6

Atmel LED Driver-MSL3082

PIN #

NAME

DESCRIPTION

1

SCL

I²C serial clock Input

SCL is the I²C serial interface clock input.

2

SDA

I²C serial data I/O

SDA is the I²C serial interface data I/O.

3, 44

AD1,

AD0

I²C slave ID selection inputs

AD0 and AD1 select the device I²C slave address.

4

FLTB

Fault output (open drain, active low)

FLTB sinks current to GND when the MSL3082 detects a fault.

FLTB remains low until the fault registers have been read or EN is toggled low.

5

FBI

Efficiency Optimizer input

Connect FBI to FBO of the next device when chaining the Efficiency Optimizers.

If unused connect FBI to GND close to the device.

6

FBO

Efficiency Optimizer output

Connect FBO through a Schottky diode to the string power supply’s feedback node (Figure 4),

or to FBI of the previous device (Figure 5).

If unused leave FBO unconnected.

7, 43

GND

Power ground

Connect GND to system ground, to CGND and to EP with short, wide traces.

8, 11, 14, 17,

20, 23, 26, 29

S0 - S7

String 0 thru 7 source sense inputs

Connect S

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

9, 12, 15, 18,

21, 24, 27, 30

G0 - G7 String 0 thru 7 external MOSFET gate drive outputs

Connect G

10, 13, 16, 19,

22, 25, 28, 31

D0 - D7 String 0 thru 7 external MOSFET drain sense inputs

Connect D

32

VIN

Supply voltage input

Connect a 12V ±10% supply to VIN. Bypass VIN to GND with a 1µF ceramic capacitor placed close to VIN.

33

VDD

Internal 2.5V regulator capacitor connection

Bypass VDD to GND with a 10µF ceramic capacitor placed close to the device.

34

EN

Enable input (active high)

Drive EN high to turn on the MSL3082, drive EN low to turn off the MSL3082.

For automatic start-up, connect EN to VIN through a 100kΩ resistor.

35, 39

NC

No connection

Make no connection to NC.

36, 37, 38

CGND

Connect to ground

Connect CGND to system ground, to GND and to EP using short, wide traces.

40

PHI

Phase synchronization input

Drive PHI with an external signal from 40Hz to 10kHz to synchronize the PWM dimming to the signal at PHI.

Connect PHI to GND if unused.

41

GSC

Gate shift clock input

Drive GSC with the gate shift clock of the video signal up to 5MHz. GSC sets the resolution of PWM dimming.

Connect GSC to GND if unused.

42

PWM

PWM input

Drive PWM with a pulse-width-modulated signal with a duty cycle of 0% to 100% and frequency of 20Hz

to 50kHz to control the brightness of all LED strings.

Exposed Pad

EP

Power ground

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

Pin Descriptions