Details

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BUY LM555D https://www.utsource.net/itm/p/12617367.html

Parameter	Symbol	Min	Typ	Max	Unit
Supply Voltage	Vcc	4.5	-	16	V
Output Current (Sink)	Ioh	-	200	-	渭A
Output Current (Source)	Iol	-	200	-	渭A
Trigger Input Voltage	Vtrig	-	1/3Vcc	-	V
Threshold Input Voltage	Vthres	-	2/3Vcc	-	V
Reset Input Voltage	Vreset	-	0.7	-	V
Control Voltage	Vctrl	-	-	-	V
Maximum Operating Temp.	Tmax	-	85	-	掳C
Minimum Operating Temp.	Tmin	-	-40	-	掳C

Instructions for LM555D

1. Power Supply Connection:

   • Connect the supply voltage (Vcc) between pin 8 and ground (pin 1). Ensure Vcc is within the specified range of 4.5V to 16V.

2. Trigger Input (Pin 2):

   • The trigger input is active low. It triggers the timer when the voltage drops below 1/3 of Vcc.

3. Threshold Input (Pin 6):

   • This pin resets the timer when the voltage exceeds 2/3 of Vcc. For astable operation, connect this pin to the discharge pin (pin 7).

4. Control Voltage (Pin 5):

   • Provides a means to adjust the threshold and trigger levels. Typically bypassed to ground with a capacitor to avoid noise interference.

5. Discharge Pin (Pin 7):

   • Open collector output used to discharge an external capacitor. Connect it to the timing capacitor in astable mode.

6. Output (Pin 3):

   • Drives the load or next stage. Can source or sink up to 200mA.

7. Reset Input (Pin 4):

   • Active low reset. If not used, connect to Vcc to prevent false triggering.

8. Ground (Pin 1):

   • Connect all grounds here.

9. Operating Temperature:

   • Ensure the device operates within the temperature range of -40掳C to 85掳C.

10. Capacitor Selection:

    • Choose capacitors that can handle the required voltage and provide stable operation over temperature.

11. PCB Layout:

    • Keep the layout compact and minimize lead lengths to reduce noise pickup. Use bypass capacitors near the power pins for stability.

(For reference only)