Linear Technology LTC3765 Quick setup guide

1
dc2199aafa
DEMO MANUAL DC2199A-A
DESCRIPTION
LTC3765/LTC3766
360W Isolated Forward Converter
with Synchronous Rectification
Demonstration circuit 2199A-A is a 360W isolated for-
ward converter with synchronous rectification featuring
the LTC3765/LTC3766. It produces a regulated 12V, 30A
output from an input voltage range of 36V to 60V.
This circuit was designed to demonstrate the high levels
of performance, efficiency, and small solution size attain-
able using these parts in an active-clamp-reset forward
converter power supply, suitable for telecom, industrial,
and other applications. It has a 4.7in2solution footprint
area. Synchronous rectification helps to attain an effi-
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
ciency exceeding 96%. Secondary-side control eliminates
complex opto-coupler feedback, providing fast transient
response with minimum output capacitance. For other
output requirements, see the LTC3766 data sheet or
contact the LT C sales.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2199A-A
Specifications are at TA= 25°C
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Input Supply Range 36 60 V
VOUT Output Voltage 11.76 12.0 12.24 V
IOUT Output Current Range, Continuous 200LFM 0 30 A
fSW Switching (Clock) Frequency 200 kHz
VOUT(P-P) Output Ripple VIN = 24V, IOUT = 30A (20MHz BW) 60 mVP-P
IREG Output Regulation Line and Load (36VIN to 60VIN, 0AOUT to 30AOUT) ±0.02 %
POUT/PIN Efficiency (See Figure 3) VIN =48V, IOUT = 30A 96 %
Isolation Basic 1500 VDC
Approximate Solution Size Component Area × Top Component Height 4.7in2× 0.6 Inches

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dc2199aafa
DEMO MANUAL DC2199A-A
OPERATING PRINCIPLES
QUICK START PROCEDURE
The LTC3765 active clamp forward controller and gate
driver is used on the primary and provides start-up, gate
drive, and protection functions. Once start-up is accom-
plished, the LTC3766 high efficiency, secondary-side
synchronous forward controller takes over, and provides
the LTC3765 with timing information and bias power
through a small pulse transformer.
When input voltage is applied, the LTC3765 commences
soft-start of the output voltage. When the output reaches
the RUN threshold, the LTC3766 comes alive and takes
control by sending encoded PWM gate pulses to the
LTC3765 through T2. These pulses also provide primary
bias power efficiently over a wide input voltage range.
The transition from primary to secondary control occurs
at some fraction of the nominal output voltage. From then
on, operation and design is reduced to that of a simple
Demonstration circuit 2199A-A is easy to set up to evalu-
ate the performance of the LTC3765/LTC3766. Refer to
Figure 1 for proper measurement equipment setup and
follow the procedure below:
NOTE:Whenmeasuringtheoutputvoltageripple,caremust
be taken to avoid a long ground lead on the oscilloscope
probe. Measure the output voltage ripple by touching the
probe tip and ground ring directly across the last output
capacitor as shown in Figure 1.
1. Set an input power supply that is capable of 36V to 60V
to 36V. Then turn off the supply.
2. Directanairflowof200LFMacrosstheunitforsustained
operation at full load.
3. Withpower off, connect the supply tothe input terminals
+VIN and –VIN.
a. Input voltages lower than 36V can keep the converter
from turning on due to the undervoltage lockout
feature of the LTC3765/LTC3766.
buckconverter.Secondarycontroleliminatesdelays,tames
large-signal overshoot, and reduces output capacitance
needed to meet transient response requirements.
An optional LC filter stage on the input lowers RMS input
current. The filter must have output impedance that is less
than the converter input impedance to assure stability.
This may require a damping impedance, which is provided
by R1. (See Linear Technology Application Note 19 for a
discussion of input filter stability.) R1 is coupled through
a tiny 2mm × 2mm inductor L1, and provides damping
with arbitrarily low source impedance. For bench testing,
an electrolytic capacitor has been added at the input ter-
minals to provide suitable ripple current capability. The
values selected have a filter resonant frequency that is
below the converter switching frequency, thus avoiding
high circulating currents in the filter.
b. If efficiency measurements are desired, an ammeter
capable of measuring 15ADC or a resistor shunt can
be put in series with the input supply in order to
measure the DC2199A-A’s input current.
c. A voltmeter with a capability of measuring at least
60V can be placed across the input terminals in order
to get an accurate input voltage measurement.
4. Turn on the power at the input.
NOTE: Make sure that the input voltage never ex-
ceeds 60V.
5. Check for the proper output voltage of 12V. Turn off
the power at the input.
6. Once the proper output voltages are established, con-
nect a variable load capable of sinking 30A at 12V to
the output terminals +VOUT and –VOUT. Set the current
for 0A.
a. If efficiency measurements are desired, an ammeter
or a resistor shunt that is capable of handling 30ADC
can be put in series with the output load in order to
measure the DC2199A-A’s output current.

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dc2199aafa
DEMO MANUAL DC2199A-A
QUICK START PROCEDURE
b. Avoltmeter with acapability of measuring at least 12V
can be placed across the output terminals in order
to get an accurate output voltage measurement.
7. Turn on the power at the input.
NOTE. If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
8. Once the proper output voltage is again established,
adjust the load within the operating range and observe
the output voltage regulation, ripple voltage, efficiency
and other desired parameters.
Figure 1. Proper Measurement Equipment Setup
Figure 2. Efficiency and Power Dissipation
IOUT (A)
0
EFFICIENCY? (%)
98
97
95
96
94
92
93
91
90
POWER DISSIPATION (W)
18
16
12
14
10
6
8
4
2
10 205 15
dc2199aa F02
3025
36VIN
48VIN
60VIN
48VIN_PD

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dc2199aafa
DEMO MANUAL DC2199A-A
QUICK START PROCEDURE
Figure 3. Output Ripple at 48VIN and 30AOUT (50mV, 10A, 2µs/DIV, 20MHz)
Figure 4. Transient Response Waveform at 48VIN and 15A to 30A to 15AOUT (10A, 500mV, 200µs/DIV)

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dc2199aafa
DEMO MANUAL DC2199A-A
QUICK START PROCEDURE
Figure 5. Thermal Map, Front Side at 48VIN and 30AOUT (TA= 25°C, 200LFM)
Figure 6. Thermal Map, Back Side at 48VIN and 30AOUT (TA= 25°C, 200LFM)

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dc2199aafa
DEMO MANUAL DC2199A-A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 2 C1, C22 Cap., Alum., Elect., 33µF, 80V, CAP-10X12.5 PANASONIC, EEHZA1K330P
2 5 C2, C3, C4, C5, C6 CAP., X7R, 4.7µF, 100V, 10%, 1210 MURATA, GRM32ER72A475KE14
3 4 C7, C31, C33, C68 CAP., POSCAP, 150µF, 16V, 20%, 7343 PANASONIC, 16TQC150MYF
4 1 C10 CAP., X7R, 2.2nF, 630V, 5%, 1206 MURATA, GRM31A7U2J222JW31
5 1 C11 CAP., X7R, 0.015µF, 25V, 10%, 0603 AVX, 06033C153KAT2A
6 2 C24, C71 CAP., X7R, 1.0µF, 16V, 10%, 0805 MURATA, GRM21BR71C105KA01
7 1 C30 CAP., X7R, 2200pF, 250V, 10%, 1812 MURATA, GA343QR7GD222KW01L
8 1 C34 CAP., X5R, 22µF, 16V, 20%, 1206/1210 MURATA, GRM32ER71C226MEA8L
9 1 C51 CAP., C0G, 470pF, 630V, 5%, 1206 MURATA, GRM31A5C2J471JW01
10 1 C66 CAP., X7R, 0.047µF, 200V, X7R, 10% 1206 MURATA, GRM31CR72D473KW03
11 1 C69 CAP., X7R, 1.5nF, 630V, 5%, 1206 MURATA, GRM31A7U2J152JW31
12 2 C70, C76 CAP., X7R, 3.3nF, 25V, 10%, 0603 AVX, 06033C332KAT2A
13 2 C72, C102 CAP., X7R, 0.1µF, 25V, 10%, 0805 AVX, 08053C104KAT2A
14 4 C55, C73, C80, C119 CAP., X7R, 1nF, 25V, 10%, 0603 MURATA, GRM188R71E102KA01
15 1 C75 CAP., NPO, 100pF, 25V, 5%, 0603 AVX, 06033A101JAT2A
16 1 C77 CAP., X7R, 4.7µF, 25V, 10%, 1206 AVX, 12063C475KAT2A
17 1 C78 CAP., NPO, 0.033µF, 25V, 5%, 0805 TDK, C2012C0G1E333J
18 1 C79 CAP., X7R, 4.7nF, 25V, 10%, 0603 MURATA, GRM188R71E472KA01
19 1 C101 CAP., NPO, 220pF, 25V, 5%, 0603 AVX, 06033A221JAT2A
20 1 C106 CAP., COG, 150pF, 250V, 5%, 0603 TDK, C1608C0G2E151J080AA
21 1 C112 CAP., X7R, 0.22µF, 250V, 10%, 1206/1210 TDK C3225X7R2E224K
22 1 C113 CAP., X7R, 0.033µF, 25V, 10%, 0603 AVX, 06033C333KAT2A
23 1 C118 CAP., NPO, 1500pF, 5%, 0603 AVX, 06033A152JAT2A
24 2 D1, D34 DIODE ULTRA FAST 1A, 200V, SMP VISHAY, ES1PD-M3 / 84A
25 3 D27, D29, D30 DIODE SCHOTTKY 60V, 0.5A, SOT23 DIODES INC, ZHCS506TA
26 1 D40 DIODE, 1N4148WS, SOD323 VISHAY, 1N4148WS-E3-08
27 1 L1 INDUCTOR, 1.0µH, 20% COILCRAFT, XPL2010-102ML
28 1 L2 INDUCTOR, 2.0µH, 20% VISHAY, IHLP4040DZER2R0M11
29 1 L3 INDUCTOR, 3.3µH, 10% COILCRAFT, SER2915L-332KL
30 2 Q8, Q9 MOSFET N-CH 150V, POWERPAK-SO-8 INFINEON, BSC190N15NS3 G
31 4 Q12, Q13, Q14, Q15 MOSFET N-CH 80V, POWERPAK-SO-8 INFINEON, BSC028N06NS3
32 1 Q27 TRANS., NPN 40V, 1A, SOT-89 DIODE INC., FCX491ATA
33 1 Q28 MOSFET, N-CH, SUPER, SOT-6 FAIRCHILD, FDC2512-NL
34 1 Q29 MOSFET, P-CH, IRF6217, POWERPAK-SO-8 IR, IRF6217TRPBF
35 1 R1 RES., CHIP, 0.33, 1/4W, 5%, 2512 PANASONIC, ERJ-1TRQJR33U
36 1 R4 RES., CHIP, 8.2k, 1W, 5%, 2512 PANASONIC, ERJ-1TYJ822U
37 1 R18 RES., CHIP, 102k, 1/8W, 1%, 0805 VISHAY, CRCW0805102KFKEA
38 1 R22 RES., CHIP, 3.74k, 1/16W, 1%, 0603 VISHAY, CRCW06033K74FKEA
39 2 R23, R24 RES., CHIP, 8.2, 1/4W, 5%, 1206 VISHAY, CRCW12068R20JKEA
40 1 R29 RES., CHIP, 100k, 1/8W, 5%, 0805 VISHAY, CRCW0805100KJNEA
41 1 R41 RES., CHIP, 11.5k, 1/16W, 1%, 0603 VISHAY, CRCW060311K5FKEA

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dc2199aafa
DEMO MANUAL DC2199A-A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
42 1 R42 RES., CHIP, 1k, 1/16W, 1%, 0603 VISHAY, CRCW06031K00FKEA
43 1 R46 RES., CHIP, 604, 1/16W, 1%, 0603 VISHAY, CRCW0603604RFKEA
44 2 R51, R52 RES., CHIP, 3.0, 1/4W, 5%, 1206 PANASONIC, ERJ-8GEYJ3R0V
45 1 R53 RES., CHIP, 6.8, 1/2W, 1%, 1206 PANASONIC, ERJ-8RQF6R8V
46 1 R68 RES., CHIP, 2.15k, 1/16W, 1%, 0603 VISHAY, CRCW06032K15FKEA
47 1 R69 RES., CHIP, 46.4k, 1/16W, 1%, 0603 VISHAY, CRCW060346K4FKEA
48 1 R75 RES., CHIP, 215, 1/8W, 1%, 0805 VISHAY, CRCW0805215RFKEA
49 1 R76 RES., CHIP, 4.22, 1/8W, 1%, 0805 VISHAY, CRCW08054R22FKEA
50 1 R84 RES., CHIP, 1.21k, 1/8W, 1%, 0805 VISHAY, CRCW08051K21FKEA
51 4 R101, R148, R149, R151 RES., CHIP, 100, 1/16W, 1%, 0603 VISHAY, CRCW0603100RFKEA
52 1 R109 RES., CHIP, 10k, 1/16W, 1%, 0603 VISHAY, CRCW060310K0FKEA
53 1 R110 RES., CHIP, 1.20, 1/2W, 1%, 1206 SUSUMU, RL1632S-1R20-F
54 1 R114 RES., CHIP, 28.7k, 1/16W, 1%, 0603 VISHAY, CRCW060328K7FKEA
55 1 R117 RES., CHIP, 12.7k, 1/16W, 1%, 0603 VISHAY, CRCW060312K7FKEA
56 1 R118 RES., CHIP, 681k, 1/16W, 1%, 0603 VISHAY, CRCW0603681KFKEA
57 1 R121 RES., CHIP, 133k, 1/16W, 1%, 0603 VISHAY, CRCW0603133KFKEA
58 1 R123 RES., CHIP, 118k, 1/16W, 1%, 0603 VISHAY, CRCW0603118KFKEA
59 1 R125 RES., CHIP, 17.4k, 1/16W, 1%, 0603 VISHAY, CRCW060317K4FKEA
60 1 R136 RES., CHIP, 0.005, 1W, 1%, 1225 SUSUMU, KRL6432D-M-R005-F-T5
61 1 R139 RES., CHIP, 26.7k, 1/16W, 1%, 0603 VISHAY, CRCW060326K7FKEA
62 1 R140 RES., CHIP, 274, 1/8W, 1%, 0805 PANASONIC, ERJ-6ENF2740V
63 1 R150 RES., CHIP, 14.3k, 1/16W, 1%, 0603 VISHAY, CRCW060314K3FKEA
64 1 T1 TRANSFORMER CHAMPS TECH., LT C -PQ26-0402
65 1 T2 TRANSFORMER, 1.25:1 Pulse, PA3493NL
66 1 T3 TRANSFORMER, 1:100, CT02-100 ICE COMPONENTS, CT02-100 = 1:100
67 1 U1 I.C. LTC3765EMSE, MSOP-16PIN LINEAR TECH., LTC3765EMSE#PBF
68 1 U2 I.C. LTC3766EGN, SSOP-GN28 LINEAR TECH., LTC3766EGN#PBF
Additional Demo Board Circuit Components
1 0 C12, C13, C14, C16, C20 CAP., OPT, 0603 OPT
2 0 C8, C9, C18, C19, C103, C111 CAP., OPT, 0603 OPT
3 0 C15, C21, C114 CAP., OPT, 0805 OPT
4 0 C17, C116 CAP., OPT, 1206 OPT
5 0 C23, C25, C26 CAP., OPT, CAP-SVPF-E12 OPT
6 2 C74, C105 CAP, 0Ω, JUMPER 0603 VISHAY, CRCW06030000Z0EA
7 0 D2 DIODE TBD SOD323 OPT
8 0 D4, D35 DIODE OPT, SOD323 OPT
9 0 D28, D37, D38 DIODE OPT, SOT23 OPT
10 0 L4 INDUCTOR, OPT, DO1606T OPT
11 0 Q1, Q2 MOSFET, OPT, SOT23-6 OPT
12 0 Q4 MOSFET, OPT, D-PAK OPT
13 0 Q11, Q23, Q24 MOSFET, OPT, POWERPAK-SO-8 OPT
14 0 R5 RES., OPT, 2512/2010 OPT

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dc2199aafa
DEMO MANUAL DC2199A-A
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
15 13 R6, R7, R8, R9, R49, R103, R111, R112,
R113, R122, R124, R137, R146
RES., CHIP, 0Ω, 0603 VISHAY, CRCW06030000Z0EA
16 0 R10, R13, R14, R15 RES., OPT, 2512 OPT
17 0 R17, R108, R116, R127 RES., OPT, 1206 OPT
18 0 R25, R26, R27, R28, R30, R31, R32, R33,
R34, R35, R43, R106, R107, R119, R120,
R126, R138, R147
RES., OPT, 0603 OPT
19 1 R77 RES., CHIP, 0, 1/8W, 0805 VISHAY, CRCW08050000Z0EA
20 1 R102 RES., CHIP, 0Ω, 1225 TEPRO,RN5326
21 1 R115 RES., CHIP, 0, 1/4W, 1206 VISHAY, CRCW12060000Z0EA
22 0 R152 RES., OPT, 0805 OPT
23 0 U3 I.C. OPT, SO16 OPT
Hardware: For Demo Board Only
1 4 E1, E2, E3, E4 TESTPOINT, TURRET, .094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 3 E5, E6, E7 TESTPOINT, TURRET, .061" MILL-MAX, 2308-2-00-80-00-00-07-0
3 0 J1 HEADER, OPT, 2×7PIN, 0.079CC OPT, MOLEX, 87331-1420
4 2 J3, J4 STUD, TEST PIN PEM, KFH-032-10
5 4 J3, J4(2 EACH) NUT, BRASS, #10-32 ANY #10-32
6 2 J3, J4 WASHER, STAR #10 BRASS NICKEL ANY, #10EXT BZ TN
7 2 J3, J4 Ring, Lug Ring # 10 KEYSTONE, 8205
8 0 TP1-TP6 PAD-SMD PAD-SMD
9 4 (STAND-OFF) STAND-OFF, NYLON 0.25" KEYSTONE, 8831 (SNAP ON)
10 1 FAB, PRINTED CIRCUIT BOARD DEMO CIRCUIT 2199A
PARTS LIST

9
dc2199aafa
DEMO MANUAL DC2199A-A
Simplified Schematic (without Unneeded Components)
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
+VOUT
36V-60VIN
-VOUT
1210
1812
0805
0805
0805
1210
0805
0805
1210
0805
12VOUT / 30A
COG
7343
1.25T 1T
1/4W = 1206, 1W = 2512. Unless otherwise specified: All resistors are in ohms 0603. All capacitors are in microfarads 0603. All capacitors are 25V. 1/16W = 0402, 1/10W = 0603, 1/8W = 0805,
NOTE: 4.7uF 100V MURATA, GRM32ER72A475KE14 (X7R 1210) 4.7uF 25V AVX, 12063C475KAT2A (X7R 1206) 22uF 16V MURATA, GRM32ER71C226MEA8L (1210 X5R) 2.2nF 250V Murata GA343QR7GD222KW01L (X7R 1812) 150uF 16V PANASONIC, 16TQC150MYF 33uF 80V PANASONIC, EEHZA1K330P (10x12.5mm) L2 Vishay IHLP4040DZER2R0M11 L3 Coilcraft SER2915L-332KL 0.005 ohm Susumu KRL6432D-M-R005-F-T5 (1225) R110 SUSUMU, RL1632S-1R20-F (1206) T1 Champs, LTC-PQ26-0402 T2 Pulse, PA3493NL
0805
0805
0805
0805
1206
1206
0805
1210
1/2W
ND
VCP
FG
FG
+VOUT
+VOUT
VIN
IS+
-VIN
IS+
-VOUT
UV
VIN
RS-
-VIN
ND
-VOUT +VOUT
PGNDP
SGNDP
SGNDP
SGND PGND
SGND
SGND
SGND
PGND
PSS
SGND
SGNDP
SGNDP
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Friday, October 31, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN28
DC2199A
WITH DIRECT FLUX LIMIT
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Friday, October 31, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN28
DC2199A
WITH DIRECT FLUX LIMIT
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Friday, October 31, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN28
DC2199A
WITH DIRECT FLUX LIMIT
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 8-18-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 8-18-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 8-18-14
__
Q15 BSC028N06NS3Q15 BSC028N06NS3
Q12 BSC028N06NS3Q12 BSC028N06NS3
R151
100
R151
100
FCX491A
Q27
FCX491A
Q27
1
3 2
C119
1nF
C119
1nF
C34
22uF
16V C34
22uF
16V
C10 2.2nF 630V 1206 C10 2.2nF 630V 1206
Q24 OPTQ24 OPT
C102 0.1uF C102 0.1uF
LTC3766EGN28
U2
LTC3766EGN28
U2
ITH
7
FG 2
SW 23
FB 6
GND
14
IS+ 18
IS- 17
SG 1
VCC 28
PT+
26
PT-
25
REGSD
16
FS/SYNC
15
SS
9
MODE
4
PGND
27
VIN 22
NDRV 21
IPK
10
PHASE
5
VS+ 12
VS- 13
VSOUT
11
RUN
8FGD/SWB 20
VSEC 3
SGD
19
VAUX 24
T2
TRANS-PA3493NL
T2
TRANS-PA3493NL
3 1 6
4
R148
100
R148
100
R101
100
R101
100
R69
46.4K
R69
46.4K
Q14 BSC028N06NS3 Q14 BSC028N06NS3
Q11 OPTQ11 OPT
C73
1nF
C73
1nF
D34
ES1PD
D34
ES1PD
C69
1.5nF
630V
C69
1.5nF
630V
T3
CT02-100
T3
CT02-100
1 2
34
C72
0.1uF
C72
0.1uF
+VIN+VIN
R117 12.7K R117 12.7K
C3,4,5,6 4x4.7uF
100V
C3,4,5,6 4x4.7uF
100V
D27
ZHCS506
D27
ZHCS506
13
R68 2.15K R68 2.15K
C76 3.3nF C76 3.3nF
Q29
IRF6217
Q29
IRF6217
-VIN-VIN
R139 26.7K R139 26.7K
+
C1,22
2x33uF
80V
+
C1,22
2x33uF
80V
C55
1nF
C55
1nF
Q13 BSC028N06NS3 Q13 BSC028N06NS3
C66 47nF
200V
1206
C66 47nF
200V
1206
Q8 BSC190N15NS3Q8 BSC190N15NS3
C75
100pF
C75
100pF
T1
LTCP26-0402
T1
LTCP26-0402
126
92 14 8
10
13
3
5
R42
1K
R42
1K
Q23 OPTQ23 OPT
R114
28.7K
R114
28.7K
R29
100K
R29
100K
C80 1nF C80 1nF
R149
100
R149
100
R23,24 2x8.2 1206 R23,24 2x8.2 1206
R18 102K R18 102K
R4
8.2K
2512
R4
8.2K
2512
R41
11.5K
R41
11.5K
R121 133K R121 133K
D30
ZHCS506
D30
ZHCS506
13
R123
118K
R123
118K
C71 1uF
16V
C71 1uF
16V
R84
1.21K
R84
1.21K
R51,52 2x3.0 1206 R51,52 2x3.0 1206
R118 681K R118 681K
L2
2.0uH
L2
2.0uH
D1 ES1PD D1 ES1PD
1 2
C11
15nF
C11
15nF
R46 604 R46 604
C30
2.2nF 250V
C30
2.2nF 250V
LTC3765EMSE
U1
LTC3765EMSE
U1
NDRV 14
VCC
3
PG 2
IN+ 15
IN- 16
RUN
12
AG 4
DELAY
6
IS- 7
GND
17
IS+ 8
FS/UV
10
SSFLT
13
PGND
1
GND2
9
RCORE
11
ISMAG
5
C101 220pF C101 220pF
C77
4.7uF
C77
4.7uF
R76 4.22 R76 4.22
R1
0.33 2512
R1
0.33 2512
R110 1.20 1206 R110 1.20 1206
R125 17.4K R125 17.4K C79
4.7nF
C79
4.7nF
Q28
FDC2512
Q28
FDC2512
+
C7,31,33,68
4x150uF 16V
+
C7,31,33,68
4x150uF 16V
C51
470pF
630V
1206
C51
470pF
630V
1206
C78
33nF
C78
33nF
C113 33nF C113 33nF
C106 150pF 250V C106 150pF 250V
L1
1.0uH
L1
1.0uH
R75
215
R75
215
R136 0.005 1225/2512 R136 0.005 1225/2512
C112 0.22uF
200V
C112 0.22uF
200V
C70
3.3nF
C70
3.3nF
D29
ZHCS506
D29
ZHCS506
13
R140 274 1/8W R140 274 1/8W
C118
1.5nF
C118
1.5nF
R22
3.74K
R22
3.74K
L3
3.3uH
L3
3.3uH
R109 10K R109 10K
R53 6.8 1206 R53 6.8 1206
Q9 BSC190N15NS3 Q9 BSC190N15NS3
C24 1uF 16V C24 1uF 16V
C2
4.7uF
100V
C2
4.7uF
100V
R150
14.3K
R150
14.3K

10
dc2199aafa
DEMO MANUAL DC2199A-A
SCHEMATIC DIAGRAM
Full Schematic, Page 1
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
+VOUT
36V-60VIN
-SENSE +SENSE -VOUT
1210 1210 1210
1210
1812
7343
7343
0805
0805
0805
0805
1210
0805
0805
1210
0805
12VOUT / 30A
COG
7343
1206
1.25T 1T
1/4W = 1206, 1W = 2512. Unless otherwise specified: All resistors are in ohms 0603. All capacitors are in microfarads 0603. All capacitors are 25V. 1/16W = 0402, 1/10W = 0603, 1/8W = 0805,
NOTE: 4.7uF 100V MURATA, GRM32ER72A475KE14 (X7R 1210) 4.7uF 25V AVX, 12063C475KAT2A (X7R 1206) 22uF 16V MURATA, GRM32ER71C226MEA8L (1210 X5R) 2.2nF 250V Murata GA343QR7GD222KW01L (X7R 1812) 150uF 16V PANASONIC, 16TQC150MYF 33uF 80V PANASONIC, EEHZA1K330P (10x12.5mm) L2 Vishay IHLP4040DZER2R0M11 L3 Coilcraft SER2915L-332KL 0.005 ohm Susumu KRL6432D-M-R005-F-T5 (1225) R110 SUSUMU, RL1632S-1R20-F (1206) T1 Champs, LTC-PQ26-0402 T2 Pulse, PA3493NL
1206
0805
0805
0805
0805
1206
1206
1206 7343
0805
ITH-
1210
RUN
1/2W
AG
AG1
ND
VS+
VS-
VCP
VCC
FG
FG
+VOUT
+VOUT
VIN
RUN
IS+
-VIN
IS+
-VOUT
UV
VPK
VIN
AS
RS-
-VIN
RUN
ND
RS+RS-
VAUX
RS+RS-
SWB
VCC
SW
-VOUT
AS
-VOUT +VOUT
VCC
VA
PGND
PGNDP
SGNDP
SGNDP
SGND PGND
SGND
PGND
SGND
SGND
PGND
FG
PT-
PSS
SSS SYNC ITH
SGND
SGNDP
SGNDP
VCC
CLAMP
AG
AG1
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Wednesday, October 29, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN
DC2199A
WITH DIRECT FLUX LIMIT
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Wednesday, October 29, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN
DC2199A
WITH DIRECT FLUX LIMIT
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
Wednesday, October 29, 2014
12
ACTIVE CLAMP FORWARD CONVERTER
LT
DAVID B.
N/A
LTC3765EMSE / LTC3766EGN
DC2199A
WITH DIRECT FLUX LIMIT
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 10-29-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 10-29-14
__
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
DAVID B.PRODUCTION
2 10-29-14
__
R137
0
R137
0
Q12 BSC028N06NS3Q12 BSC028N06NS3
4
5
23 678
1
R52 3.0 1206 R52 3.0 1206
C5
100V
4.7uF
C5
100V
4.7uF
R122
0
R122
0
R111
0
R111
0
C10 2.2nF 630V 1206 C10 2.2nF 630V 1206
R146
0
R146
0
C34
22uF
16V C34
22uF
16V
R106 OPT R106 OPT
C119
1nF
C119
1nF
FCX491A
Q27
FCX491A
Q27
1
3 2
R151
100
R151
100
+
C31 150uF
16V
+
C31 150uF
16V
Q15 BSC028N06NS3Q15 BSC028N06NS3
4
5
23 678
1
R138 OPT R138 OPT
R147
OPT
R147
OPT
R69
46.4K
R69
46.4K
R101
100
R101
100
R148
100
R148
100
T2
TRANS-PA3493NL
T2
TRANS-PA3493NL
3 1 6
4
LTC3766EGN
U2
LTC3766EGN
U2
ITH
7
FG 2
SW 23
FB 6
GND
14
IS+ 18
IS- 17
SG 1
VCC 28
PT+
26
PT-
25
REGSD
16
FS/SYNC
15
SS
9
MODE
4
PGND
27
VIN 22
NDRV 21
IPK
10
PHASE
5
VS+ 12
VS- 13
VSOUT
11
RUN
8FGD/SWB 20
VSEC 3
SGD
19
VAUX 24
+
C23
OPT
+
C23
OPT
C102 0.1uF C102 0.1uF
Q24 OPT Q24 OPT
4
5
23 678
1
C105
0
C105
0
T3
CT02-100
T3
CT02-100
1 2
34
C69
1.5nF
630V
C69
1.5nF
630V
Q11 OPTQ11 OPT
4
5
2 3 678
1
Q14 BSC028N06NS3 Q14 BSC028N06NS3
4
5
23 678
1
D34
ES1PD
D34
ES1PD
J3J3
C73
1nF
C73
1nF
E4
-
E4
-
C76 3.3nF C76 3.3nF
R107
OPT
R107
OPT
Q31
OPT
Q31
OPT
1
32
R68 2.15K R68 2.15K
D27
ZHCS506
D27
ZHCS506
13
E6E6
R115 0 1/4W R115 0 1/4W
R127 OPT 1/4W R127 OPT 1/4W
R124 0 R124 0
C3
4.7uF
100V
C3
4.7uF
100V
C74 0 C74 0
R117 12.7K R117 12.7K
D40
1N4148WS
D40
1N4148WS
1 2
E1
+VIN
E1
+VIN
C72
0.1uF
C72
0.1uF
C55
1nF
C55
1nF
+
C1
33uF
80V
+
C1
33uF
80V
R8 0 R8 0
Q29
IRF6217
Q29
IRF6217
4
15
2
3
6
7
8
R139 26.7K R139 26.7K
C6
4.7uF
100V
C6
4.7uF
100V
E2
-VIN
E2
-VIN
J4J4
R77
0
R77
0
R103
0
R103
0
Q13 BSC028N06NS3 Q13 BSC028N06NS3
4
5
23 678
1
+
C22
33uF
80V
+
C22
33uF
80V
+
C26
+
C26
C9 OPT C9 OPT
R49
0
R49
0
C66 47nF
200V
1206
C66 47nF
200V
1206
R42
1K
R42
1K
R7 0 0603 R7 0 0603
Q8 BSC190N15NS3Q8 BSC190N15NS3
4
5
2 3 678
1
T1
LTCP26-0402
T1
LTCP26-0402
126
92 14 8
10
13
3
5
C75
100pF
C75
100pF
R6
0
0603 R6
0
0603
Q23 OPT Q23 OPT
4
5
23 678
1
R119
OPT
R119
OPT
R41
11.5K
R41
11.5K
C111
OPT
C111
OPT
R4
8.2K
2512
R4
8.2K
2512
R18 102K R18 102K
R24
8.2 1206
R24
8.2 1206
R149
100
R149
100
C80 1nF C80 1nF
R29
100K
R29
100K
R108
OPT
R108
OPT
R114
28.7K
R114
28.7K
Q3 OPT Q3 OPT
3
1
2
R113
0
R113
0
C103
OPT
C103
OPT
R23
8.2 1206
R23
8.2 1206
R118 681K R118 681K
R51 3.0 1206 R51 3.0 1206
R84
1.21K
R84
1.21K
C71 1uF
16V
C71 1uF
16V
R123
118K
R123
118K
+
C68
150uF 16V
+
C68
150uF 16V
D30
ZHCS506
D30
ZHCS506
13
R121 133K R121 133K
C30
2.2nF 250V
C30
2.2nF 250V
R126
OPT
R126
OPT
R46 604 R46 604
C11
15nF
C11
15nF
D1 ES1PD D1 ES1PD
1 2
L2
2.0uH
L2
2.0uH
R109 10K R109 10K
C8
OPT
C8
OPT
R3 OPT R3 OPT
C77
4.7uF
C77
4.7uF
R116
OPT 1206
R116
OPT 1206
D28 OPT D28 OPT
13
C101 220pF C101 220pF
LTC3765EMSE
U1
LTC3765EMSE
U1
NDRV 14
VCC
3
PG 2
IN+ 15
IN- 16
RUN
12
AG 4
DELAY
6
IS- 7
GND
17
IS+ 8
FS/UV
10
SSFLT
13
PGND
1
GND2
9
RCORE
11
ISMAG
5
R112
0
R112
0
C79
4.7nF
C79
4.7nF
R125 17.4K R125 17.4K
R110 1.20 1206 R110 1.20 1206
R1
0.33 2512
R1
0.33 2512
R76 4.22 R76 4.22
R75
215
R75
215
+
C25
+
C25
E3
+
E3
+
L1
1.0uH
L1
1.0uH
R43 OPT R43 OPT
C106 150pF 200V C106 150pF 200V
C113 33nF C113 33nF
Q28
FDC2512
Q28
FDC2512
3
4 1
2
5
6
C78
33nF
C78
33nF
C51
470pF
630V
1206
C51
470pF
630V
1206
+
C7
150uF 16V
+
C7
150uF 16V
R5
OPT 2512
R5
OPT 2512
R102
0
1225
R102
0
1225
R140 274 1/8W R140 274 1/8W
D29
ZHCS506
D29
ZHCS506
13
C70
3.3nF
C70
3.3nF
C112 0.22uF
200V
C112 0.22uF
200V
C4 100V 4.7uF C4 100V 4.7uF
R136 0.005 1225/2512 R136 0.005 1225/2512
R10
OPT 2512
R10
OPT 2512
R2
OPT
R2
OPT
R53 6.8 1206 R53 6.8 1206
E5E5
L3
3.3uH
L3
3.3uH
R22
3.74K
R22
3.74K
R120
OPT
R120
OPT
C118
1.5nF
C118
1.5nF
R150
14.3K
R150
14.3K
Q9 BSC190N15NS3 Q9 BSC190N15NS3
4
5
2 3 678
1
R9
0
R9
0
E7E7
C2
4.7uF
100V
C2
4.7uF
100V
+
C33 150uF 16V
+
C33 150uF 16V
C24 1uF 16V C24 1uF 16V