Linear ANALOG DEVICES DC2543B Quick setup guide

1
DEMO MANUAL DC2543B
Rev. 0
DESCRIPTION
LTC7820EUFD
High Efficiency, Charge Pump
DC/DC Converter
Demonstration circuit 2543B is a high efficiency, high
density, open loop charge pump (inductorless) DC/DC
converter. This demo board is a voltage divider which
achieves a 2:1 step-down ratio from an input voltage from
36V to 60V. The output voltage is a fixed ratio of half of the
input voltage (VIN/2) and can supply a 10A load current.
This demo board has the option to deliver a 20A maximum
load with the addition of 15 chip capacitors. See Figure8
and Figure10 for the details.
The DC2543B provides a very high efficiency solution of
98.7% when converting 48VIN to 24VOUT at 10A as shown
in Figure3. When configured for a 20A output, an effi-
ciency of up to 98.4% is achievable for a 48VIN to 24VOUT
at 20A as shown in Figure8.
The demo board features the LT C
®
7820, a fixed ratio high
voltage high power switched capacitor/charge pump
controller in a 4mm × 5mm QFN package. Please see
LTC7820 data sheet for more detailed information.
PERFORMANCE SUMMARY
The DC2543B needs to be powered on with no load cur-
rent or a very small load current (less than 50mA) with
the default setup. Large load current can be applied after
VOis established. The board offers a disconnect FET
option which is controlled by the LTC7820 FAULT pin
to disconnect the load during startup as shown in the
schematic. Please refer to “Voltage Divider Prebalance
Before Switching”section in the LTC7820 data sheet for
more details regarding the startup of the voltage divider.
The board also features some protection functions
such as overcurrent and thermal shutdown to make it a
reliablesolution.
Design files for this circuit board are available.
Specifications are at TA= 25°C
PARAMETER CONDITION VALUE
Input Voltage Range 36V to 60V
Output Voltage, VOUT VIN = 36 to 60V, IOUT = 0A to 10A VIN/2
Maximum Output Current, IOUT VIN = 36 to 60V, VOUT = VIN/2 10A
Typical Efficiency VIN = 48V, VOUT = 24V, IOUT = 10A 98.7%
Peak Efficiency VIN = 48V, VOUT = 24V 99%
Switching Frequency 200kHz
All registered trademarks and trademarks are the property of their respective owners.
NOTE: DC2543B demo board includes a Schottky diode added across the output. This manual describes the demo
board entitled “Demo Circuit 2543B.” The DC2543B replaces the DC2543A.
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2
DEMO MANUAL DC2543B
Rev. 0
QUICK START PROCEDURE
Demonstration circuit 2543B is easy to set up to evaluate
the performance of the LTC7820. 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
(36V to 60V) and GND (input return).
2. Connect the output loads between VOUT and GND
(Initial load: no load). Refer to Figure1.
3. Connect the DVMs to the input and output.
4. Check the default jumper/switch position:SW1 (RUN):
OFF; JP2 (BIAS): ON.
5. Turn on the input power supply and adjust voltage
to48V.
NOTE:Make sure that the input voltage does not
exceed60V.
6. Turn on the switches: SW1: ON.
7. Check for the proper output voltages from VO_SNS+to
VO_SNS–.
8. Once the proper output voltage is established, adjust
the loads within the operating range and measure the
efficiency, output ripple voltage and other parameters.
9. After completing all tests, adjust the load to 0A, power
off the input power supply.
Notes:
1. When measuring the output or input voltage ripple,
do not use the long ground lead on the oscilloscope
probe. See Figure3 for the proper scope probe tech-
nique. 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.
2. When doing the load step test with the on-board
dynamic load circuit, please make sure the load step-
up pulse duty cycle does not exceed 2% and the pulse
duration is less than 500µs so that the temperature
of the MOSFETs Q9, Q23 in the dynamic load circuit
stay in the safe region. Instead of using the on-board
dynamic load circuit, an electric load can also be used
for the load step test, which does not have the 2%
maximum duty cycle limit for the load step.
3. It is recommended to set the electronic load in CR (con-
stant resistance) mode for evaluation of the DC2543B
board. Some electronic loads draw negative current in
CC (constant current) mode when evaluating the output
overcurrent protection feature of DC2543B, which can
violate the absolute maximum voltage rating –0.3V for
VLOW pin.
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3
DEMO MANUAL DC2543B
Rev. 0
QUICK START PROCEDURE
–
+–
+
+
VIN
36V to 60V
–
+
–
+
–
LOAD
DC2543B F01
+ –
VOUT GND
COUT
Figure1. Proper Measurement Equipment Setup
Figure2. Measuring Output Voltage Ripple
Note: It is recommended to set the electronic load in CR (constant resistance) mode for evaluation of
the DC2543B board. Some electronic loads draw negative current in CC (constant current) mode when
evaluating the output overcurrent protection feature of DC2543B, which can violate the absolute maximum
voltage rating –0.3V for VLOW pin.
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4
DEMO MANUAL DC2543B
Rev. 0
QUICK START PROCEDURE
Figure3. Efficiency vs Load Current at VIN = 48V,
VOUT = 24V, fSW = 200kHz
OUTPUT LOAD CURRENT (A)
0
90
EFFICIENCY (%)
92
94
100
98
96
24 6 8 10
DC2543B F03
OUTPUT LOAD CURRENT (A)
0
23.0
23.2
23.4
23.6
VOUT (V)
23.8
24.0
24.6
24.4
24.2
24 6 8 10
DC2543B F04
Figure4. Load Regulation for 10A Design
at VIN = 48V, VOUT = 24V, fSW = 200kHz
Figure5. Output Voltage Ripple at VIN = 48V,
VOUT = 24V, IOUT = 10A, fSW = 200kHz
Figure6. Load Step at VIN = 48V, VOUT = 24V
2µs/DIV
VOUT
RIPPLE
20MHz BW
500mV/DIV
DC2543B F05
100µs/DIV
0A-5A-0A
LOAD STEP
VOUT
20MHz BW
500mV/DIV
DC2543B F06
Figure7. Thermal performance VIN = 48V, VOUT = 24V, IOUT = 10A,
TA= 23°C, No Airflow
Q1 Q3
Q6 Q7
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5
DEMO MANUAL DC2543B
Rev. 0
QUICK START PROCEDURE
OUTPUT LOAD CURRENT (A)
0
92
EFFICIENCY (%)
93
94
100
98
96
95
99
97
26 10 14 48 12 16 18 20
DC2543B F08
OUTPUT LOAD CURRENT (A)
0
23.0
VOUT (V)
23.2
23.4
24.6
24.2
23.8
23.6
24.4
24.0
26 10 14 48 12 16 18 20
DC2543B F09
Figure8. Efficiency vs Load Current at VIN = 48V,
VOUT = 24V, fSW = 200kHz*
Figure9. Load Regulation for 20A Design
at VIN = 48V, VOUT = 24V, fSW = 200kHz*
Figure10. Thermal performance at VIN = 48V, VOUT = 24V, IOUT = 20A
TA= 23°C, No Airflow*
* Note:Additional C11, C12, C60, C61, C22-C25, C69-C72, C30, C31, and C36 (10µF/50V, MURATA GRM32ER71H106KA12L) are populated;
RS1 is changed to 2.5mΩ (WSL20102L500FEB18) for this test.
Q1
Q3
Q6
Q7
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6
DEMO MANUAL DC2543B
Rev. 0
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP, 33µF 20% 80V ELEC PANASONIC EEHZA1K330P
2 8 C2, C3, C47, C49, C56, C57, C58, C59 CAP, 1210 2.2µF 10% 100V X7R MURATA GRM32DR72A225KA12
3 4 C4, C5, C15, C126 CAP, 0603 0.1µF 10% 100V X7R MURATA GRM188R72A104KA35D
4 2 C6, C7 CAP, 0805 4.7µF 10% 16V X7R MURATA GRM21BR71C475KA73K
5 1 C8 CAP, 0603 0.22µF 10% 25V X7R MURATA GRM188R71E224KA88D
6 2 C9, C26 CAP, 0603 0.47µF 10% 25V X7R MURATA GRM188R71E474KA12D
7 2 C17, C28 CAP, 0805 2.2µF 10% 50V X7R TDK C2012X7R1H225K125AC
8 11 C18, C19, C20, C21, C29, C66, C67 CAP, 1210 10µF 10% 50V X7R MURATA GRM32ER71H106KA12L
9 C68, C73, C74, C65
10 2 C27, C50 CAP, 0603 1µF 10% 50V X5R MURATA GRM188R61H105K
11 2 C52, C53 CAP, 1210 22µF 10% 25V X5R AVX 12103D226KAT2A
12 1 C54 CAP, 0603 47nF 10% 25V X7R AVX 06033C473KAT2A
13 1 C55 CAP, 0603 470pF 10% 50V X7R MURATA GRM188R71H471KA01D
14 3 D1, D2, D3 DIODE, SCHOTTKY CENTRAL SEMI. CMDSH-4E TR
15 1 D6* DIODE, SCHOTTKY ON SEMI, NRVTSAF5100E
16 2 D9, D10 DIODE, ZENER CENTRAL SEMI. CMHZ5236B TR
17 1 L2 IND, 68µH COILCRAFT., LPS6225-683MRB
18 1 Q1 XSTR, N-CHANNEL MOSFET INFINEON BSC027N06LS5
19 3 Q3, Q6, Q7 XSTR, N-CHANNEL MOSFET INFINEON BSC032N04LS
20 4 Q9, Q10, Q11, Q23 XSTR, N-CH 40V 14A TO-252 VISHAY SUD50N04-8M8P-4GE3
21 1 Q22 TRANSISTOR., SOT-23 FAIRCHILD., BSS123L
22 1 RS1 RES., CHIP, 0.005, 1%, 2010 VISHAY, WSL20105L000FEA
23 1 RS2 RES, 2010 0Ω JUMPER VISHAY WSL201000000ZEA9
24 2 R1, R7 RES, 0603 1kΩ 1% VISHAY CRCW06031K00FKEA
25 1 R2 RES, 0603 2.2Ω 5% YAGEO RC0603JR-072R2L
26 4 R5, R10, R24, R32 RES, 0603 0Ω JUMPER VISHAY CRCW06030000Z0EA
27 4 R9, R13, R17, R28 RES, 0603 10kΩ 1% NIC NRC06F1002TRF
28 1 R16 RES, 0603 60.4kΩ 1% VISHAY CRCW060360K4FKEA
29 1 R18 RES, 0603 100kΩ 1% VISHAY CRCW0603100KFKEA
30 1 R26 RES, 0603 154kΩ 1% YAGEO RC0603FR-07154KL
31 1 R27 RES, 0603 20kΩ 5% VISHAY CRCW060320K0JNEA
32 1 R29 RES, 0603 80.6kΩ 1% YAGEO RC0603FR-0780K6L
33 1 R30 RES. 2010 1Ω 1% 1W IRC LRC-LR2010-01-1R00-F
34 1 R31 RES, 0603 100Ω 5% VISHAY CRCW0603100R0JNEA
35 1 U1 IC, LTC7820EUFD, QFN 4mm × 5mm ANALOG DEVICES, LTC7820EUFD#PBF
36 1 U2 IC, LTC3630AEMSE ANALOG DEVICES, LTC3630EMSE#PBF
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7
DEMO MANUAL DC2543B
Rev. 0
PARTS LIST
Additional Demo Board Circuit Components
1 0 C10-C14, C16, C33, C34, C35, C36,
C60-C64, C51, C77
CAPACITOR, OPT
2 0 C30-C32, C22-C25, C69-C72, C127
3 0 Q2, Q4, Q5,Q8 OPT MOSFET, OPT
4 0 R6, R19, R2, R36, R8, R11, R12,
R20, R34, R35, R60
RESISTOR, OPT
Hardware: For Demo Board Only
1 9 E1, E2, E6-E8, E10, E12, E14, E15 TURRET MILL-MAX 2501-2-00-80-00-00-07-0
2 1 JP2 HEADER, 3 PIN 2mm WURTH ELEKTRONIK 62000311121
3 4 J1, J2, J3, J4 JACK, BANANA KEYSTONE, 575-4
4 2 J5, J6 CONN, BNC, 5 PINS CONNEX, 112404
5 1 SW1 SWITCH, SUBMINIATURE SLIDE C&K COMPONENTS, JS202011CQN
6 1 XJP2 SHUNT 2mm WURTH ELEKTRONIK 60800213421
7 4 STANDOFF STANDOFF, SNAP ON KEYSTONE 8833
*Note: D6 is for negative voltage clamping on VOUT of DC2543B board in output overcurrent test with electronic load. Some electronic loads draw negative
current in CC mode when evaluating the output overcurrent protection feature of DC2543B, which can violate the absolute maximum voltage rating –0.3V
for VLOW pin without D6 populated.
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8
DEMO MANUAL DC2543B
Rev. 0
SCHEMATIC DIAGRAM
5 5
4 4
3 3
2
2
1
1
D D C C
BB
A A
1/2VIN, 10A
NOTES: UNLESS OTHERWISE SPECIFIED,
1. CAPACITORS AND RESISTORS ARE 0603.
36V-60V
ON
RUN
OFF
G1
SW1
SW3 G4
MID
G3
G2
VIN1
VIN1
INTVCC
VOUT1
VIN1VIN
INTVCC EXTVCC
VIN1 VIN1 VIN VOUT1
INTVCC
INTVCC
INTVCC
VIN
VOUT VIN
VIN1 VIN
VIN1
VOUT
VOUT
FAULTB
BOOST2
FAULTB
BOOST2
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 1 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 1 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 1 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
JL
PRODUCTION 71-92-32
__
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
JL
PRODUCTION 71-92-32
__
REVISION HISTORY
DESCRIPTION DATE
APPROVED
ECO REV
JL
PRODUCTION 71-92-32
__
C15 0.1uF
100V
J4 GND
C64
OPT
U1
LTC7820EUFD
NC
2
RUN
6
FAULT
9
PGOOD
7
TIMER
4
UV
8
ISENSE+27
EXTVCC
11
ISENSE-28
G4 15
INTVCC
12
SW3 16
G3 17
G2 21
HYS_PRGM
3
FREQ
5
BOOST3 18 BOOST2 22
VLOW 20
VLOW_SENSE 19
VHIGH_SENSE 1
Vcc14
SW1 25
G1 24
BOOST1 23
GND
29
NC
10
NC
13
NC
26
Q4
OPT
4
5
6
7
8
3
1
2
SW1
1
2
3
4
5
6
C23 C66
Q22
BSS123L
2 3
1
C36 OPT 1210
50V
D3 CMDSH-4
21
C6
4.7uF
16V
0805
C71
+C127
OPT 100V
C28
2.2uF 0805
50V
R10 0
Q1
BSC027N06LS5
4
5
6
7
8
3
1
2
R1
1k 1%
D6 NRVTSAF5100
C31
R36
OPT
0805
C19
R20
OPT
1%
R18
100K
1%
E1
VIN
RS1 0.005
2010
Q8
OPT
4
5
6
7
8
3
1
2
C16
OPT
D10
CMHZ5236B
R5
0
C67
10uF 1210
C2 2.2uF 1210 100V
C59 2.2uF 1210 100V
C24
R31
100
E6
RUN
C73 10uF
1210
50V
C72
Q7
BSC032N04LS
4
5
6
7
8
3
1
2
E12
VO_SNS-
C14 1210
C4
0.1uF
100V
R60 OPT
R17 10K
1%
C34
R8
OPT
1%
D9
CMHZ5236B
C8 0.22uF
R11
OPT
Q2
OPT
4
5
6
7
8
3
1
2
C68
J3 VOUT
C10 OPT
0805
R32
0
R7 1k 1%
C60 OPT 1210
D2
CMDSH-4
2 1
C20
50V
C32
C7
4.7uF
25V 0805
E2
GND
Q6
BSC032N04LS
4
5
6
7
8
3
1
2
R9 10K
1%
R21
OPT
0805
C13
Q11
SUD50N04
1
2
3
C56 2.2uF 1210 100V
RS2 0
2010
R35 OPT
Q3
BSC032N04LS
4
5
6
7
8
3
1
2
C17
2.2uF 0805
50V
C61
C12
C74 10uF
1210
50V
R2
2.2
C11 OPT
R13 10K
1%
R19
OPT
0805
R12
OPT
C25
C35
E10
VO_SNS+
D1
CMDSH-4
2 1
C26 0.47uF
C69
OPT 1210 50V
+
C1
33uF
80V
C126
0.1uF
C29 10uF 1210 50V
R34
OPT
J2
GND
C62
C3 2.2uF 1210 100V
C18
R6
OPT
0805
C5
0.1uF
100V
C22
OPT 1210 50V
C65
50V
C27 1uF
C33
Q5
OPT
4
5
6
7
8
3
1
2
Q10
SUD50N04
1
23
R16
60.4K
1%
E7
FAULTB
C57 2.2uF 1210 100V
C70
C9
0.47uF
C58 2.2uF 1210 100V
E8
PGOOD
J1
VIN
C77 OPT
C63
C30 OPT
C21
10uF 1210
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9
DEMO MANUAL DC2543B
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog
Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications
subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
SCHEMATIC DIAGRAM
5 5
4
4
3
3
2
2
1
1
D D CC B B A A
2% DUTY CYCLE MAX.
DO NOT EXCEED
DYNAMIC LOAD CIRCUIT
7V BIAS
VOUT
VIN EXTVCC
+7V
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 2 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 2 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
SIZE DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
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
1
Monday, March 26, 2018 2 2
HIGH EFFICIENCY,CHARGE PUMP DC/DC CONVERTER
HZ
JL
N/A LTC7820EUFD
DEMO CIRCUIT 2543B
R30 1 1% 2010
Q23
SUD50N04
1
23
R27 20K
R29 80.6k 1%
C52
22uF 25V
1210
U2
LTC3630AEMSE
SW 1
VIN
3
FBO
12
VPRG1 7
VPRG2 6
GND
8
VFB 9
SS 10
ISET
11
GND
14
RUN
5
GND
16
GND
17
E15
GND
L2
68uH
LPS6225-683MRB
R28
10k
1%
C49 2.2uF 1210 100V
C53
22uF 25V
1210
C55 470pF
R24 0
VOUT
J5
C54
47nF
C50 1uF
C47 2.2uF 1210 100V
JP2
ON
OFF
BIAS
1
3
2
IOSTEP
J6
E14
IO_CLK
R26
154K
1%
C51 OPT
Q9
SUD50N04
1
23
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10
DEMO MANUAL DC2543B
Rev. 0
 ANALOG DEVICES, INC. 2018
DC2543B 1018(0)
www.analog.com
ESD Caution
ESD (electrostatic discharge) sensitive device. Charged devices and circuit boards can discharge without detection. Although this product features patented or proprietary protection
circuitry, damage may occur on devices subjected to high energy ESD. Therefore, proper ESD precautions should be taken to avoid performance degradation or loss of functionality.
Legal Terms and Conditions
By using the evaluation board discussed herein (together with any tools, components documentation or support materials, the “Evaluation Board”), you are agreeing to be bound by the terms and
conditions set forth below (“Agreement”) unless you have purchased the Evaluation Board, in which case the Analog Devices Standard Terms and Conditions of Sale shall govern. Do not use the Evaluation
Board until you have read and agreed to the Agreement. Your use of the Evaluation Board shall signify your acceptance of the Agreement. This Agreement is made by and between you (“Customer”)
and Analog Devices, Inc. (“ADI”), with its principal place of business at One Technology Way, Norwood, MA 02062, USA. Subject to the terms and conditions of the Agreement, ADI hereby grants to
Customer a free, limited, personal, temporary, non-exclusive, non-sublicensable, non-transferable license to use the Evaluation Board FOR EVALUATION PURPOSES ONLY. Customer understands and
agrees that the Evaluation Board is provided for the sole and exclusive purpose referenced above, and agrees not to use the Evaluation Board for any other purpose. Furthermore, the license granted
is expressly made subject to the following additional limitations:Customer shall not (i) rent, lease, display, sell, transfer, assign, sublicense, or distribute the Evaluation Board;and (ii) permit any Third
Party to access the Evaluation Board. As used herein, the term “Third Party”includes any entity other than ADI, Customer, their employees, affiliates and in-house consultants. The Evaluation Board is
NOT sold to Customer;all rights not expressly granted herein, including ownership of the Evaluation Board, are reserved by ADI. CONFIDENTIALITY. This Agreement and the Evaluation Board shall all
be considered the confidential and proprietary information of ADI. Customer may not disclose or transfer any portion of the Evaluation Board to any other party for any reason. Upon discontinuation of
use of the Evaluation Board or termination of this Agreement, Customer agrees to promptly return the Evaluation Board to ADI. ADDITIONAL RESTRICTIONS. Customer may not disassemble, decompile
or reverse engineer chips on the Evaluation Board. Customer shall inform ADI of any occurred damages or any modifications or alterations it makes to the Evaluation Board, including but not limited
to soldering or any other activity that affects the material content of the Evaluation Board. Modifications to the Evaluation Board must comply with applicable law, including but not limited to the RoHS
Directive. TERMINATION. ADI may terminate this Agreement at any time upon giving written notice to Customer. Customer agrees to return to ADI the Evaluation Board at that time. LIMITATION OF
LIABILITY. THE EVALUATION BOARD PROVIDED HEREUNDER IS PROVIDED “AS IS”AND ADI MAKES NO WARRANTIES OR REPRESENTATIONS OF ANY KIND WITH RESPECT TO IT. ADI SPECIFICALLY
DISCLAIMS ANY REPRESENTATIONS, ENDORSEMENTS, GUARANTEES, OR WARRANTIES, EXPRESS OR IMPLIED, RELATED TO THE EVALUATION BOARD INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTY OF MERCHANTABILITY, TITLE, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS. IN NO EVENT WILL ADI AND ITS
LICENSORS BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES RESULTING FROM CUSTOMER’S POSSESSION OR USE OF THE EVALUATION BOARD, INCLUDING
BUT NOT LIMITED TO LOST PROFITS, DELAY COSTS, LABOR COSTS OR LOSS OF GOODWILL. ADI’S TOTAL LIABILITY FROM ANY AND ALL CAUSES SHALL BE LIMITED TO THE AMOUNT OF ONE
HUNDRED US DOLLARS ($100.00). EXPORT. Customer agrees that it will not directly or indirectly export the Evaluation Board to another country, and that it will comply with all applicable United States
federal laws and regulations relating to exports. GOVERNING LAW. This Agreement shall be governed by and construed in accordance with the substantive laws of the Commonwealth of Massachusetts
(excluding conflict of law rules). Any legal action regarding this Agreement will be heard in the state or federal courts having jurisdiction in Suffolk County, Massachusetts, and Customer hereby submits
to the personal jurisdiction and venue of such courts. The United Nations Convention on Contracts for the International Sale of Goods shall not apply to this Agreement and is expressly disclaimed.
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