DC2354A - Demo Manual

DEMO MANUAL DC2354A
LTC7149
60V, Low IQ High Voltage, Negative
Output Monolithic Synchronous Regulator
DESCRIPTION
Demonstration circuit 2354A is a high input voltage,
high efficiency synchronous monolithic step-down converter with negative output featuring the LTC7149. The
DC2354A has wide input voltage range from 3.5V up to
55V. The output voltage of the DC2354A can be set as to
–3.3V or –5V and “User Select” option of DC2354A allows
output voltage to be in a rage from 0V to –60V. However
voltage difference between user-selected negative output
voltage (–VOUT) and maximum input voltage (VIN), should
not exceed 60V. |–VOUT| + VIN < 60V. DC2354A is capable
of delivering up to 4A of output current, nevertheless at
lower input voltage load current should be reduced in
accordance to enclosed derating curves. DC2354A supports three operation modes: Fixed-frequency modulation,
Burst Mode™ operation and user can synchronize it with
external clock also. Fixed-frequency mode of operation
maximizes the output current, reduces output voltage
ripple, and yields a low noise switching spectrum. Burst
Mode operation employs a variable frequency switching
algorithm that minimizes the no-load input quiescent current and improves efficiency at light loads.
PERFORMANCE SUMMARY
PARAMETER
The DC2354A consumes less than 15µA of quiescent current during shutdown and it consumes less than 600µA
at no-load conditions in Burst Mode of operation. The
DC2354A has a standard operating frequency of 500kHz,
but can be adjusted in a range between 300kHz and as
high as 3MHz. LTC7149, which is used in DC2354A, integrates top and bottom N-Channel MOSFETs, significantly
reducing overall circuit footprint. DC2354A was designed
to support multiple footprints of input/output capacitors
and inductors to accommodate variety of applications.
The data sheet of LTC7149 gives a complete description
functionality of this regulator; also contains operation and
application information and must be read in conjunction
with this manual for Demonstration circuit 2354A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2354A
L, LT, LTC, LTM, Linear Technology , the Linear logo and Burst Mode are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
Specifications are at TA = 25°C
CONDITIONS/NOTES
VALUE
Minimum Input Voltage
3.5V
Maximum Input Voltage
55V
Output Voltage VOUT– Regulation
VIN = 3.5V – 60V
–5V ± 2% or –3.3V ± 2%
Maximum Continuous Output Current
VOUT–
4A
Preset Operating Frequency
R10 = 200kΩ
500kHz
External Clock Sync. Frequency Range
300kHz – 3MHz
Efficiency
VIN = 12V, VOUT– = –5V, IOUT = 1A
VIN = 12V, VOUT– = –3.3V, IOUT = 1A
90%
90%
Typical Output Ripple VOUT–
VIN = 12V, VOUT– = –5V, IOUT = 1A (20MHz BW)
<15mVP-P
Quiescent Current at Shutdown
VIN = 3.5V – 55V
<14µA
Input Current at No-Load
VIN = 3.5V – 55V, Burst Mode Operation
<600µA
dc2354af
1
DEMO MANUAL DC2354A
QUICK START PROCEDURE
Demonstration circuit 2354A is easy to set up to evaluate
the performance of the LTC7149. For proper measurement
equipment configuration, set up the circuit according to
the diagram in Figure 1. Before proceeding to test, insert
shunt into JP2 (RUN) into OFF position, which connects
the RUN pin to ground (GND), and thus, shutdown the
output. Set jumper JP1 (MODE) into FCC (Forced Counties Conduction Mode) position. Set jumper JP3 (VOUT–)
into –5.0V position.
NOTE: When measuring the input or output voltage
ripple, care must be taken to avoid a long ground lead
on the oscilloscope probe. Measure the input or output
voltage ripple by touching the probe tip directly across
the VIN or VOUT– and GND terminals. See Figure 2 for
proper scope probe technique.
1.With the DC2354A set up according to the proper
measurement and equipment in Figure 1, apply 16V
at VIN. Measure VOUT–; it should read 0V. If desired,
one can measure the shutdown supply current at this
point. The supply current will be approximately 14µA,
or less, in shutdown.
2.Turn on VOUT– of the circuit by inserting the shunt in
header JP2 (RUN) into the ON position. The output
voltage should be regulating. Measure VOUT– and it
should measure –5.0V ±2%. Vary the current load,
which should not exceed 4A. Vary the input voltage
from 3.5V to 55V, the VOUT–, it should measure –5.0V
±2%. Maximum load current is function of input voltage
and should be changed accordance to derating graphs
on Figure 3.
2
3.Set JP2 (RUN) into OFF and then jumper JP3 (VOUT–)
into –3.3V position.
4. Turn on VOUT2 of the circuit by inserting the shunt in
header JP2 (RUN) into the ON position. The output
voltage should be regulating. Measure VOUT–, it should
measure –3.3V ±2% (do not apply more than the
maximum voltage of 55V to the board or the part may
be damaged). Vary the current load, which should not
exceed 4A. Vary the input voltage from 3.5V to 55V,
the VOUT–, it should measure –3.3V ±2%.
5. Set output current to zero and move jumper JP1 (MODE)
into BURST position and measure VOUT–, which should
be –3.3V ±2%.
6. Set output current to zero and move jumper JP1 (MODE)
into BURST position and measure VOUT–, which should
be –5V ±2%..
DC2354A supports synchronization to external clock
referenced to input GND; use EXT_SYNC terminal for synchronization. PGOOD signal also referenced to input GND,
to activate PGOOD functionality connect external voltage
source to terminals VLOGIC and GND. DC2354A supports
also EXTVCC function, however, EXTVCC is referenced to
VOUT–. Remove R5 and install optional R33 10Ω resistor
if external EXTVCC voltage source is used.
Note: Do not apply more than the maximum voltage of
55V to the board or the part may be damaged.
dc2354af
DEMO MANUAL DC2354A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup
dc2354af
3
DEMO MANUAL DC2354A
QUICK START PROCEDURE
GND
VIN
Figure 2. Measuring Input or Output Ripple
4.0
LOAD CURRENT (A)
3.5
3.0
2.5
2.0
1.5
1.0
–3.3V
–5.0V
0
10
20
30
INPUT VOLTAGE (V)
40
50
DC2354A F03
Figure 3. Output Current vs. Input Voltage Derating Charts
95
EFFICIENCY (%)
90
85
80
75
5V
12V
24V
48V
70
65
0
0.5
1
1.5
2
2.5
LOAD CURRENT (A)
3
3.5
DC2354A F04
Figure 4. Efficiency vs. Load Current for Different Input Voltages
4
dc2354af
DEMO MANUAL DC2354A
QUICK START PROCEDURE
Figure 5. Thermal Map, VIN 48V, VOUT– is –5V at 3.5A, No Air Flow
dc2354af
5
DEMO MANUAL DC2354A
PARTS LIST
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
CIN1
CAP, 1210 2.2μF 10% 100V X7R
TDK C3225C7R1H225K
1
CIN2
CAP, 1210 10μF 10% 63V X7R
MURATA GRM32ER71J106KA12K
1
CIN3
CAP, 10uF 20% 63V ELEC
PANASONIC EEH-ZA1J100P
1
CIN4
CAP, 0805 1μF 10% 100V X7S
TDK C2012X7S2A105K125AB
2
COUT1, COUT2
CAP, 1210 22μF 10% 25V X7R
MURATA GRM32ER71E226KE15L
1
COUT3
CAP, X7R, 22μF, 25V, 1812
TDK, C4532X7R1E226M250KC
1
CTH
CAP, 0603 10nF 10% 50V X7R
AVX 06035A221KAT
1
CTHP
CAP, 0603, 220pF, 10%, 50V, NPO
AVX 06031A101KAT2A
1
CVCC
CAP, 0805 2.2μF 10% 16V X7R
AVX 0805YC225KAT2A
2
C1, C6
CAP, 0603 0.1μF 10% 50V X7R
TDK C1608X7R1H104K080AA
1
C5
CAP, 0603 1μF 20% 25V X7R
TDK C1608X7R1E105M080AB
1
L1
IND, 5.6μH
COILCRAFT XAL5050-562MEB
1
RTH
RES, 0603 511Ω 1% 1/10W
VISHAY CRCW0603511RFKEA
2
R1, R13
RES, 0603 100kΩ 1% 1/10W
VISHAY CRCW0603100KFKEA
1
R2
RES, 0603 10MΩ 1% 1/10W
VISHAY CRCW060310M0FKEA
1
R5
RES, 0603 10Ω 1% 0.1W
VISHAY CRCW060310RFKEA
2
R3, R4
RES, 0603 0Ω JUMPER
VISHAY CRCW06030000Z0EA
1
R10
RES, 0603 200kΩ 1% 1/10W
VISHAY CRCW0603200KFKEA
1
R18
RES, 0805 1MΩ 1% 1/8W
VISHAY CRCW08051M00FKEA
1
R25
RES, 0603 137kΩ 1% 0.063W
VISHAY CRCW0603137KFKEA
1
R26
RES, 0603 1MΩ 1% 1/10W
VISHAY CRCW06031M00FKEA
1
R29
RES, 0603 196kΩ 1% 1/10W
VISHAY CRCW0603196KFKEA
1
R31
RES, 0603 20Ω 1% 0.1W
VISHAY CRCW060320R0FKEA
1
R32
RES, 0603 100Ω 1% 0.1W
VISHAY CRCW0603100RFKEA
1
U1
IC, NEGATIVE OUTPUT REGULATOR
LINEAR TECH. LTC7149EFE28#PBF
R19, R27, R30, R33
RES, 0603 OPTION
OPTION
C3, C4
CAP, 0603 OPTION
OPTION
CIN5
CAP, OPTION
OPTION
Additional Demo Board Circuit Components
Hardware
12
E1, E2, E3, E4, E5, E6, E7, E9, E12, E13, E14, E15
TURRET
MILL MAX 2501-2-00-80-00-00-07-0
3
JP1, JP2, JP3
HEADER, 3-PIN, DBL ROW 2mm
SULLINS, NRPN032PAEN
4
MH1, MH2, MH3, MH4
STANDOFF, SNAP ON
KEYSTONE 8833
3
XJP1, XJP2, XJP3
SHUNT
SAMTEC 2SN-BK-G
6
dc2354af
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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
1
2
3
E12
E9
E13
E1
E2
0
R3
R13
100k
R19 OPT
FCC 1
6
OFF 5
A
JP2
4
EXT I/O 3
6
4
2
2
RUN
JP1
MODE
B
R2
10M
1%
C4
OPT
C3
OPT
R10
200k
1%
RTH
511
1%
CTH
10nF
X7R
6 USER SEL
4 -3.3V
2 -5.0V
R27 OPT
INTVCC
VOUT-
JP3
VOUT-
ON 1
1. ALL CAPACITORS AND RESISTORS ARE 0603.
2. ALL RESISTORS ARE 5%.
3
1
1% 5
1%
EXT 3
BURST 5
R18
1M
1%
0805
VIN
NOTES: UNLESS OTHERWISE SPECIFIED,
GND
PGOOD
VLOGIC
EXT I/O
GND
EXT_SYNC
E7
VOUT-
OPT
R30
196k
R29
100k
R1
B
R25
C1
0.1uF
VOUTSNS
GND
VOUT-
VOUT-
VOUT-
VOUT-
VOUT-
PGDFB
PGOOD
RUN
MODE/SYNC
RT
ITH
ISET
CUSTOMER NOTICE
100 1%
R32 16
R31 20 1% 9
5
4
3
2
1
12
11
8
10
15
18
17
C
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
13
19
21
22
23
24
25
26
27
28
6
7
14
20
CIN4
1uF
0805
100V
R4
0
VOUT-
C5
1uF
25V
i^
SCALE = NONE
`\
PCB DES.
APP ENG.
R5
10
1%
D
DATE:
N/A
SIZE
VOUT-
COUT1
22uF
25V
1210
OPT
+ CIN5
PROD
DESCRIPTION
COUT3
22uF
25V
1812
10uF
63V
+ CIN3
DATE
i ^
APPROVED
VOUT-5V / 4A MAX
GND
GND
VIN
3.5V - 55V
EXTVCC
E15
VOUT-
E14
E6
E5
E4
E3
01/04/16
E
E
LTC7149EFE28
DEMO CIRCUIT 2354A
Monday, March 28, 2016
IC NO.
SHEET 1
OF 1
REV.
3.1
HIGH VOLTAGE, NEGATIVE OUTPUT MONOLITHIC
SYNCHRONOUS REGULATOR
LTC CONFIDENTIAL - FOR CUSTOMER USE ONLY
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
www.linear.com
Fax: (408)434-0507
R33 OPT
COUT2
22uF
25V
1210
CIN2
10uF
63V
1210
VIN
REVISION HISTORY
TECHNOLOGY
TITLE: SCHEMATIC
C6 0.1uF
COILCRAFT
XAL5050-562MEB
L1
5.6uH
CIN1
2.2uF
100V
1210
VOUT-
CVCC
2.2uF
0805
16V
3.1
VOUT-
INTVCC
REV
-
D
ECO
APPROVALS
VOUT-
EXTVCC
BOOST
SW
SW
SW
SW
SW
SW
SW
VIN
VIN
VINREG
INTVCC
U1
LTC7149EFE28
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.
R26
1M
1%
137k 1%
CTHP
220pF
C0G
C
SVOUT-
29
4
A
1
2
3
4
DEMO MANUAL DC2354A
SCHEMATIC DIAGRAM
dc2354af
7
DEMO MANUAL DC2354A
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
8
dc2354af
Linear Technology Corporation
LT 0316 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2016
Similar pages