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555 timer Li'lBoard page.
Model number: LB3.01.
Description: The classic 555 timer chip. The board is set up so that the chip can be configured as an astable or monostable multivibrator, and it allows a wide range of timing components to be used.
Applications: Pulse or frequency generation over a wide supply range and over a wide time range. Pulse (monostable) mode can be triggered by edge or level.
Features:
•A wide size range for the timing capacitor can be accommodated, including axial-lead electrolytics;
•A diode has been added to extend the duty cycle of the astable mode beyond 50%;
•The on-board LED can be set up to light on either the high or low output polarity;
•The timing resistors, R1 and R2, can be (0805 size) surface mount and/or 1/8 W through-hole devices. One good way to use this capability is to put in a SMD part selected for the maximum resistance appropriate to the needs, then parallel in a high-value 1/8 W device to calibrate the circuit's timing;
•The 555's reset and control voltage pins are accessible and labelled.
Key components: CMOS 555
Support page: Click here
Restrictions: The LED's resistor is sized for the board's maximum 16 V
Images:
Click on image for full (PDF) schematic
Vin max: 16
Vin min: 2
SPI: N/A.
Tenth centers: YES