DA6251.002

27 October, 2017

11 (21)

VIN/(R1+R2) since VOUT follows VIN voltage when the device is in shutdown. To keep the shutdown current low

the external feedback resistance (R1+R2) path should be kept near 10M

 level. For good feedback regulation the

max R1 should not exceed 400k

.

When driving LEDs they are connected in series from VOUT to ILED which is the current sink pin. Additionally LED

current setting resistor RLED needs to be connected from RLED pin to GND. See figures 4-6. The table 4 shows

example RLED resistor values and corresponding LED current levels. Additionally PWM signal can be applied to

the CTRL pin for LED dimming to reduce average LED current from level defined with the RLED resistor.

Table 4. LED current setting resistor examples

RLED

[

Ω]

ILED

[mA]

40.2

5.0

20

10.0

13.3

15.0

Note: ILED=VRLED/RLED, VRLED=0.2V typ