1
dc2456af
DEMO MANUAL DC2456A
Description
LTC3779
High Voltage, High Efficiency
48V/10A Synchronous Buck-Boost Converter
Demonstration circuit 2456A is a high voltage, high effi-
ciency synchronous buck-boost DC/DC converter with
a 16V to 120V input voltage range. It can supply a 10A
maximum load current with a 48V output. The demo
board features the LT C
®
3779EFE controller. The constant
frequency current mode architecture allows a phase-lock-
able frequency of up to 600kHz, while an optional output
current feedback loop provides support for applications
such as battery charging. With a wide input range, wide
output range and seamless transfers between operation
modes, the LTC3779 is ideal for Industrial, Automotive,
Medical, Military and Avionics applications.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Analog
Devices, Inc. All other trademarks are the property of their respective owners.
performance summary
The light load operation mode of the converter is deter-
mined with the MODE pin. Use JP2 jumper to select pulse-
skipping mode or forced continuous mode (CCM) opera-
tion. The switching frequency is pre-set at about 200kHz.
The converter can also be externally synchronized to an
external clock through the PLLIN pin (PLLIN terminal on
the board). To shut down the converter, force the RUN pin
below 1.2V (SW1: OFF). The power good output (PGOOD
terminal) is low when the output voltage is outside of the
±10% regulation window.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2456A
Specifications are at TA = 25°C
PARAMETER CONDITION VALUE
Input Voltage Range 16V to 120V
Output Voltage, VOUT VIN = 21V to 120V, IOUT = 0A to 10A 48V ±2%
Maximum Output Current, IOUT VIN = 21V to 120V, VOUT = 48V 10A
Default Operating Frequency 200kHz
Typical Efficiency 48VIN, 48VOUT, 10A 98.7%
36VIN, 48VOUT, 10A 99.0%
72VIN, 48VOUT, 10A 98.7%
Typical Output Ripple 48VIN, 48VOUT, 10A 480mV
2
dc2456af
DEMO MANUAL DC2456A
Quick start proceDure
Demonstration circuit 2456A is easy to set up to evaluate
the performance of the LTC3779. Refer to Figure1 for
the proper measurement equipment setup and follow the
procedure below:
1. With power off, connect the input power supply to VIN
(16V to 120V) and GND (input return).
2. Connect the 48V output load between VOUT and GND
(Initial load: no load).
3. Connect the DVMs to the input and the output.
4. Turn on the input power supply and then check for the
proper output voltages. VOUT should be 48V ±2%.
5. Once the proper output voltages are established,
adjust the loads within the operating range and
observe the output voltage regulation, ripple voltage
and other parameters.
Note: When measuring the output or input voltage rip-
ple, do not use the long ground lead on the oscilloscope
probe. See Figure2 for the proper scope probe technique.
Short, stiff leads need to be soldered to the (+) and (–)
terminals of an output capacitor. The probe’s ground ring
needs to touch the (–) lead and the probe tip needs to
touch the (+) lead.
Additional Note:
R2, R3, R4 and C10 is needed for additional/constant
output current limit only. If this average current loop func-
tion is not used, short R2 and remove R3, R4 and C10;
and then short IAVGSNSP and IAVGSNSN pins together,
and tie them to V5.
Output Current Derating
Demonstration circuit 2456A is designed to supply 48V
output with a 10A maximum load current. Figure3 shows
the full load efficiency and loss vs. the input voltage. For
thermal concern, hotspot temperature is limited below
90°C for input voltage range between 21V and 120V with
200LFM air flow. Figure4 and Figure5 show the thermal
performance of Demonstration circuit 2456A with 21VIN,
48VOUT, 10A load current and 120VIN, 48VOUT, 10A load
current, respectively. Further decreasing the input voltage
below 21V with 10A load current is not recommended.
For applications with input voltage range between 16V
and 21V, the output current derating curve is shown as
Figure6. For input voltage range between 36V and 72V
which is popular in Telecom Industry, Demonstration cir-
cuit 2456A can handle the 10A full load current without
any forced air flow. Figure7, Figure8 and Figure9 show
the thermal performance at 36VIN, 48VIN and 72VIN,
respectively.
Besides the thermal performance, another limit factor
for high output power capability is the saturation cur-
rent of the power inductor. To supply 48VOUT, 10A load
current with the input voltage below 21V, 15µH inductor
with P/N 60068 from Payton Planar Magnetics Ltd. is
recommended. Please contact the manufacture for detail
information. Figure10 shows the thermal performance at
18VIN, 48VOUT, 10A load current with 400LFM air flow.
For applications with input voltage range between 16V
and 18V, the output current derating curve is shown as
Figure6.
3
dc2456af
DEMO MANUAL DC2456A
Quick start proceDure
+
–
VIN
IIN
1mΩ
Shunt
+
–
VIN
16V to 120V
+–
+
–
VOUT
IOUT
1mΩ
Shunt
DC2456A F01
LOAD
+–
Figure1. Proper Measurement Equipment Setup
+ –
VOUT GND
COUT
Figure2. Measuring Output Voltage Ripple
4
dc2456af
DEMO MANUAL DC2456A
Figure3. Efficiency and Loss vs Input Voltage (IOUT = 10A)
LOAD CURRENT (A)
12
EFFICIENCY (%)
LOSS (W)
100
96.5
99.5
98.5
97.5
99.0
98.0
97.0
96.0
20.0
EFFICIENCY
LOSS
2.5
17.5
12.5
7.5
15.0
10.0
5.0
0
72 12048 96
DC2456A F03
13260 10836 8424
Figure4. DC2456A Thermal Performance at 21VIN, 48VOUT, 10A Load Current with
200LFM Air Flow
Quick start proceDure
5
dc2456af
DEMO MANUAL DC2456A
Figure5. DC2456A Thermal Performance at 120VIN, 48VOUT, 10A Load Current
with 200LFM Air Flow
INPUT VOLTAGE (V)
12
MAX LOAD CURRENT (A)
10.5
10.0
6.5
9.5
8.5
7.5
9.0
8.0
7.0
6.0 17 2115 19
DC2456A F06
2416 20 232214 1813
PAYTON 60068
WITH 400LFM AIR FLOW
WURTH 7443641500
WITH 200LFM AIR FLOW
Figure6. DC2456A Output Current Derating vs Input Voltage (∆TMAX = 65°C)
Quick start proceDure
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dc2456af
DEMO MANUAL DC2456A
Figure8. DC2456A Thermal Performance at 48VIN, 48VOUT, 10A Load Current
with No Forced Air Flow
Figure7. DC2456A Thermal Performance at 36VIN, 48VOUT, 10A Load Current
with No Forced Air Flow
Quick start proceDure
7
dc2456af
DEMO MANUAL DC2456A
Figure9. DC2456A Thermal Performance at 72VIN, 48VOUT, 10A Load Current
with No Forced Air Flow
Figure10. DC2456A Thermal Performance at 18VIN, 48VOUT, 10A Load Current
with 400LFM Air Flow
Quick start proceDure
8
dc2456af
DEMO MANUAL DC2456A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
1 1 CC1 CAP, 0603 100pF 10% 50V C0G AVX 06035A101KAT2A
2 1 CC2 CAP, 0603 10nF 10% 50V X7R AVX 06035C103KAT2A
3 0 CF1 CAP, 0603 OPTION OPTION
4 2 CIN1, CIN2 CAP, 10µF 20% 125V ELEC SUNCON 125HVH10M
5 2 COUT1, COUT2 CAP, 56µF 20% 63V HYB POLYMER UNITED CHEMI-CON HHXA630ARA560MJA0
6 2 C52, CSS CAP, 0603 0.1µF 10% 50V X7R AVX 06035C104KAT2A
7 2 C4, C22 CAP, 0603 0.22µF 20% 16V X7R AVX 0603YC224MAT2A
8 0 C7, C8, C12, C13, C57 CAP, 0805 OPTION OPTION
9 9 C9, C14, C25, C26, C27, C35, C36,
C37, C48
CAP, 2220 1µF 10% 250V X7R MURATA GRM55DR72E105KW01L
10 1 C10 CAP, 0603 4.7µF 10% 10V X5R MURATA GRM188R61A475KE15D
11 1 C11 CAP, 0603 220pF 5% 100V C0G MURATA GRM1885C2A221JA01D
12 6 C15, C40, C42, C43, C44, C45 CAP, 0805 0.1µF 10% 250V X7T TDK CGA4J3X7T2E104K125AE
13 12 C16, C17, C19, C20, C21, C23, C28,
C29, C30, C31, C32, C53
CAP, 1210 3.3µF 10% 50V X7R AVX 12105C335K4T2A
14 1 C18 CAP, 1206 10µF 20% 6.3V X5R AVX 12066D106MAT2A
15 1 C24 CAP, 0805 1µF 10% 50V X7R AVX 08055C105KAT2A
16 0 C41, C46, C47, C54, C55 CAP, 0805 0.1µF 10% 250V X7T OPTION TDK CGA4J3X7T2E104K125AE OPTION
17 1 C49 CAP, 0603 47nF 10% 50V X7R MURATA GRM188R71H473KA61D
18 2 C50, C51 CAP, 1210 22µF 20% 16V X5R AVX 1210YD226MAT2A
19 1 C56 CAP, 0603 1F 10% 50V X5R TDK C1608X5R1H105K080AB
20 0 C58 CAP, 1210 OPTION OPTION
21 2 D4, D7 DIODE, SCHOTTKY 1A 200V POWERDI123 DIODES INC. DFLS1200-7
22 1 D8 DIODE, ZENER 5.1V 350mW SOT23-3 DIODES INV. BZX84C5V1-7-F
23 0 D9 DIODE, OPTION DIODES INC. BAS16-7-F OPTION
24 0 D10 DIODE, SCHOTTKY OPTION SMB OPTION
25 0 D11 DIODE, SCHOTTKY OPTION SMA OPTION
26 0 D12, D13 DIODE, SCHOTTKY OPTION POWERDI5 OPTION
27 4 E1, E2, E3, E7 TURRET MILL-MAX 2308-2-00-80-00-00-07-0
28 7 E4, E5, E6, E8, E9, E10, E11 TURRET MILL-MAX 2501-2-00-80-00-00-07-0
29 1 JP2 HEADER, 3PIN 2mm SAMTEC TMM-103-02-L-S
30 4 J1, J2, J3, J4 JACK, BANANA KEYSTONE 575-4
31 1 L1 IND, 15µH WURTH 7443641500
32 0 L2 IND, OPTION OPTION
33 1 L3 IND, 220µH SUMIDA CDRH105RNP-221NC
34 4 MH1, MH2, MH3, MH4 STANDOFF, SNAP ON 9.525mm KEYSTONE 8834
35 0 Q1, Q7, Q8 XSTR, OPTION OPTION
36 2 Q2, Q6 XSTR, N-CHANNEL POWER MOSFET INFINEON BSC110N15NS5
37 1 Q3 XSTR, N-CHANNEL POWER MOSFET INFINEON BSC028N06NS
38 1 Q4 XSTR, N-CHANNEL POWER MOSFET INFINEON BSC093N15NS5
39 2 Q5, Q9 XSTR, N-CHANNEL POWER MOSFET INFINEON BSC066N06NS
9
dc2456af
DEMO MANUAL DC2456A
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
40 0 Q11, Q12, Q13, Q14, Q15, Q16,
Q17, Q18, Q19, Q20, Q21, Q22,
Q23, Q24, Q25, Q26
AUTOMOTIVE MOSFET OPTION OPTION
41 0 Q10 XSTR, OPTION TO-252 OPTION
42 1 RC RES, 0603 10kΩ 5% 0.1W VISHAY CRCW060310K0JNEA
43 1 RFB1 RES, 0805 475kΩ 1% 0.125W VISHAY CRCW0805475KFKEA
44 2 RFB2, R45 RES, 0603 12.1kΩ 1% 0.1W VISHAY CRCW060312K1FKEA
45 10 R1, R11, R15, R17, R23, R27, R35,
R36, R41, R48
RES, 0Ω JUMPER VISHAY CRCW06030000Z0EA
46 1 R2 RES, 2512 0.004Ω 1% 1W PANASONIC ERJ-M1WSF4M0U
47 4 R3, R4, R9, R10 RES, 0603 100Ω 1% 0.1W VISHAY CRCW0603100RFKEA
48 1 R5 RE, 0805 5.1Ω 5% 0.125W VISHAY CRCW08055R10JNEA
49 0 R6, R12, R16, R34, R40 RES, 0603 OPTION OPTION
50 1 R7 RES, 0603 100kΩ 1% 0.1W VISHAY CRCW0603100KFKEA
51 2 R8, R39 RES, 0603 10Ω 5% 0.1W VISHAY CRCW060310R0JNEA
52 2 R13, R14 RES, 0603 1kΩ 1% 0.1W VISHAY CRCW06031K00FKEA
53 2 R18, R19 RES, 2512 0.008Ω 1% 2W BOURNS CRE2512-FZ-R008E-2
54 1 R20 RES, 2512 0Ω JUMPER TEPRO RN5326
55 1 R21 RES, 0603 56.2kΩ 1% 0.1W VISHAY CRCW060356K2FKEA
56 1 R22 RES, 0805 124kΩ 1% 0.125W VISHAY CRCW0805124KFKEA
57 1 R25 RES, 0603 1.21kΩ 1% 0.1W VISHAY CRCW06031K21FKEA
58 0 R28, R29, R32, R42 RES, 0805 OPTION OPTION
59 1 R30 RES, 0805 41.2kΩ 1% 0.125W VISHAY CRCW080541K2FKEA
60 1 R31 RES, 0805 3kΩ 1% 0.125W VISHAY CRCW08053K00FKEA
61 0 R37, R38 RES, 2512 0.01Ω 1% 1W OPTION VISHAY WSL2512R0100FEA OPTION
62 1 R43 RES, 0805 0Ω JUMPER VISHAY CRCW08050000Z0EA
63 1 R44 RES, 0805 150kΩ 1% 0.125W VISHAY CRCW0805150KFKEA
64 1 R46 RES, 0603 113kΩ 1% 0.1W VISHAY CRCW0603113KFKEA
65 1 R47 RES, 0603 8.06kΩ 1% 0.1W VISHAY CRCW06038K06FKEA
66 1 R49 RES, 1206 0Ω JUMPER VISHAY CRCW12060000Z0EA
67 0 R50 RES, 1206 OPT OPTION
68 1 SW1 SWITCH, SUB-MINIATURE SLIDE 300mA
6V
C&K JS202011CQN
69 1 U1 IC, BUCK-BOOST CONVERTER LINEAR TECH. LTC3779EFE38
70 1 U2 IC, SYNCHRONOUS STEP-DOWN
REGULATOR
LINEAR TECH. LTC3639EMSE
71 1 XJP2 SHUNT 2mm SAMTEC 2SN-BK-G
parts List
10
dc2456af
DEMO MANUAL DC2456A
schematic Diagram
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B B
A A
1. ALL RESISTORS AND CAPACITORS ARE 0603.
NOTE: UNLESS OTHERWISE SPECIFIED,
WURTH 7443641500
25V 2512
VOS+
VOS+
VOUT
VIN+
VOUT
V5
VIN+
VIN+
VOUT1
V5
VIN+
V5
V5
DRVCC
DRVCC
EXTVCC
EXTVCC
DRVCC
VOUT
VIN+
VBIAS
V5
VIN+
TG1
SW1
BG1
TG2
SW2
BG2
CS
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
12
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
12
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
12
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
]A jA
PROD
-4 07/13/17
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
]A jA
PROD
-4 07/13/17
REVISION HISTORY
DESCRIPTION DATE APPROVEDECO REV
]A jA
PROD
-4 07/13/17
R11 0
E7
GND
R17 0
C4
0.22uF
25V
Q2
5
2
4
1
3
C10
4.7uF
R27 0
J4
GND
R16
OPT
R29
OPT
0805
C22
0.22uF
25V
R41 0
E5
SS
C29
C44
0.1uF
250V
0805 C17
3.3uF
100V
D11
OPT
Q7
OPT
5
2
4
1
3
CC2
10nF
R15 0
E8
PLLIN
R5
5.1
0805
R9 100
R25
1.21K
1%
R19
0.008
2W
2512
R14 1k
R10 100
R8
10
C23
3.3uF
100V
1210
C58
OPT
1210
C13
OPT
0805
RC
10K
R6 OPT
R28
OPT
0805
J1 VIN
16V - 120V
R1 0
Q3
BSC028N06NS
5
2
4
1
3
C18 10uF
1206
CSS
0.1uF
R40 OPT
R34 OPT
C36
D7
DFLS1200-7
Q6
BSC110N15NS5
5
2
4
1
3
U1
LTC3779EFE38
TG2
21
BOOST2
22
RUN
24
IAVGSNSP
26
IAVGSNSN
28
VOUTSNS
30
VINSNS
32
VIN
34
BOOST1
36
TG1
37
BG1
1
VINOV
2
DRVSET
3
SGND
4
EXTVCC
5
NDRV
6
DRVCC
7
V5
8
SS
9
VFB
10
SW2
20
SENSEP
11
SENSEN
12
ITH
13
SGND
14
MODE
15
PLLIN
16
FREQ
17
PGOOD
18
BG2
19
SW1
38
PGND
39
D9 OPT
C43
C7
OPT
0805
C55
C47
C31
+
COUT1
56uF
63V
C35
1uF
2220
250V
C46
0805
OPT
250V
C11
220pF
+
CIN1
10uF
125V
C19
C37
C57
OPT
0805
R7
100k
1%
D8
BZX84C5V1
RFB2
12.1K 1%
E4
PGOOD
J2 GND
R32 OPT
0805
C27
R2 0.004
1W
E3
VIN+
R18
0.008
2W
2512
+
CIN2
10uF
125V
L1
15uH
R12 OPT
Q5
BSC066N06NS
5
2
4
1
3
C16
C26
C32 C40
0.1uF
250V
0805
R50 OPT
1206
Q8
OPT
5
2
4
1
3
C20
C53
R23 0
D10
OPT
SW1
JS202011CQN
RUN
ON
OFF
4 1
5 2
6 3
R21 56.2k
200kHz
Q10
OPT
32
1
R30
41.2K
1%
0805
C12
OPT
0805
C14
R3 100
C54
0805
OPT
250V
E2
VOS+
C28
1210
C9
1uF
250V
C8
OPT
0805
CC1
100pF
R39
10
C42
0.1uF
250V
0805
R22
124K 1%
0805
C15
0.1uF
250V
0805
C45
E10
EXTVCC
Q4
BSC093N15NS5
5
2
4
1
3
JP2
PULSE SKIP
CCM
MODE
1
3
2
C41
0805
OPT
250V
E9
SGND
C21
Q1
OPT
5
2
4
1
3
E6
ITH
C25
2220
R20 0
R48
0
E11
RUN
R13 1k C30
R49 0
1206
R36
0
+
COUT2
56uF
63V
Q9 BSC066N06NS
5
2
4
1
3
J3
VOUT
48V AT 10A MAX
RFB1
475K
1%
0805
C24
1uF
0805
C56
1uF
25V
R4 100
E1 VOS-
R35
0
R31
3K
0805
1%
OPT
CF1
D4
DFLS1200-7
TG2
CS
RUN
IINSENSEP
IINSENSEN
BG1
TG1
SW1
SW2
BG2
IINSENSEN
IINSENSEP
RUN
11
dc2456af
DEMO MANUAL DC2456A
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
5
5
4
4
3
3
2
2
1
1
D D
C C
B B
A A
CDRH105R
12V / 100mA
OPTIONAL DPAK/D2PAK
MOSFETS FOR AUTOMOTIVE
APPLICATION
VIN+ VIN+
VOUT1 VOUT1
VIN+ VIN+
VOUT1 VOUT1
VBIAS
VOUTVIN+
VOUT1
TG1
BG2
SW1
SW2
BG1
TG2
CS
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
22
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
22
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
SIZE
DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: (408)434-0507
Milpitas, CA 95035
Phone: (408)432-1900
1630 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
4
Thursday, July 20, 2017
22
HIGH EFFICIENCY HIGH VOLTAGE
N/A LTC3779EFE38
DEMO CIRCUIT 2456A
]A jA
`A \A
BUCK-BOOST CONVERTER
Q17
OPT
32
1
OPT
L2
D12
OPT
Q11
OPT
32
1
Q20
OPT
32
1
C49
47nF
Q22
OPT
23
1
D13
OPT
Q12
OPT
32
1
Q23
OPT
32
1
C50
22uF
25V
1210
Q25
OPT
32
1
C52
0.1uF
Q16
OPT
23
1
R38
OPT
1W
2512
C51
22uF
25V
1210
R47
8.06k
1%
R37
OPT
1W
2512
U2
LTC3639EMSE
SW
1
VIN
3
FBO
5
VPRG1
7
VPRG2
6
GND
8
VFB
9
SS
10
ISET
11
OVLO
12
RUN
14
GND
16
GND
17
C48
1uF
2220
250V
Q18
OPT
23
1
Q19
OPT
23
1
Q21
OPT
32
1
Q13
OPT
23
1
L3
220uH
R43
0
0805
Q15
OPT
32
1
R46
113k
1%
Q24
OPT
23
1
R44
150k
1%
0805
R42
OPT
0805
R45
12.1K
1%
Q14
OPT
23
1
Q26
OPT
23
1
12
dc2456af
DEMO MANUAL DC2456A
LINEAR TECHNOLOGY CORPORATION 2017
LT 0917 • 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 application
engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation