Details

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BUY L4981A https://www.utsource.net/itm/p/12603875.html

Parameter	Symbol	Min	Typ	Max	Unit	Description
Input Voltage	VIN	4.5	-	40	V	Operating input voltage range
Output Voltage	VOUT	1.23	-	-	V	Fixed output voltage
Quiescent Current	IQ	-	65	-	μA	Supply current under no-load conditions
Dropout Voltage	VDROPOUT	-	1.2	-	V	Voltage difference between VIN and VOUT for regulation
Load Regulation	ΔVOUT/ΔILOAD	-	0.5	-	mV/mA	Change in output voltage with load current
Line Regulation	ΔVOUT/ΔVIN	-	0.01	-	%/V	Change in output voltage with input voltage
Ripple Rejection	RR	-	70	-	dB	Attenuation of input ripple at the output
Operating Temperature	Toper	-40	-	125	°C	Range of ambient temperatures for operation
Storage Temperature	Tstg	-65	-	150	°C	Range of temperatures for storage
Thermal Shutdown	TSD	-	160	-	°C	Temperature at which the device shuts down to prevent damage

Instructions for Using L4981A:

1. Power Supply Connection:

   • Connect the input voltage (VIN) to the input pin.
   • Ensure the input voltage is within the specified range (4.5V to 40V).

2. Output Configuration:

   • The output voltage (VOUT) is fixed at 1.23V.
   • Use appropriate capacitors and resistors to stabilize the output and filter noise.

3. Quiescent Current:

   • The quiescent current (IQ) is typically 65 μA, which is relatively low, making it suitable for battery-powered applications.

4. Dropout Voltage:

   • The dropout voltage (VDROPOUT) is approximately 1.2V. Ensure that the input voltage is at least 1.2V higher than the desired output voltage to maintain regulation.

5. Load Regulation:

   • The load regulation is 0.5 mV/mA, indicating a small change in output voltage with changes in load current.

6. Line Regulation:

   • The line regulation is 0.01%/V, ensuring minimal changes in output voltage with variations in input voltage.

7. Ripple Rejection:

   • The ripple rejection is 70 dB, effectively reducing input ripple at the output.

8. Operating Temperature:

   • The device operates over a temperature range from -40°C to 125°C.

9. Storage Temperature:

   • Store the device in temperatures ranging from -65°C to 150°C.

10. Thermal Shutdown:

    • The device will automatically shut down if the temperature exceeds 160°C to prevent damage.

11. Capacitor Selection:

    • Use ceramic or tantalum capacitors for input and output filtering. Typical values are 10 μF for input and 10 μF for output.

12. PCB Layout:

    • Place the input and output capacitors as close as possible to the respective pins to minimize parasitic inductance and improve stability.

13. Heat Dissipation:

    • If operating at high power levels, ensure adequate heat dissipation by using a heatsink or thermal pad.

By following these instructions, you can ensure optimal performance and reliability of the L4981A linear regulator in your application.

(For reference only)