6

Atmel LED Drivers-MSL2041/2042

PIN

NAME

DESCRIPTION

MSL2041 MSL2042

19

19

G2

Gate output 2

Gate drive output for external MOSFET 2. Connect G2 to the gate of the external MOSFET

driving LED string 2. If unused, connect G2 to ground.

20

20

S2

Source sense input for string 2

Connect S2 to the source of the external MOSFET, and to the current sense resistor for

LED string 2. The full scale LED current is reached when 500mV is across the current sense

resistor. If unused, connect S2 to VDD.

21

21

S3

Source sense input for string 3

Connect S3 to the source of the external MOSFET, and to the current sense resistor for

LED string 3. The full scale LED current is reached when 500mV is across the current sense

resistor. If unused, connect S3 to VDD.

22

22

G3

Gate output 3

Gate drive output for external MOSFET 3. Connect G3 to the gate of the external MOSFET

driving LED string 3. If unused, connect G3 to ground.

23

23

D3

Drain sense input 3

Drain Sense Input for External MOSFET 3. Connect D3 through a resistor to the drain of the

external MOSFET driving LED string 3. If unused, connect D3 to ground.

25

25

VDD

2.5V internal LDO regulator output

VDD powers internal logic. Bypass VDD to GND with a 2.2µF ceramic capacitor placed close

to VDD.

26

26

CVDD

Connect to VDD

Connect CVDD to VDD.

27

27

VCC

5V internal LDO regulator output

VCC powers internal logic. Bypass VCC to GND with a 2.2µF ceramic capacitor placed close

to VCC.

28

28

VIN

Supply voltage input

Connect a 12V ±10% supply to VIN. Bypass VIN to GND with a 1.0µF ceramic capacitor.

29

29

GND

Power ground

Connect GND to system ground.

30

30

FBI2

Efficiency Optimizer feedback input 2

Connect FBI2 to FBO2 of the previous device when using the devices in a chain

configuration. If unused, connect FBI2 to ground.

31

31

FBO2

Efficiency Optimizer feedback output 2

Connect FBO2 to the feedback node of the second external string power supply through a

diode, or to FBI2 of the next device when operating the devices in a chain configuration. If

unused, leave FBO2 unconnected.

32

32

FBI1

Efficiency Optimizer feedback input 1

Connect FBI1 to FBO1 of the previous device when using the devices in a chain

configuration. If unused, connect FBI1 to ground.

-

3, 4, 5

CGND

Connect to ground

Connect all CGND pins to GND as close to the MSL2042 as possible.