Details

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BUY LM3103MHX https://www.utsource.net/itm/p/12606610.html

Below is the parameter table and instructions for the LM3103MHX:

LM3103MHX Parameter Table

Parameter	Symbol	Min	Typ	Max	Unit	Conditions
Input Voltage Range	VIN	4.5	-	60	V
Output Voltage Range	VOUT	0.8	-	55	V
Output Current	IOUT	-	2.0	3.0	A
Switching Frequency	fSW	100	500	1000	kHz
Quiescent Current	IQ	-	1.7	-	mA	VIN = 12V, No Load
Shutdown Current	ISD	-	0.1	-	渭A	VIN = 12V, Shutdown Mode
Enable Input High Voltage	VEN(HIGH)	1.2	-	1.4	V
Enable Input Low Voltage	VEN(LOW)	0.4	-	0.8	V
Soft-Start Time	tSS	-	4.0	-	ms
Overcurrent Protection	IFAULT	-	3.2	-	A
Thermal Shutdown Temperature	TSD	-	160	-	掳C

Instructions for LM3103MHX

1. Input Voltage (VIN):

   • Ensure the input voltage is within the range of 4.5V to 60V.
   • Use appropriate input filtering and transient protection to avoid damage.

2. Output Voltage (VOUT):

   • Set the output voltage using external resistors R1 and R2 in the feedback loop.
   • The formula for output voltage is: ( V_ = 1.23 left(1 + fracright) ).

3. Output Current (IOUT):

   • The maximum continuous output current is 3.0A. Ensure the inductor and other components can handle this current.
   • Use a suitable inductor with low DC resistance (DCR) to minimize power loss.

4. Switching Frequency (fSW):

   • Set the switching frequency by selecting an appropriate value for the external resistor RT.
   • The formula for switching frequency is: ( f_ = frac{1.1 times 10^6} ), where RT is in ohms.

5. Quiescent Current (IQ):

   • The quiescent current is typically 1.7mA at 12V input. This should be considered in power budget calculations.

6. Shutdown Current (ISD):

   • When the enable pin (EN) is pulled low, the shutdown current is typically 0.1渭A.

7. Enable Pin (EN):

   • The enable pin can be used to turn the device on or off.
   • Apply a voltage greater than 1.2V to enable the device.
   • Apply a voltage less than 0.8V to disable the device.

8. Soft-Start Time (tSS):

   • The soft-start time is typically 4.0ms, which helps to reduce inrush current during startup.

9. Overcurrent Protection (IFault):

   • The device has built-in overcurrent protection that limits the output current to approximately 3.2A.
   • If the overcurrent condition persists, the device will enter a fault mode and shut down.

10. Thermal Shutdown (TSD):

    • The device will shut down if the junction temperature exceeds 160掳C.
    • Ensure proper heat sinking and airflow to prevent thermal shutdown.

11. Layout Considerations:

    • Place the input and output capacitors as close as possible to the IC to minimize noise and improve stability.
    • Use wide traces for high-current paths to reduce resistance and heat generation.

12. Component Selection:

    • Choose an inductor with a saturation current higher than the maximum output current.
    • Use low ESR (Equivalent Series Resistance) capacitors for both input and output to ensure stable operation.

By following these parameters and instructions, you can effectively design and implement a power supply using the LM3103MHX.

(For reference only)