LTC3783
PWM LED Driver and Boost,
Flyback and SEPIC Controller
FEATURES DESCRIPTION
TM
n
True Color PWM Delivers Constant Color with The LTC 3783 is a current mode LED driver and boost,
3000:1 Dimming Ratio flyback and SEPIC controller that drives both an N-channel
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Fully Integrated Load FET Driver for PWM Dimming power MOSFET and an N-channel load PWM switch. When
Control of High Power LEDs using an external load switch, the PWMIN input not only
n
100:1 Dimming from Analog Inputs drives PWMOUT, but also enables controller GATE switch-
n
Wide FB Voltage Range: 0V to 1.23V ing and error amplifier operation, allowing the controller
n
Constant Current or Constant Voltage Regulation to store load current information while PWMIN is low.
n
Low Shutdown Current: I = 20A This feature (patent pending) provides extremely fast,
Q
n
1% 1.23V Internal Voltage Reference true PWM load switching with no transient overvoltage
n
2% RUN Pin Threshold with 100mV Hysteresis or undervoltage issues; LED dimming ratios of 3000:1
n
Programmable Operating Frequency can be achieved digitally, avoiding the color shift normally
(20kHz to 1MHz) with One External Resistor associated with LED current dimming. The FBP pin allows
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Synchronizable to an External Clock Up to 1.3f analog dimming of load current, further increasing the
OSC
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Internal 7V Low Dropout Voltage Regulator effective dimming ratio by 100:1 over PWM alone.
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Programmable Output Overvoltage Protection
In applications where output load current must be returned
n
Programmable Soft-Start
to V , optional constant current/constant voltage regula-
IN
TM
n
Can be Used in a No R Mode for V < 36V
SENSE DS
tion controls either output (or input) current or output
n
16-Lead DFN and TSSOP Packages
voltage and provides a limit for the other. I provides a
LIM
10:1 analog dimming ratio.
APPLICATIONS
For low- to medium-power applications, No R mode
SENSE
n
High Voltage LED Arrays
can utilize the power MOSFETs on-resistance to eliminate
n
Telecom Power Supplies
the current-sense resistor, thereby maximizing efficiency.
n
42V Automotive Systems
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24V Industrial Controls The ICs operating frequency can be set with an external
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IP Phone Power Supplies resistor over a 20kHz to 1MHz range and can be synchro-
nized to an external clock using the SYNC pin.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
True Color PWM and No R are trademarks of Linear Technology Corporation.
SENSE The LTC3783 is available in the 16-lead DFN and TSSOP
All other trademarks are the property of their respective owners.
packages.
TYPICAL APPLICATION
350mA PWM LED Boost Application Typical Waveforms
V
IN
6V TO 16V
10F
(< TOTAL V OF LEDs)
F
V
2.2H PWMIN
2
1M
5V/DIV
ZETEX ZLLS1000
V
OUT
LTC3783
V
<25V OUT
0.2V/DIV
237k
RUN V
IN
AC COUPLED
LED*
PWMIN OV/FB
STRING
I PWMOUT
TH
I
L
SS I
2.5A/DIV
LIM
105k
C
V GATE M1 M2 OUT
REF
10F
0.1F FBP SENSE
I
FBN INTV LED
10F CC
4.7F 0.5A/DIV
FREQ GND
SYNC
10k 6k 0.05 12.4k 0.3
3783 TA01b
1s/DIV
GND
3783 TA01a
M1, M2: SILICONIX Si4470EY *LUMILEDS LHXL-BW02
3783fb
1LTC3783
(Note 1)
ABSOLUTE MAXIMUM RATINGS
V , SENSE, FBP, FBN Voltages ................. 0.3V to 42V Operating Temperature Range (Note 2)
IN
INTV Voltage ............................................ 0.3V to 9V LTC3783E ............................................. 40C to 85C
CC
INTV Output Current .......................................... 75mA LTC3783I............................................ 40C to 125C
CC
GATE Output Current ................................. 50mA (RMS) Junction Temperature (Note 3) ............ 40C to 125C
PWMOUT Output Current .......................... 25mA (RMS) Storage Temperature Range
V Ouput Current ................................................. 1mA DFN Package ..................................... 65C to 125C
REF
GATE, PWMOUT Voltages .......0.3V to (V + 0.3V) TSSOP Package ................................ 65C to 150C
INTVCC
I , I , SS Voltages ............................... 0.3V to 2.7V Lead Temperature (Soldering, 10sec)
TH LIM
RUN, SYNC, PWMIN Voltages..................... 0.3V to 7V TSSOP Package ............................................... 300C
FREQ, V , OV/FB Voltages ..................... 0.3V to 1.5V
REF
PIN CONFIGURATION
TOP VIEW
TOP VIEW
FBN 1 16 RUN FBN 1 16 RUN
FBP 2 15 I FBP 2 15 I
TH
TH
I 3 14 OV/FB I 3 14 OV/FB
LIM LIM
V 4 13 SS V 4 13 SS
REF REF
17 17
FREQ 5 12 SENSE FREQ 5 12 SENSE
SYNC 6 11 V SYNC 6 11 V
IN
IN
PWMIN 7 10 INTV PWMIN 7 10 INTV
CC
CC
PWMOUT 8 9 GATE
PWMOUT 8 9 GATE
FE PACKAGE
DHD PACKAGE
16-LEAD PLASTIC TSSOP
16-LEAD (5mm 4mm) PLASTIC DFN
T = 125C, = 38C/W
T = 125C, = 43C/W JMAX JA
JMAX JA
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3783EDHD#PBF LTC3783EDHD#TRPBF 3783 16-Lead (5mm 4mm) Plastic DFN 40C to 85C
LTC3783IDHD#PBF LTC3783IDHD#TRPBF 3783 16-Lead (5mm 4mm) Plastic DFN 40C to 125C
LTC3783EFE#PBF LTC3783EFE#TRPBF 3783EFE 16-Lead Plastic TSSOP 40C to 85C
LTC3783IFE#PBF LTC3783IFE#TRPBF 3783IFE 16-Lead Plastic TSSOP 40C to 125C
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3783EDHD LTC3783EDHD#TR 3783 16-Lead (5mm 4mm) Plastic DFN 40C to 85C
LTC3783IDHD LTC3783IDHD#TR 3783 16-Lead (5mm 4mm) Plastic DFN 40C to 125C
LTC3783EFE LTC3783EFE#TR 3783IFE 16-Lead Plastic TSSOP 40C to 85C
LTC3783IFE LTC3783IFE#TR 3783IFE 16-Lead Plastic TSSOP 40C to 125C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: