Details

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BUY 74HC123 https://www.utsource.net/itm/p/12608479.html

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Supply Voltage	VCC	-	2.0	4.5	6.0	V
Input Low Voltage	VIL	VCC = 4.5V	0.8	-	-	V
Input High Voltage	VIH	VCC = 4.5V	-	-	3.5	V
Output Low Voltage	VOL	IL = 4mA	0.1	-	0.4	V
Output High Voltage	VOH	IH = -4mA	4.1	-	4.5	V
Propagation Delay Time (Low to High)	tPLH	VCC = 4.5V, TA = 25掳C	-	12	-	ns
Propagation Delay Time (High to Low)	tPHL	VCC = 4.5V, TA = 25掳C	-	12	-	ns
Power Consumption per Gate	Ptot	VCC = 4.5V, f = 1MHz	-	10	-	渭W

Instructions for Using the 74HC123 Dual Monostable Multivibrator

1. Power Supply:

   • Connect the V_CC pin to the positive supply voltage (2.0V to 6.0V).
   • Connect the GND pin to the ground.

2. Input Signals:

   • Apply trigger signals to the A (Trigger) pins. The input low voltage (V_IL) should be less than 0.8V when V_CC is 4.5V.
   • The input high voltage (V_IH) should be greater than 3.5V when V_CC is 4.5V.

3. Output Signals:

   • The output Q will go high when a valid trigger signal is applied to the A pin.
   • The output Q will return to low after the time period determined by the external RC circuit.

4. External RC Circuit:

   • Connect an external resistor (R) and capacitor (C) to the R and C pins respectively.
   • The time period (T) of the monostable pulse is given by: [ T = 0.45 times R times C quad text{(for one-shot mode)} ]
   • For retriggerable mode, the output can be extended by applying additional triggers before the initial pulse ends.

5. Reset Function:

   • The reset pin (RST) can be used to force the output Q to low immediately. Connect it to V_CC or GND as needed.

6. Operating Temperature:

   • Ensure the device operates within the specified temperature range (-40掳C to 85掳C).

7. Storage and Handling:

   • Store the device in a dry environment to prevent moisture damage.
   • Handle with care to avoid static discharge, which can damage the IC.

8. Testing and Troubleshooting:

   • Verify the power supply connections and ensure they are within the specified range.
   • Check the input signals and ensure they meet the required voltage levels.
   • Measure the output signals to confirm the correct operation of the monostable multivibrator.

(For reference only)