LDS9003 / 9001
?009 IXYS Corp.
1
Doc. No. 9003/9001DS, Rev. N1.0
Characteristics subject to change without notice
High Power LED Temperature and PWM Controller
with LED-Sense
TM
In-Situ LED T
J
Sensing
FEATURES
?SPAN class="pst LDS9003-002-T2_2318383_8"> High temperature LEDcurrent de-rating and
thermal control using the LED-Sense
TM
algorithm thatdirectly monitors LED T
junction
?SPAN class="pst LDS9003-002-T2_2318383_8">  No external thermal sensor is required
?SPAN class="pst LDS9003-002-T2_2318383_8">  Up to three temperature sensing and control
channels on LDS9003 supports multi-point
thermal monitoring or multi-color LED
applications; LDS9001 is a single channel
?SPAN class="pst LDS9003-002-T2_2318383_8">  Programmable Temp vs. PWM Duty Cycle
profiles (3 for LDS9003; 1 for LDS9001)
?SPAN class="pst LDS9003-002-T2_2318383_8">  Integrated PWM for dimming control of high
brightness (HB)  LED  Drivers in  logarithmic
duty cycle steps from 0% to 100% (~ 0.17 dB /
step)
?SPAN class="pst LDS9003-002-T2_2318383_8">  PWM Dimming Control range of 256:1
?SPAN class="pst LDS9003-002-T2_2318383_8">  I
2
C compatible serial programming interface
?SPAN class="pst LDS9003-002-T2_2318383_8">  Interfaces  to  available  high  side  HB  LED
drivers and low cost microcontrollers
?SPAN class="pst LDS9003-002-T2_2318383_8">  LDS9003 is available in a small footprint
3 mm x 3 mm
2
16-pin TQFN
?SPAN class="pst LDS9003-002-T2_2318383_8">  LDS9001 is in a 3 x 2 mm
2
8-pin DFN
APPLICATIONS
?SPAN class="pst LDS9003-002-T2_2318383_8">  HB LED General Illumination Lighting
?SPAN class="pst LDS9003-002-T2_2318383_8">  Automotive LED Lighting
?SPAN class="pst LDS9003-002-T2_2318383_8">  Architectural LED Lighting
DESCRIPTION
The LDS9003 is a 3-channel and LDS9001 is a 1-
channel  LED  junction  temperature  monitor  and
control device intended for use in high power LED
solid state lighting applications. It connects directly to
a LED anode and the PWM input of available high
power HB drivers to real-time adjust LED current to
meet maximum  LED  temperature. A two  wire I
2
C
interface allows communication to a local low cost
microcontroller  or  other  remote  host  processor
device.
LDS9003 / 9001 can improve thermal management
of high power LED systems by controlling reliable
LED junction temperature levels to meet maximum
operating lifetimes. In addition, it can reduce cost by
allowing operation at optimal LED current/luminance
levels  minimizing the  number HB  LED  lamps  per
fixture required to meet illumination targets.
The LDS9003/9001 utilizes the LED-Sense"
sensing and control algorithm that directly measures
the LED junction and controls the temperature by
closed loop adjustment of the LED Driver current via
PWM duty cycle corrections.
The control loop real-time adjusts the LED current via
PWM correction codes in user programmed Look up
Tables (LUTs) assigned to each sensing channel.
The  user programs  desired  correction  profiles  for
every 5篊 increment from -35篊 to 120篊. A single
sensing channel and correction LUT is available in
the LDS900, whereas three correction profiles are
available   in   LDS9003   to   support   multi-point
temperature sensing or multi-color LED applications.
Integrated  PWM  generators  support dimming  and
LED  temperature  vs.  current  compensation.  The
PWM duty cycle is programmable via the I
2
C serial
interface from 0% to 100%. User-programmed 8-bit
codes are converted to 12-bit logarithmic steps of ~
0.17 dB per step. The PWM frequency is ~280 Hz to
minimize noise generation.
The EN logic input functions as a chip enable. A logic
HIGH applied at the EN pin allows the LDS9003 /
LDS9001  to  respond  to  I
2
C  communications.  An
optional  external  serial  interface  address  pin  is
available for use in multi-target applications.
The device operates from 2.5 to 5.5V.
The LDS9001 is available in an 8-lead 3 x 2 mm
2
DFN package. The LDS9003 is in a 16-lead 3 x 3
mm
2
TQFN package.