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Atmel LED Driver-MSL3085

PIN

PIN

NAME

PIN DESCRIPTION

21

S12

Source sense input 12

Source sense input for external MOSFET 12. Connect S12 to the source of the external MOSFET, and to the current

sense resistor for LED string 12. The full-scale LED current is reached when 500mV is across the current sense resistor.

22

G12

Gate output 12

Gate drive output for external MOSFET 12. Connect G12 to the gate of the external MOSFET driving LED string 12.

23

D12

Drain sense input 12

Drain sense input for external MOSFET 12. Connect D12 through a 10MΩ resistor to the drain of the external MOSFET

driving LED string 12.

24

S14

Source sense input 14

Source sense input for external MOSFET 14. Connect S14 to the source of the external MOSFET, and to the current

sense resistor for LED string 14. The full-scale LED current is reached when 500mV is across the current sense resistor.

25

G14

Gate output 14

Gate drive output for external MOSFET 14. Connect G14 to the gate of the external MOSFET driving LED string 14.

26

D14

Drain Sense Input 14

Drain sense input for external MOSFET 14. Connect D14 through a 10MΩ resistor to the drain of the external MOSFET

driving LED string 14.

27

VCC

5V internal LDO regulator output

VCC powers the FBO outputs. Bypass VCC to GND with a 4.7µF ceramic capacitor placed close to VCC.

28

PHI

Phase synchronization input

Drive PHI with an external signal of typically 100Hz to 480Hz to synchronize the MSL3085 LED PWM timing.

29

GSC

Gate shift clock input

Drive GSC with the gate shift clock of the video signal.

30

PWM

PWM input

PWM allows external control of the brightness of all LED strings. Drive PWM with a pulse-width-modulated signal with a

duty cycle of 0% to 100% and a frequency up to 5kHz. When not configured as an input, PWM is high impedance.

31

EN

Enable input (active high)

Drive EN high to turn on the MSL3085, and drive EN low to turn off the MSL3085. For automatic start-up, connect EN to

VIN. When EN is low, the entire device, including the serial interface, is turned off. Driving EN high initiates a boot load

of the EEPROM data into the control registers, simulating a cold start-up.

32

VIN

Supply voltage input

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

33

VDD

2.5V internal LDO regulator output

VDD powers internal logic. Bypass VDD to GND with a 4.7µF ceramic capacitor placed close to VDD.

34

S0

LED string 0 external MOSFET source input

Source sense input for external MOSFET 0. Connect S0 to the source of the external MOSFET, and to the current sense

resistor for LED string 0. The full-scale LED current is reached when 500mV is across the current sense resistor.

35

G0

Gate output 0

Gate drive output for external MOSFET 0. Connect G0 to the gate of the external MOSFET driving LED string 0.

36

D0

Drain sense input 0

Drain sense input for external MOSFET 0. Connect D0 through a 10MΩ resistor to the drain of the external MOSFET

driving LED string 0.

37

S2

LED string 2 external MOSFET source input

Source sense input for external MOSFET 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.

38

G2

Gate output 2

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

39

D2

Drain sense input 2

Drain sense input for external MOSFET 2. Connect D2 through a 10MΩ resistor to the drain of the external MOSFET

driving LED string 2.

40

S4

LED string 4 external MOSFET source input

Source sense input for external MOSFET 4. Connect S4 to the source of the external MOSFET, and to the current sense

resistor for LED string 4. The full-scale LED current is reached when 500mV is across the current sense resistor.

EP

EP

Exposed pad, power ground

Connect EP to system ground and to GND using short, wide traces. EP provides thermal relief for the die.

Atmel LED Driver-MSL3085

8-string White and RGB LED Driver with Adaptive Power