Linear Technology DC1744A Quick setup guide

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DEMO MANUAL DC1744A
Description
LT3799
Offline Isolated Flyback
LED Driver with PFC
Demonstration circuit 1744A is an off-line isolated flyback
converter featuring the LT
®
3799. The demo board is de-
signed to drive a single LED from an input voltage range
of 90V AC to 270V AC. It is also designed to comply with
IEC 61000-3-2 Class C harmonics standard andEN55015B
conducted EMI standard.
The LT3799 controls an isolated flyback converter in
boundary mode, suitable for LED applications requiring
4W to over 100W of LED power. Its novel current sensing
scheme delivers a well-regulated output current to the
secondary side without using an opto-coupler. Its unique
bleeder circuit makes the LED driver compatible with L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
perForMAnce sUMMArY
TRIAC dimmers without additional components. Open-
and shorted-LED protection ensures long-term reliability.
The LT3799 is availablein a lowprofile, thermally-enhanced
16-lead MSOP package.
The LT3799 data sheet gives a complete description of
the part, operation and application information. The data
sheet must be read in conjunction with this quick start
guide for demo circuit 1744A.
Design files for this circuit board are available at
http://www.linear.com/demo.
(TA= 25°C)
PARAMETER CONDITIONS VALUE (TYPICAL)
Input Range Line Frequency, 50Hz/60Hz 90V AC to 270V AC
Output Current IOUT VIN = 120V AC, VLED = 3.6V 1.07A
Maximum Output Voltage 5V
Minimum Output Voltage 3V
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DEMO MANUAL DC1744A
qUick stArt proceDUre
Figure 1. Proper Measurement Equipment Setup
IMPORTANT NOTE TO CUSTOMERS:
HIGH VOLTAGES ARE PRESENTED ON THE DEMO CIR-
CUIT, AND CAN LEAD TO LETHAL INJURIES TO HUMAN
BODY. ONLYQUALIFIEDPERSONNELSHOULDOPERATE
IT. IT IS STRONGLY RECOMMENDED TO USE SAFETY
GLASSES AND AN ISOLATION TRANSFORMER.
NOTE. IMPROPER COMPONENTS REPLACEMENT ON
THE DEMO CIRCUIT CAN CAUSE PERFORMANCE DE-
TERIORATIONS, CIRCUIT MALFUNCTION, PROPERTY
DAMAGE, AND EVEN LIFE-THREATHENING INJURIES.
CONTACT LINEAR TECHNOLOGY APPLICATIONS EN-
GINEERS FOR PROPER COMPONENT REPLACEMENT.
Demonstration circuit 1744A is easy to set up to evalu-
ate the performance of the LT3799. Refer to Figure 1 for
proper measurement equipment setup and follow the
procedure below:
1. Connect a 1A LED between LED+and LED–terminals.
2. With power off, connect the input power supply to Line
(L) Input and Neutral (N) Input.
3. Turn on the power at the input.
NOTE: Make sure that the input voltage does not exceed
the maximum input voltage (270V AC).
4. Check for the proper output current.
Once the proper output currents are established, adjust
the input voltage and/or the load and observe the output
current regulation, efficiency, power factor and other
parameters.
V
+
–
A
~
A
– +
~
AC
POWER SUPPLY
90V AC TO 270V AC
V
~
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DEMO MANUAL DC1744A
qUick stArt proceDUre
TRIAC ANGLE (DEG)
0
0
I
LED
(A)
0.2
0.4
0.6
0.8
1.2
30 60 90 120
DC1744 F02
150 180
1.0
Figure 2. LED Current vs TRIAC Angle (120V AC Application)
Figure 3. Power Factor vs Input Voltage
VIN (VAC – RMS)
90
POWER FACTOR
0.95
0.93
0.97
0.99
150 210 270
DC1744A F03
0.91
0.89
0.87
0.85 110 130 170 190 230 250
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DEMO MANUAL DC1744A
pArts list
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 B1 RECTIFIER, BRIDGE 600V 0.8A DIODES INC. HD06-T
2 1 C1 CAP, 33nF 20% 310V AC MKP VISHAY BFC233920333
3 1 C2 CAP, 1812 22nF 5% 630V C0G TDK C4532C0G2J223J
4 1 C3 CAP, 1210 10µF 20% 50V X7S TAIYO YUDEN UMK325C7106MM-T
5 1 C4 CAP, 68nF 10% 450V RADIAL RUBYCON 450MMK683K
6 1 C6 CAP, 0603 0.1µF 10% 16V X7R MURATA GRM188R71C104KA01D
7 1 C7 CAP, 0603 68nF 10% 50V X7R AVX 06035C682KAT2A
8 1 C8 CAP, 0805 4.7µF 10% 25V X5R TDK C2012X5R1E475K
9 1 C13 CAP, 0805 2.2nF 10% 250V U2J MURATA GRM21A7U2E222JW31D
10 1 C20 CAP, 2.2nF 10% 550VAC TYPE “Y1” VISHAY 440LD22-R
11 1 C21 CAP, 0603 4.7pF ±0.25pF 50V NP0 AVX 06035A4R7CAT2A
12 1 C22 CAP, 1500µF 20% 6.3V ELEC SANYO 6SEPC1500M+T
13 1 D1 DIODE, ULTRA FAST RECOVERY RECTIFIER CENTRAL SEMI CMMR1U-06 TR
14 2 D2, D8 DIODE, FAST SWITCHING DIODES/ZETEX BAV20W-7-F
15 1 D7 DIODE, SCHOTTKY BARRIER RECTIFIER CENTRAL SEMI CMSH2-40L TR13
16 1 D9 DIODE, ZENER 33V DIODES INC SMAZ33-13-F
17 3 L1, L2, L3 IND, 3.3mH, SMD COILCRAFT LPS6235-335ML
18 1 Q1 XSTR, MOSFET, N-CHANNEL 600V INFINEON SPU04N60C3
19 2 R1, R5 RES, 1206 100k 5% 1/4W VISHAY CRCW1206100KJNEA
20 1 R2 RES, 0805 200k 5% 1/8W VISHAY CRCW0805200KJNEA
21 2 R3, R18 RES, 0603 100k 1% 1/10W VISHAY CRCW0603100KFKEA
22 1 R4 RES, 0603 4.99k 1% 1/10W VISHAY CRCW06034K99FKEA
23 1 R8 RES, 1206 300mΩ 1% 1/4W VISHAY RCWE1206R300FKEA
24 1 R9 RES, 0603 20Ω 5% 1/10W VISHAY CRCW060320R0JNEA
25 1 R10 RES, 1210 100Ω 5% 1/4W VISHAY CRCW1210100R0JNEA
26 2 R11, R16 RES, 1206 499k 1% 1/4W VISHAY CRCW1206499KFKEA
27 1 R12 RES, 0603 3.48k 1% 1/10W VISHAY CRCW06033K48FKEA
28 2 R17, R24 RES, 0805 10k 5% 1/8W VISHAY CRCW080510K0JNEA
29 1 R19 RES, 0603 40.2k 1% 1/10W NIC NRC06F4022TRF
30 1 R20 RES, 0603 24.9k 1% 1/10W VISHAY CRCW060324K9FKEA
31 1 R30 RES, 1210 750Ω 5% 1/2W VISHAY CRCW1210750RJNEA
32 1 R32 RES, 0603 10k 5% 1/10W NIC NRC06J103TRF
33 1 T1 XFMR, FLYBACK (T201) WURTH ELEKTRONIK 750813002
34 1 U1 IC, TRIAC DIMMABLE OFFLINE LED DRIVER LINEAR TECH. LT3799EMSE
Hardware
2 E4, E5 TURRET MILL-MAX 2308-2-00-80-00-00-07-0
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DEMO MANUAL DC1744A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
scheMAtic DiAgrAM
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DEMO MANUAL DC1744A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2011
LT 0611 REV A • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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