Linear Technology DC1739A-B Quick setup guide

1
dc1739afb
DEMO MANUAL DC1739A-B
DESCRIPTION
LTC3765/LTC3766
150W High Efficiency Active Clamp
Forward Converter
Demonstration circuit 1739A-B is a 150W isolated forward
converter with synchronous rectification featuring the
LTC3765/LTC3766.
This circuit demonstrates a high level of performance, ef-
ficiency, and small solution size attainableusing these parts
in an active-clamp-reset forward converter power supply.
It operates at 240kHz and produces a regulated 12V, 12.5A
output from an input voltage range of 18V to 72V, making
it well suited for telecom, industrial, and other applica-
tions. It has an eighth-brick footprint size of 0.90" ×2.3". L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation and Direct Flux Limit is a trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
OPERATING PRINCIPLES
Synchronous rectification helps to attain efficiency ex-
ceeding 94%. Secondary-side control eliminates complex
opto-coupler feedback, providing fast transient response
with minimum output capacitance. The proprietary Direct
Flux Limit™
scheme guarantees no transformer saturation.
For other output requirements, see the LTC3766 data sheet
or contact the LTC factory.
Design files for this circuit board are available at
http://www.linear.com/demo
(TA= 25°C)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN Input Supply Range 18 72 V
VOUT Output Voltage 12.0 V
IOUT Output Current Range, Continuous 200LFM 0 11 A
IOUT Output Current , Peak 200LFM 12.5 A
fSW Switching (Clock) Frequency 240 kHz
VOUT P-P Output Ripple VIN = 48V, IOUT = 12A (20MHz BW) 60 mVP–P
IREG Output Regulation Line and Load (18-72VIN, 0-12AOUT) ±0.08 %
POUT/PIN Efficiency (see Figure 3) VIN = 48V, IOUT = 10A 93.6 %
Isolation Basic 1500 VDC
Approximate Size Component Area ×Top Component Height 2.3 ×0.9 ×0.47 Inches
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 ac-
complished, 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 secondary bias
source reaches the undervoltage threshold, the LTC3766
comes alive and takes control by sending encoded PWM
gate pulses to the LTC3765 through T3. These pulses also
provide primary bias power efficiently over a wide input
voltage range.
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dc1739afb
DEMO MANUAL DC1739A-B
QUICK START PROCEDURE
Demonstration circuit 1739 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.When measuring theoutput voltageripple, 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 18V to 72V
to 18V. Then turn off the supply.
2. Directan airflow of 200LFM across the unit for sustained
operation at full load.
3. Withpower off,connect thesupply tothe inputterminals
+VIN and –VIN.
a. Input voltages lower than 18V can keep the converter
from turning on due to the undervoltage lockout
feature of the LTC3765/LTC3766.
b. If efficiency measurements are desired, an ammeter
capable of measuring 10ADC or a resistor shunt can
be put in series with the input supply in order to
measure the DC1739A-B’s input current.
c. A voltmeter with a capability of measuring at least
72V can be placed across the input terminals in order
to get an accurate input voltage measurement.
The transition from primary to secondary control occurs
at some fraction of the nominal output voltage. From then
on, operation and design is simplified to that of a simple
buck converter. Secondary control eliminatesdelays, 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 stabil-
ity. This may require a damping impedance. (See Linear
OPERATING PRINCIPLES
Technology Application Note AN19 for a discussion of
input filter stability.) A source with a 300mΩ or higher ESR
at the filter resonant frequency (~100kHz) is one way of
providing damping for the filter elements provided on the
DC1739A-B. For bench testing, an electrolytic capacitor
has been added at the input terminals to provide suitable
damping and ripple current capability. The values selected
have a filter resonant frequency that is below the converter
switching frequency, thus avoiding high circulating cur-
rents in the filter.
4. Turn on the power at the input.
NOTE. Make sure that the input voltage never exceeds 75V.
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 12.5A at 12V to
the output terminals +VOUT and –VOUT. Set the current
for 0A.
a. If efficiency measurements aredesired,an ammeteror
a resistor shunt that is capable of handling 12.5ADC
can be put in series with the output load in order to
measure the DC1739A-B’s output current.
b. A voltmeter with a capability ofmeasuring 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.
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dc1739afb
DEMO MANUAL DC1739A-B
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
dc1739a F02
0
2
4
6
8
10
12
14
90
91
92
93
94
95
2 4 6 8 10 12
POWER DISSIPATION (W)
EFFICIENCY ( %)
IOUT (A)
PD, 48VIN
PD, 24VIN
Eff, 48VIN
Eff, 24VIN
DC1739A-B Efficiency
Figure 2. Efficiency and Power Dissipation
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dc1739afb
DEMO MANUAL DC1739A-B
QUICK START PROCEDURE
Figure 3. Output Ripple at 48VIN and 11AOUT (50mV, 2μs/DIV, 20MHz)
Figure 4. Transient Response Waveform at 48VIN and 6 – 12AOUT (5A, 500mV, 100μs/DIV)
IOUT
VOUT
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dc1739afb
DEMO MANUAL DC1739A-B
Figure 5. Thermal Map, Frontside at 48VIN and 11AOUT (TA= 25°C, 200LFM)
Figure 6. Thermal Map, Backside at 48VIN and 11AOUT (TA= 25°C, 200LFM)
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dc1739afb
DEMO MANUAL DC1739A-B
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP., AL., TH, 33μF, 100V, ME-PX series SUNCON, 100ME33PX
2 4 C2, C3, C4, C5 CAP., X7R, 2.2μF, 100V, 20%, 1210 MURATA, GRM32ER72A225MA35
3 1 C6 CAP., C0G, 47pF, 200V, 5%, 1206 AVX, 12062A470JAT2A
4 2 C8, C9 CAP., POSCAP, 68μF, 16V, 20%, 7343 SANYO, 16TQC68M
5 1 C10 CAP., X7R, 1.0nF, 630V, 10%, 1206 MURATA, GRM31A7U2J102J
6 2 C11, C12 CAP., X7R, 22μF, 16V, 1210 MURATA, GRM32ER71C226ME20
7 1 C13 CAP., X7R, 1.0μF, 100V, 10%, 1206 MURATA, GRM31CR72A105KA01
8 1 C14 CAP., X7R, 0.1μF, 250V, 10%, 1206 MURATA, GRM31CR72E104KW03
9 1 C16 CAP., C0G, 1000pF, 25V, 5%, 0402 TDK, C1005C0G1E102J
10 3 C17, C20, C35 CAP., X7R, 0.1μF, 25V, 10%, 0603 AVX, 06033C104KAT2A
11 1 C18 CAP., C0G, 470pF, 25V, 5%, 0603 AVX, 06033A471JAT2A
12 2 C21, C23 CAP., X7R, 1.0uF, 16V 10%, 0805 MURATA, GRM21BR71C105KA01L
13 1 C22 CAP., C0G, 220pF, 25V, 5%, 0603 AVX, 06033A221JAT2A
14 1 C24 CAP., X7R, 2200pF, 250V, 10%, 1812 MURATA, GA343QR7GD222KW01L
15 1 C25 CAP., COG, 0.033μF, 25V, 5%, 0805 TDK, C2012C0G1E333J
17 1 C27 CAP., X7R, 10μF, 16V, 1206 MURATA, GRM31CR61C106MA88
18 1 C28 CAP., X7R, 0.010μF, 50V, 10%, 0603 AVX, 06035C103KAT2A
19 1 C29 CAP., X7R, 0.033μF, 25V, 10%, 0603 AVX, 06033C333KAT2A
20 3 C30, C31, C37 CAP., C0G, 1000pF, 25V, 5%, 0603 AVX, 06033A102JAT2A
21 1 C32 CAP., C0G, 47pF, 25V, 5%, 0603 AVX, 06033A470JAT2A
22 1 C33 CAP., C0G, 2200pF, 25V, 5%, 0603 TDK, C1608C0G1E222J
24 2 D1, D4 DIODE ULTRA FAST 1A 200V SMP VISHAY, ES1PD-M3 / 84A
25 2 D3, D5 DIODE SCHOTTKY 40V 0.4A SOD323 DIODES INC., ZHCS400TA
26 1 L1 INDUCTOR, 1.5μH 20% VISHAY, IHLP2525EZER1R5M01
27 1 L4 INDUCTOR, 8.0μH PULSE PA2729.802NL
28 1 Q1 MOSFET, N-CH 120V POWERPAK-SO-8 FAIRCHILD, FDMS86201
29 1 Q3 MOSFET, N-CH 80V POWERPAK-SO-8 FAIRCHILD, FDMS86322
30 1 Q4 MOSFET, N-CH 150V POWERPAK-SO-8 FAIRCHILD, FDMS86200
31 1 Q5 MOSFET, P-CH, IRF6217, SO-8 IR, IRF6217TR
32 1 Q6 MOSFET, N-CH, SUPER SOT-6 FAIRCHILD, FDC2512-NL
33 1 Q7 Transistor, NPN, SOT23 DIODES, FMMT491A
34 1 Q8 Transistor, NPN, SOT323 DIODES, MMST3904
35 1 R1 RES., CHIP, 51.1, 1/4W, 1%, 1206 VISHAY, CRCW120651R1FKEA
36 2 R4, R5 RES., CHIP, 68.1k, 1/4W, 1%, 1206 VISHAY, CRCW120668K1FKEA
37 1 R7, R37 RES., CHIP, 909, 1/8W, 1%, 0805 VISHAY, CRCW0805909RFKEA
39 1 R10 RES., CHIP, 0.004, 1W, 1%, 2512 Panasonic, ERJ-M1WTF4M0U
40 1 R11 RES., CHIP, 75, 1/8W, 1%, 0805 VISHAY, CRCW080575R0FKEA
42 1 R14 RES., CHIP, 0.006, 1W, 1%, 2512 Panasonic, ERJ-M1WSF6M0U
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
44 1 R17 RES., CHIP, 61.9k, 1/8W, 1%, 0805 VISHAY, CRCW080561K9FKEA
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DEMO MANUAL DC1739A-B
PARTS LIST
45 1 R18 RES., CHIP, 100k, 1/8W, 5%, 0805 VISHAY, CRCW0805100KJNEA
46 4 R19, R20, R23, R24 RES., CHIP, 100, 1/32W, 1%, 0402 VISHAY, CRCW0402100RFKEA
47 1 R22 RES., CHIP, 1.82k, 1/4W, 1%, 1206 VISHAY, CRCW12061K82FKEA
48 1 R25 RES., CHIP, 10k, 1/16W, 1%, 0603 VISHAY, CRCW060310K0FKEA
49 1 R27 RES., CHIP, 0.750, 1/8W, 1%, 0805 SUSUMU, RL1220S-R75-F
50 1 R29 RES., CHIP, 19.1k, 1/16W, 1%, 0603 VISHAY, CRCW060319K1FKEA
51 1 R35 RES., CHIP, 1.82k, 1/16W, 1%, 0603 VISHAY, CRCW06031K82FKEA
52 1 R36 RES., CHIP, 11.5k, 1/16W, 1%, 0603 VISHAY, CRCW060311K5FKEA
53 2 R38, R39 RES., CHIP, 100, 1/16W, 1%, 0603 VISHAY, CRCW0603100RFKEA
55 1 R41 RES., CHIP, 4.12k, 1/16W, 1%, 0603 VISHAY, CRCW06034K12FKEA
56 1 R44 RES., CHIP, 56.2k, 1/16W, 1%, 0603 VISHAY, CRCW060356K2FKEA
57 1 R46 RES., CHIP, 60.4k, 1/16W, 1%, 0603 VISHAY, CRCW060360K4FKEA
58 1 R47 RES., CHIP, 15.0k, 1/16W, 1%, 0603 VISHAY, CRCW060315K0FKEA
59 1 R48 RES., CHIP, 4.99k, 1/16W, 1%, 0603 VISHAY, CRCW06034K99FKEA
60 1 R49 RES., CHIP, 1.87k, 1/16W, 1%, 0603 VISHAY, CRCW06031K87FKEA
61 1 R50 RES., CHIP, 604, 1/16W, 1%, 0603 VISHAY, CRCW0603604RFKEA
62 1 R51 RES., CHIP, 13.3k, 1/16W, 1%, 0603 VISHAY, CRCW060313K3FKEA
63 1 R52 RES., CHIP, 22k, 1/16W, 5%, 0603 VISHAY, CRCW060322KJNEA
64 1 R53 RES., CHIP, 8.25k, 1/16W, 1%, 0603 VISHAY, CRCW06038K25FKEA
65 1 R56 RES., CHIP, 1.00k, 1/16W, 1%, 0603 VISHAY, CRCW06031K00FKEA
66 1 T1 TRANSFORMER, 4T:4T:4T PULSE, PA0801NL
67 1 T3 TRANSFORMER, 1.25T:1T PULSE, PA3493NL
68 1 U1 I.C. LTC3765EMSE, MSOP-16PIN LINEAR TECH., LTC3765EMSE
69 1 U2 I.C. LTC3766EGN28, SSOP-GN28 LINEAR TECH., LTC3766EGN
Additional Demo Board Circuit Components
70 0 C7 CAP., OPT, 0805
71 0 C15 CAP., OPT, 0603
72 0 C36 CAP., OPT, 0402
16 1 C26 0Ω Jumper 0603 VISHAY, CRCW06030000Z0EA
72 0 C34 CAP., OPT, 1206
73 0 D6 DIODE OPT SOT23
74 0 L5 INDUCTOR, OPT 1608
75 0 Q2 MOSFET OPT POWERPAK-SO-8
0 Q8 TRANSISTOR OPT NPN SOT323
38 8 R9, R21, R30-R33, R45, R54 0Ω Jumper 0402 VISHAY, CRCW04020000Z0ED
76 0 R12, R13, R28, R43 RES., OPT, 0402
77 0 R15, R26, R42 RES., OPT, 0603
54 1 R40 0Ω Jumper 0603 VISHAY, CRCW06030000Z0EA
Hardware For Demo Board Only
78 4 E1, E2, E3, E4 TESTPOINT, TURRET, .090" pbf MILL-MAX, 2501-2-00-80-00-00-07-0
79 4 J1, J2, J3, J4 Connector, Banana Jack KEYSTONE, 575-4
80 4 MTGS at 4 Corners STANDOFF, NYLON .5 1/2" KEYSTONE, 8833(SNAP-ON)
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dc1739afb
DEMO MANUAL DC1739A-B
SIMPLE SCHEMATIC DIAGRAM
5 5
4 4
3
3
2 2
1 1
DD
C C
B B A A
12V / 12.5A
Fsw=240KHz
4T
1T1.25T
+VOUT
4T
-VOUT
4T
-VIN +VIN
Unless otherwise specified: All resistors are in ohms 0603. All capacitors are in microfarads 0603. All capacitors are 25V. 1/16W = 0603, 1/8W = 0805, 1/4W = 1206.
18 to 72 VIN
NOTE: 2.2uF 100V Murata GRM32ER72A225MA35 (X7R 1210) 22uF 16V Murata GRM32ER61C226ME20 (X7R 1210) 2.2nF 250V Murata GA343QR7GD222KW01L (X7R 1812) 68uF 16V Sanyo 16TQC68M 33uF 100V Suncon 100ME33PX (10x12mm) L1 Vishay IHLP2525EZER1R5M01 L4 Pulse PA2729.802NL T1 PA0801NL T3 PA3493NL
VCC
RS+
+VOUT
-VOUT
FG
VIN
-VOUT
VIN
VCC
+VOUT
+VOUT
AS
-VOUT
-VOUT
RS+RS-
FG
AS
RS-
R41 4.12K
C13
1.0uF 100V 1210
R29
19.1K
C31 1nF
R44 56.2K
R1 51.1
1206
R46
60.4K R47
15.0K
C21 1uF 0805
C23
1uF 0805
C30 1nF
R10
0.004 2512
R24
100 0402
C28 10nF
C37
1.0nF
C3,C4,C5 2.2uF x3
100V 1210
T3
3
1 6
4
R20
100
Q5
IRF6217 C35
0.1uF
C17
0.1uF
R52
22K
R23
100 0402
R53
8.25K
R19 100
C32
47pF
R49 1.87K
C18
470pF
Q1 FDMS86201
R36
11.5K
R38 100
+
C8,C9
68uF x2
16V
LTC3765EMSE
U1
14
3
2
15
16
12
4
6 7
17
8
10
13
1
9
11 5
NDRV
VCC
PG
IN+
IN-
RUN
AG
DELAY IS-
GND
IS+
FS/UV
SSFLT
PGND
GND2
GAMSIEROCR
C10
1nF
630V
1206
D3 ZHCS400
D1
ES1PD
R7
909
0805
C16
1nF
Q4
FDMS86200
C2 2.2uF 100V 1210
T1
7 2
3
11
4
5
R4,R5 68.1K x2 = 34K
1206
R18 100K
0805
+
C1 33uF
100V
L1
1.5uH
C24
2.2nF 250V 1812
R56
1.00K
C29 33nF
FMMT491A
Q7
R27 0.75 0805
R51 13.3K C33
2.2nF
C22 220pF
R37 909
0805
LTC3766EGNU2
7
2
23
6
14
18
17
1
28
26
25
16
15
9
4
27
22
21
10
5
12
13
11
820
3
19
24
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+ PT-
REGSD
FS/SYNC
SS
MODE
PGND
VIN
NDRV
IPK
PHASE
VS+
VS-
VSOUT
RUN FGD/SWB
VSEC
SGD
VAUX
D4 ES1PD
R11 75
0805
Q6
FDC2512
R22
1.82K
1206
R39
100
R17
61.9K
0805
L4
8.0uH
2 1
Q3
FDMS86322
D5
ZHCS400
R14 0.006
2512
R48
4.99K
C6
47pF
200V 1206
C20
0.1uF
C27
10uF
1206 16V
R25
10K
C25
33nF
COG 0805
R35
1.82K
C11,C12 22uF x2 16V 1210
C14 0.1uF 1206
R50 604
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dc1739afb
DEMO MANUAL DC1739A-B
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.
FULL SCHEMATIC DIAGRAM
5 5
4 4
3
3
2 2
1 1
DD
C C
B B A A
Unless otherwise specified: All resistors are in ohms 0603. All capacitors are in microfarads 0603. All capacitors are 25V. 1/16W = 0603, 1/8W = 0805, 1/4W = 1206.
4T
4T
1.25T 1T
4T
Fsw=240KHz
12V / 12.5A
NOTE: 2.2uF 100V Murata GRM32ER72A225MA35 (X7R 1210) 22uF 16V Murata GRM32ER61C226ME20 (X7R 1210) 2.2nF 250V Murata GA343QR7GD222KW01L (X7R 1812) 68uF 16V Sanyo 16TQC68M 33uF 100V Suncon 100ME33PX (10x12mm) L1 Vishay IHLP2525EZER1R5M01 L4 Pulse PA2729.802NL T1 PA0801NL T3 PA3493NL
18 to 72 VIN
VCC
RS-
PGND
PGNDP
PGND
AS
VIN
SGNDP
PGND
SGND
FG
RS-
VCC
PGNDP
SGND
FG
PGND
VAUX
SGNDP
PGNDP VPK
+VOUT
RS+
PGNDP
VPK +VOUT
VA
RS+
SGND
VCC
VIN
PGND
RS-
PGND
VAUX
VA
PGND
PGND
SGNDPSGNDP SGNDP
PG
PG
+VOUT
AS
R5
68.1K 1206
R41 4.12K
R32
0
0402
E2
C27 10uF
1206
16V
R29
19.1K
C13
1.0uF 100V 1210
C31 1nF
R44 56.2K
R1
51.1 1206
R21 0
0402
R15 OPT 0603
R46
60.4K R47
15.0K
R40
0
R12 OPT
0402
C21 1uF 0805
C12 22uF 16V 1210
C23
1uF 0805
R33
0
0402
E1
C30 1nF
R10
0.004 2512
R24
100 0402
C37
1.0nF
T3
3
1 6
4
C28 10nF
C3 2.2uF 100V 1210
R20
100
Q5
IRF6217
4
15
2
36
7
8
C7
OPT
0805
C5 2.2uF 100V 1210
C35
0.1uF
R30
0
0402
C4 2.2uF 100V 1210
D6
OPT C34
OPT
1206
C17
0.1uF
R52
22K
C36
OPT
0402
R23
100 0402
R53
8.25K
R19 100
R43
OPT
0402
J2
-VIN
L5
OPT
C32
47pF
R13
OPT
0402
R49 1.87K
R54
0
0402
C18
470pF
R45
0 0402
Q1 FDMS86201
4
5
2 3 6 7 8
1
R36
11.5K
R38 100
E4
+
C8
68uF
16V
Q2 OPT
4
5
2 3 6 7 8
1
LTC3765EMSE
U1
14
3
2
15 16
12
4
6 7
17
8
10
13
1
9
11 5
NDRV
VCC
PG
IN+
IN-
RUN
AG
DELAY IS-
GND
IS+
FS/UV
SSFLT
PGND
GND2
GAMSIEROCR
C10
1nF
630V
1206
E3
D3 ZHCS400
Q8 OPT
R7
909
0805 D1
ES1PD
Q4
FDMS86200
4
5
23
678
1
C16
1nF
C2 2.2uF 100V 1210
T1
7 2
3
11
4 5 6 1
R31
0
0402
R4
68.1K
1206
C15
OPT
50V
+
C9
68uF
16V
R18 100K
0805
+
C1 33uF
100V
C24
2.2nF 250V 1812
L1
1.5uH
R56
1.00K
C29 33nF
R27 0.75 0805
J1
+VIN
FMMT491A
Q7
R51 13.3K C33
2.2nF
C26
0ohms
C22 220pF
R26 OPT 0603
R37 909
0805
J4 -VOUT
Q6
FDC2512
3
4 1
2
5
6
R11 75
0805
LTC3766EGNU2
7
2
23
6
14
18
17
1
28
26
25
16
15
9
4
27
22
21
10
5
12 13
11
820
3
19
24
ITH
FG
SW
FB
GND
IS+
IS-
SG
VCC
PT+ PT-
REGSD
FS/SYNC
SS
MODE
PGND
VIN
NDRV
IPK
PHASE
VS+
VS-
VSOUT
RUN FGD/SWB
VSEC
SGD
VAUX
D4 ES1PD
R28
OPT
0402
R22
1.82K
1206
R39
100
R17
61.9K
0805
L4
8.0uH
2 1
Q3
FDMS86322
4
5
23
678
1
R9
0
0402
D5
ZHCS400
R48
4.99K
R14 0.006
2512
C6
47pF
200V 1206
C20
0.1uF
R25
10K
J3 +VOUT
C25
33nF
COG 0805
R35
1.82K
R42
OPT
C11 22uF 16V 1210
C14 0.1uF 1206
R50 604
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10
dc1739afb
DEMO MANUAL DC1739A-B
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2011
LT 0612 REV B • 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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