Details

---

BUY 74LS253 https://www.utsource.net/itm/p/12554035.html

Parameter	Symbol	Min	Typical	Max	Unit	Notes
Supply Voltage	VCC	4.75	5.0	5.25	V	Operating range for TTL logic
Input High Voltage	VIH	2.0	-	5.0	V	Minimum voltage recognized as a high level
Input Low Voltage	VIL	0.0	-	0.8	V	Maximum voltage recognized as a low level
Output High Voltage	VOH	2.7	-	5.0	V	Minimum output voltage when driving a low input
Output Low Voltage	VOL	0.0	-	0.5	V	Maximum output voltage when driving a high input
Input Leakage Current	IIL	-1.0	-	0.1	mA	Maximum current into an input pin
Output Drive Current (High)	IOH	-0.4	-	-	mA	Maximum current sourced by an output pin
Output Drive Current (Low)	IOL	-	-	8.0	mA	Maximum current sunk by an output pin
Propagation Delay Time	tpd	9	-	18	ns	Time delay from input change to output change
Power Dissipation	Ptot	-	-	100	mW	Maximum power dissipation per package

Instructions for Using the 74LS253

1. Power Supply:

   • Connect V_CC to +5V and GND to 0V.
   • Ensure the supply voltage is within the specified range to avoid damage.

2. Input Signals:

   • Apply logic levels (0V for low, 5V for high) to the input pins.
   • Ensure input voltages are within the specified limits to prevent incorrect operation or damage.

3. Output Signals:

   • The outputs can drive standard TTL loads.
   • Do not exceed the maximum output current ratings to avoid damaging the device.

4. Multiplexer Operation:

   • The 74LS253 is a dual 4-to-1 multiplexer.
   • Use the select lines (S0, S1) to choose which input (I0 to I3) is connected to the output (Y).
   • For each multiplexer section, the select lines determine the active input:
     • S0 = 0, S1 = 0: I0 → Y
     • S0 = 1, S1 = 0: I1 → Y
     • S0 = 0, S1 = 1: I2 → Y
     • S0 = 1, S1 = 1: I3 → Y

5. Enable Control:

   • The enable inputs (E1, E2) control whether the multiplexer is active.
   • Set E1 and E2 to low (0V) to enable the multiplexer.
   • Set E1 or E2 to high (5V) to disable the multiplexer, placing the outputs in a high-impedance state.

6. Propagation Delay:

   • Consider the propagation delay when designing circuits to ensure proper timing and synchronization.

7. Thermal Management:

   • Ensure adequate heat dissipation if operating at the maximum power dissipation limit.
   • Avoid exceeding the maximum power dissipation to prevent overheating and potential failure.

8. Storage and Handling:

   • Store the device in a dry, static-free environment.
   • Handle with care to avoid physical damage or electrostatic discharge (ESD).

By following these guidelines, you can effectively use the 74LS253 in your digital circuit designs.

(For reference only)