MAX485

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Instructions for Using MAX485:

1. Power Supply:

   • Ensure the supply voltage (VCC) is within the range of 3.0V to 5.5V.

2. Driver Operation:

   • The driver outputs high-level voltage (VOH) should be no less than VCC - 0.4V when the output current (IOL) is -4mA.
   • The driver outputs low-level voltage (VOL) should not exceed 0.4V when the output current (IOH) is 16mA.

3. Receiver Operation:

   • The receiver recognizes input voltages greater than 2.0V as high-level (VIH).
   • The receiver recognizes input voltages less than 0.8V as low-level (VIL).
   • The receiver outputs high-level voltage (VOHR) should be VCC - 0.4V at a load current (IL) of -4mA.
   • The receiver outputs low-level voltage (VOHL) should not exceed 0.4V at a load current (IH) of 4mA.

4. Driver Enable Logic Levels:

   • For enabling the driver, apply a voltage greater than 2.0V but less than VCC (DIH).
   • For disabling the driver, apply a voltage less than 0.8V (DIL).

5. Timing Considerations:

   • The propagation delay time (tPD) should not exceed 350ns under typical conditions (VCC = 5V, TA = 25°C).
   • The skew between driver and receiver (tSKEW) should not exceed 30ns under typical conditions (VCC = 5V, TA = 25°C).

6. General Usage Tips:

   • Connect the DE pin to VCC for continuous driver enable or use it with logic control for selective enabling.
   • Connect the RE pin to ground for continuous receiver enable or use it with logic control for selective enabling.
   • Use external termination resistors on the bus lines if necessary to match impedance and reduce reflections.