The TLC555 Timer is an improved version of the venerable NE555 and is functionally interchangeable.
- TLC555I Timer
KEY FEATURES OF TLC555 TIMER:
- LinCMOS technology
- Monostable or Astable modes of operation.
- Adjustable duty cycle
- Up to 2.1MHz operation
- Sink up to 100mA
- DIP-8 Package
- 3-15V operation
- 3.3 and 5V compatible
The TLC555 is an upgrade to the NE555 Timer that is an old school IC that is still commonly used and belongs in every project box. It is probably the most versatile, yet easy to use IC ever created.
Compared to the NE555, the TLC555 offers the following main improvements:
- Maximum speed improves to 2.1MHz from 100kHz
- Wider voltage operation of 3-15V vs 4.5-15V so can be 3.3V logic compatible
- Lower power consumption of 250uA quiescent (typical) vs 3mA at 5V
- Higher input impedances allow smaller, higher precision timing capacitors to be used for improved timing precision
What’s the downside?
- The maximum sink current goes down to 100mA vs 200mA on the NE555 and maximum source current is 10mA vs 200mA on the NE555.
- Being a CMOS device, it is also a little more prone to damage from ESD.
Like the NE555, it can operate as a monostable, bistable or astable multivibrator. This allows it to be used in a variety of applications such as pulse generation, missing pulse detection, square wave generation, delay timers, LED flashers, tone generation and more.
Using the TLC555 generally entails hooking up a few resistors and perhaps a capacitor or potentiometer to set timing values. Timing can be adjusted from microseconds to hours.
The circuit shown here implements a simple metronome. It uses a potentiometer to adjust the timing of the ‘tock’ sound and can operate off a 9V battery. None of the values are overly critical.
|Maximum Ratings||Operating Voltage||3 – 15V|
|Supply Current (max)||500uA|
|Frequency Output (max)||2.1MHz|
|Source/Sink Current||10mA / 100mA|
|Package Type||Plastic, thru-hole|