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Axelite Confidential Materials, do not copy or distribute without written consent.

Rev.1.6 Sep.24, 2019

AX2005/A

Inductor Selection

For most designs, the different frequency can be reducing the inductor value; The

AX2005/A is suggested 33uH.

Where is inductor Ripple Current. Large value inductors lower ripple current and small

value inductors result in high ripple currents. Choose inductor ripple current approximately

20% of the maximum load current 2A, ΔIL=0.4A. The DC current rating of the inductor

should be at least equal to the maximum load current plus half the ripple current to prevent

core saturation (2A+0.2A).

Input Capacitor Selection

This capacitor should be located close to the IC using short leads and the voltage

rating should be approximately 1.5 times the maximum input voltage. The RMS current

rating requirement for the input capacitor of a buck regulator is approximately 1⁄2 the DC

load current. A low ESR input capacitor sized for maximum RMS current must be used. A

220µF low ESR capacitor for most applications is sufficient.

Over Voltage Protection

The OVP voltage is set by outside resistance (R1 and R4). The external resistor sets

the OVP voltage according to the following equation:

)

1

R

4

R

1

(

V

)

OVP

(

V

OVP

OUT

+

×

=

If VOVP >0.85V, The OVP is happened that to disable the driver until VOVP <0.85V.

Output Capacitor Selection

For lower output voltage ripple and more stable LED current, higher value output

capacitor and low ESR is recommended. A 470uF electrolytic capacitor works for most of

the applications.