Details

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Parameter	Symbol	Conditions	Min	Typ	Max	Unit
Supply Voltage	VCC	Operating Range	3.0		5.5	V
Driver Output High-Level Voltage	VOH	IOL = -4 mA			VCC-0.4	V
Driver Output Low-Level Voltage	VOL	IOH = 16 mA	0		0.4	V
Receiver Input High-Level Voltage	VIH		2.0			V
Receiver Input Low-Level Voltage	VIL				0.8	V
Receiver Output High-Level Voltage	VOHR	IL = -4 mA	VCC-0.4		VCC-0.4	V
Receiver Output Low-Level Voltage	VOHL	IH = 4 mA	0		0.4	V
Driver Enable Input High-Level Voltage	DIH		2.0		VCC	V
Driver Enable Input Low-Level Voltage	DIL		0		0.8	V
Propagation Delay Time (max)	tPD	VCC = 5V, TA = 25掳C		350		ns
Driver to Receiver Skew (max)	tSKEW	VCC = 5V, TA = 25掳C		30		ns

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掳C).
   • The skew between driver and receiver (tSKEW) should not exceed 30ns under typical conditions (VCC = 5V, TA = 25掳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.

(For reference only)