What is SE555?
This is Precision Timer. It is a popular integrated circuit (IC) timer that is widely used in electronic circuits. It is also known as NE555, LM555, or simply 555 timer. The IC is a versatile timer that can be used to generate precise and stable time delays, oscillations, and pulse-width modulation signals.
Part Number: SE555
Function: Precision Timer
Package: PDIP, SOP, TSSOP, SOIC 8 Pin
Manufacturer: Texas Instruments
Pinouts:
Description:
These devices are precision timing circuits capable of producing accurate time delays or oscillation. In the time-delay or monostable mode of operation, the timed interval is controlled by a single external resistor and capacitor network. In the astable mode of operation, the frequency and duty cycle can be controlled independently with two external resistors and a single external capacitor.
The threshold and trigger levels normally are two-thirds and one-third, respectively, of Vcc. These levels can be altered by use of the control-voltage terminal. When the trigger input falls below the trigger level, the flip-flop is set, and the output goes high. If the trigger input is above the trigger level and the threshold input is above the threshold level, the flip-flop is reset and the output is low.
The reset (RESET) input can override all other inputs and can be used to initiate a new timing cycle. When RESET goes low, the flip-flop is reset, and the output goes low. When the output is low, a low-impedance path is provided between discharge (DISCH) and ground.
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. With a 5-V supply, output levels are compatible with TTL inputs.
Block Diagram
Features
1. Timing From Microseconds to Hours
2. Astable or Monostable Operation
3. Adjustable Duty Cycle
4. TTL-Compatible Output Can Sink or Source up to 200 mA
It has a number of useful features, including a wide operating voltage range (typically 4.5V to 18V), low power consumption, and high output current capability. It can be used in a variety of modes, as mentioned earlier, and can generate a range of output signals, including square waves, pulses, and ramps.
Advantages
The SE555 timer is a simple and versatile IC that is widely available and inexpensive. Its ease of use, low cost, and wide range of applications make it a popular choice for both hobbyists and professionals. Additionally, the timer is capable of driving a wide range of loads, including LEDs, motors, and relays, making it useful in a variety of circuits.
Disadvantages
While the timer has many advantages, it also has a few drawbacks. For example, it is not suitable for high-frequency applications due to its limited frequency range (typically up to a few hundred kilohertz). Additionally, the output of the timer can be affected by variations in temperature and supply voltage, which can lead to inaccuracies in timing.
Applications
1. Fingerprint Biometrics
2. Iris Biometrics
3. RFID Reader
SE555 Datasheet PDF Download
Other data sheets are available within the file: NA555, NE555, SA555, NA555D, NA555DG4