Atmel LED Driver-MSL3085
8-string White and RGB LED Driver with Adaptive Power
Control, EEPROM, and I2C/SMBus Serial Interface
REGISTER NAME
AND ADDRESS
POWER-UP CONDITION
REGISTERS INITIALIZED FROM EEPROM
D7 D6
0x28
0x29
PHICNTR
Although disabled, internal PHI
Frequency fPGEN = 20MHz / (8 * (10416 + 1)) = 240Hz
10
00
0x2A PHIMUL PHI multiplier = 1 (register setting + 1)
00
0x2B
0x2C
PHIMAX
Although disabled, PHI maximum count = 4148
00
00
PWM operation enabled
0x2D
PWMCTRL0
Individual LED string drive pulse widths internally
determined
10
PWM input does not gate the output of the PWM engine
String on times allowed to extend beyond end of PWM
frame String on times allowed to extend into frame zero
Alternate timing not used
Global intensity (GINT) disabled
Although disabled, (GINT + 1) is provided to the
0x2E PWMCTRL1 PWM engine
String drive phasing enabled
00
Delayed string turn on beginning after PWM
frame allowed
Delayed turn on occurring in frame zero allowed
Alternate timing not selected by PWM input state
0x2F
GINT
Global intensity set to (127 + 1) / 255 = 50.2%
01
0x30 ALTGINT Alternate global intensity set to (95 + 1) / 255 = 37.6%
01
0x31
0x40
0x41
↓
0x5C
0x5D
ISTR
STR0SET
↓
STR14SET
Strings current set at 50% of RS setting
All strings phase delay = zero
All strings assigned to FBO1
01
00
01
00
01
0x60
0x61
PWM0
00
00
↓
↓
All strings have PWM value = 512 GSC cycles
0x7C
0x7D
PWM14
00
00
0x80
ALTSTR0SET
0x81
00
00
↓
↓
All strings alternate phase delay = zero
0x9C
ALTSTR14SET
0x9D
00
00
0xA0
0xA1
↓
0xBC
0xBD
ALTPWM0
↓
ALTPWM14
All strings set with alternate PWM value = 512 GSC
cycles
00
00
00
00
REGISTERS WITH FIXED INITIAL VALUES
0xC0 E2ADDR EEPROM 7-bit address = 0x00
00
0xC1 E2CTRLSTA EEPROM read/write disabled
00
REGISTER DATA
D5 D4 D3 D2 D1
1 100 0
1 010 0
0 000 0
1 101 0
0 100 0
0 110 0
0 001 1
1 111 1
0 111 1
1 111 1
0 000 0
0 000 0
↓
0 000 0
0 000 0
0 000 0
0 000 1
↓
0 000 0
0 000 1
0 000 0
0 000 0
↓
0 000 0
0 000 0
0 000 0
0 000 1
↓
0 000 0
0 000 1
0 000 0
0 000 0
D0 HEX
0 B0
0 28
0 00
0 34
0 10
1 99
1 07
1 7F
1 5F
1 7F
0 00
0 40
0 00
0 40
0 00
0 02
0 00
0 02
0 00
0 00
0 00
0 00
0 00
0 02
0 00
0 02
0 00
0 00
Atmel LED Driver-MSL3085
19