package, which is suitable for automated production of PCB. The NE555P uses a DIP-8 plug-in package, which is suitable for use on breadboards. For electronics enthusiasts, it is recommended to choose NE555P or NE555N when conducting electronic production or experiments. Both of these are plug-in packages, which are more convenient to weld. For product designers, it is recommended to use the SOP-8 packaged NE555, which can reduce the area of the PCB board.
NE555N and NE555P are different specific models of the NE555 series. They differ in package form and parameter range. Generally speaking, NE555N adopts DIP package form, so it is suitable for experimental design on breadboard. The NE555P is a dual in-line package. It comes with some extra pins that help secure the chip better to the motherboard.
In addition, the operating voltage range of NE555N and NE555P is also different. The operating voltage range of NE555N is 4.5V to 16V, while the operating voltage range of NE555P is wider, covering 3V to 18V. Therefore, we need to consider the chip application to select the appropriate model and package.
1. Advantages of NE555P
(1) High reliability: It boasts a straightforward internal configuration and features a broad operating voltage range, ensuring exceptional reliability and an extended lifespan.
(2) High accuracy: NE555P has high timing accuracy and stable performance, which can meet the needs of most circuit designs.
(3) Stable output: It can provide stable and reliable square wave, rectangular wave and triangle wave signal output, and is suitable for various circuit designs.
(4) Wide operating voltage range: Its operating voltage range is 4.5 V to 16V, allowing it to work normally under different power supply conditions.
2. Disadvantages of NE555P
(1) Large power consumption: Although the NE555P has excellent performance, its power consumption is relatively large, which may pose limitations to some applications that require higher power consumption.
(2) Does not support digital signal input: It only supports analog signal input. For some applications that require digital signal input, additional conversion circuits may be required.
(3) The output frequency is susceptible to temperature and power supply voltage: Although the output frequency of NE555P is relatively stable, it is still affected by changes in temperature and power supply voltage, which may limit some high-precision applications.
Frequently Asked Questions
1. What is the maximum voltage for NE555P?
The output circuit is capable of sinking or sourcing current up to 200 mA. Operation is specified for supplies of 5 V to 15 V.
2. What is the replacement and equivalent of NE555P?
You can replace the NE555P with the NE555N, NE555PSLE or SA555P.
3. What is the function of NE555P?
These devices are precision timing circuits capable of producing accurate time delays or oscillation. In the time-delay or mono-stable mode of operation, the timed interval is controlled by a single external resistor and capacitor network.
4. What does NE555P do?
The chips 555 are a family of integrated circuits that are used for signal generation and as timers. In the time-delay or monostable mode operation, the time interval can be controlled with a resistor and external capacitor.
5. What is the difference between NE555N and NE555P?
NE555N generally operates within a voltage range of 4.5V to 16V. This range makes it suitable for a wide range of low to moderate voltage applications. NE555P has a slightly broader operating voltage range, typically from 4.5V to 18V.
