Details

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BUY MM74HC138N https://www.utsource.net/itm/p/1431676.html
3 to 8 Line Decoder; Package: DIP; No of Pins: 16; Container: Rail

Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Supply Voltage	VCC	-	2.0	-	6.0	V
Input Low Voltage	VIL	IL = 1 mA	0.3	-	-	V
Input High Voltage	VIH	IH = -0.04 mA	-	-	VCC - 1.5	V
Output Low Voltage	VOL	IOL = 8 mA	0.25	-	-	V
Output High Voltage	VOH	IOH = -0.4 mA	-	-	VCC - 0.25	V
Propagation Delay Time	tpd	VCC = 4.5 V, VI = 2.0 V to 3.5 V	-	18	-	ns
Power Dissipation	PD	-	-	-	100	mW
Operating Temperature	TA	-	-40	-	85	°C
Storage Temperature	TSTG	-	-65	-	150	°C

Instructions for Using MM74HC138N

1. Power Supply:

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

2. Enable Inputs:

   • The MM74HC138N has three enable inputs (G1, G2A, G2B). For normal operation, G1 should be high, and both G2A and G2B should be low.

3. Address Inputs:

   • The address inputs (A, B, C) determine which of the eight outputs (Y0 to Y7) is active. The active output is low when the corresponding binary address is applied to A, B, and C.

4. Output States:

   • When any of the enable inputs are not in the correct state, all outputs are high.
   • Only one output is low at any given time, with the rest being high.

5. Propagation Delay:

   • The propagation delay time (t_pd) is the time it takes for a change in the input to affect the output. It is typically 18 ns at V_CC = 4.5V.

6. Temperature Considerations:

   • Ensure the operating temperature is within -40°C to 85°C and the storage temperature is within -65°C to 150°C.

7. Power Dissipation:

   • The maximum power dissipation is 100 mW. Ensure proper heat sinking if the device is expected to operate near this limit.

8. Handling:

   • Handle the device with care to avoid static damage. Use proper ESD protection measures.

9. Testing:

   • Before integrating the MM74HC138N into a circuit, test its functionality using a simple breadboard setup to ensure it meets the required specifications.

(For reference only)