Datasheet

14
Atmel MSL2010 [DATASHEET]
42072A–AVR–05/2013
9. Typical Application Circuit
MSL2010 Boost Switcher and Linear Driver, Driving 10 White LEDs.
Figure 9-1. Typical application circuit
10. Detailed Description
The MSL2010 drives one LED string, and includes a Boost Regulator Controller to generate V
LED
, the string voltage, from
a low voltage input. An Efficiency Optimizer (EO) algorithm regulates V
LED
to the minimum required to keep the LEDs in
current regulation, minimizing power loss across the external string drive MOSFET. A PWM input accepts 1% to 100%
duty cycle signal of 60Hz to 10kHz. The LED PWM output dimming duty cycle and frequency equal the PWM input duty
cycle and frequency, with a 2µs minimum on time. LEDs are driven by a linear driver.
11. Fault Conditions
Over Temperature Protection shuts down the device when the die temperature is above 133

C. The device turns back on
when the die temperature falls below 118

C, as if EN is taken from low to high.
12. Applications Information
12.1 Turn-On Sequence
When EN is taken high, the MSL2010 waits for 6ms, then optimizes V
LED
, the LED string voltage, which typically takes
about 250ms, then begins to drive the LEDs based on the PWM input.
G
DRV
AVIN
12V
AGND
SDA SCL
CONFIGURATION INTERFACE
MSL2010
LED DRIVER
REXT
CS
PWM
PWM
+
-
1Ω
FBO
EN
10 WHITE
LEDS
PGND
47kΩ
4.7kΩ
D
PVIN
VCC
VDD
TOFF
S
(OPTIONAL)
46.4k
24.9k
10uF
10uF
1uF
330μH
1μF
0. 05Ω
LTST-C190EKT
FBEAO
100kΩ
FDD3860
30k
Ω
220pF
0.1μF
IRFR110
270μF