750 mV

R3

2

2

t

L2 =

1

K

1

u

1

K

1

u

L2

'i

LM3444

SNVS682C – NOVEMBER 2010 – REVISED MAY 2013

www.ti.com

(20)

Where:

(21)

Finally:

(22)

Refer to “Design Example” section of the datasheet to better understand the design process.

SETTING THE LED CURRENT

inductor current.

Figure 19. Inductor Current Waveform in CCM

an application running in continuous conduction mode (CCM) is defined as follows:

(23)

Or the LED current would then be,

(24)

This is important to calculate because this peak current multiplied by the sense resistor R3 will determine when

the internal comparator is tripped. The internal comparator turns the control MOSFET off once the peak sensed

voltage reaches 750 mV.

(25)

16

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