DC1922A - Demo Manual

DEMO MANUAL DC1922A
LTC3129
15V, 200mA Synchronous Buck-Boost DC/DC Converter
with 1.3µA Quiescent Current
Description
Demonstration Circuit 1922A features the LTC®3129, a
high efficiency 200mA buck-boost DC/DC converter with
a wide VIN and VOUT range.
output applications, or to allow operation with VIN down
to 1.92V. Consult the data sheet for more information on
these options.
The DC1922A demo board has two user selectable operating modes: Burst Mode® Operation and Fixed Frequency
PWM (JP3). There is also an accurate programmable
RUN pin which is used to ENABLE the converter (JP1).
The LTC3129 also incorporates a maximum power point
control function which can be enabled (JP2) for applications
where the input source is a solar cell or is high impedance,
such as intrinsically safe applications or high ZOUT thermal
electric generators (TEGs).
The DC1922A demo board also incorporates a connector
(J1) which can be used to connect to a Dust Networks
Mote demo board.
The DC1922A operates with a 2.42V to 15V input voltage
range, and has been designed with the output voltage set
to 5.0V. Once the converter is started the LTC3129 can
operate with VIN as low as 1.92V provided VCC is backfed. The demo board has optional provisions to backfeed VCC (D1) in order to increase efficiency in some 5V
Performance Summary
Figure 1 shows typical demo board efficiency and Figure 2
shows typical step response.
The LTC3129 data sheet has detailed information about
the operation, specification, and applications of the part.
The data sheet should be read in conjunction with this
quick start guide.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
Specifications are at TA = 25°C
PARAMETER
VALUE
Input Voltage Range
2.42V to 15V
VOUT
5.0V
IOUT (See Note 1)
200mA, for VIN > VOUT
Efficiency
See Figure 1
NOTE 1: The demo board output current is a function of VIN. Please refer to the data sheet for more information.
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1
DEMO MANUAL DC1922A
description
DC1922A Efficiency vs Load, VOUT = 5V
100
(AUTOBURST)
EFFICIENCY (%)
80
60
(PWM)
VIN = 3V
VIN = 5V
VIN = 10V
VIN = 15V
VIN = 3V
VIN = 5V
VIN = 10V
VIN = 15V
40
20
0
0.01
0.1
1
10
LOAD (mA)
100
1000
dc1922a F01
Figure 1. DC1922A Efficiency in AUTOBURST MODE
Figure 2. DC1922A Step Response
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DEMO MANUAL DC1922A
Quick Start Procedure
Using short twisted pair leads for any power connections
and with all loads and power supplies off, refer to Figure 3
for the proper measurement and equipment setup. The
power supply (PS1) should not be connected to the circuit
until told to do so in the procedure below.
7. Load current (IOUT) can also be varied. The maximum
IOUT is a function of VIN and the current limit. Consult
the data sheet for more information on IOUT vs VIN.
In general for VIN > VOUT IOUT can be increased to
200mA. For VIN < VOUT IOUT capability will be reduced.
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 4), or by using an oscilloscope probe tip jack.
8. For operation in fixed frequency (PWM) mode move
Jumper JP3 to FIXED FREQ. See the data sheet for
more information on Burst Mode operation.
1. Jumper, PS1 and LOAD settings to start:
For USE with a Solar Cells/MPPC:
PS1 = OFF
JP1 (RUN) = ON
JP2 (MPPC) = OFF
JP3 (PWM) = BURST MODE OPERATION
JP4 (DUST PWR) = NC
2. With power OFF connect the power supply (PS1) as
shown in Figure 3. If accurate current measurements
are desired (for efficiency calculations for example)
then connect an ammeter (AM1) in series with the supply as shown. The ammeter is not required however.
3. Connect a 50mA load to VOUT as shown in Figure 3
(100Ω for VOUT = 5V). Connect an ammeter (AM2) if
accurate current measurement or monitoring is desired.
4. Turn on PS1 and slowly increase voltage until the
voltage at VIN is 4.0V.
5. Verify VOUT is ~5.0V.
6. VIN can now be varied between 2.42V and 15.0V.
VOUT should remain in regulation.
9. NOTE: If VOUT drops out of regulation, check to be
sure that VIN is not below the minimum value for
regulation (see data sheet).
10. With power OFF move jumper MPPC (JP2) to ON.
11. If using a power supply as the source, place a minimum of 10Ω, 10W resistor in series with the input to
simulate the source resistance. If using a solar cell (s)
or high impedance source, no additional resistance
should be needed.
12. Set resistor R9 to a value which will set the MPPC
pin to the desired voltage. See the data sheet section
“Programming the MPPC Voltage” for more information.
13. With no load and the MPPC voltage set, increase the
source voltage above the MPPC set point. VOUT should
be in regulation. As the load is increased VIN will drop
until it reaches the MPPC set voltage. As the load is
increased further, VOUT will drop out of regulation,
but VIN will be regulated to the set point voltage. This
is to prevent the input source from collapsing and to
allow the maximum power to be extracted from the
source.
14. Consult the data sheet for more information on
maximum power point control (MPPC) operation.
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3
DEMO MANUAL DC1922A
Quick Start Procedure
For USE with a DUST Networks MOTE demo board:
15. Connector J1 is designed to interface with a Dust
Networks Mote demo board. Consult the Dust
documentation for optimal VOUT regulation setting.
In general the Dust Networks Mote will operate with
VOUT set to 3.3V. However, care should be taken to
not overvoltage the Mote. Newer Motes may require
a different VOUT. The DC1922A demo board can be
configured for different VOUT voltages by simply
changing R2.
17. Once the output voltage has been set to the proper
voltage and with the power supply OFF connect
DC1922A to the Dust Networks Mote demo board
using J1. See Figure 5 and 6 for the proper connections and orientation. Move jumper JP4 to VOUT.
18. Once the boards have been connected, turn on PS1
and increase the voltage to approximately 3V. VOUT
should now be in regulation. VIN can now be varied
over the operating range and VOUT should remain in
regulation.
16. The DC1922A demo board can be configured for
VOUT = 3.3V by changing resistor R2 to 1.1M for
R1 = 2M.
Figure 3. Proper Measurement Equipment Setup
GND
VIN
Figure 4. Measuring Input or Output Ripple
4
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DEMO MANUAL DC1922A
Quick Start Procedure
Figure 5. DC1922A Connected to DC9003 Dust Mote (Top View)
Figure 6. DC1922A Connected to DC9003 Dust Mote (Bottom View)
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DEMO MANUAL DC1922A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
C1
CAP CER 22µF, 25V, X5R, 20%,1210
TDK, C3225X5R1E226M
2
2
C2, C4
CAP CER 1.0µF, 25V, X5R, 20%, 0603
TDK, C1608X5R1E105M
3
1
C3
CAP CER 22µF, 10V, X5R, 20%, 1210
TDK, C3225X5R1A226M
4
2
C5,C6
CAP CER 22000pF, 50V, X7R, 10%, 0603
TDK, C1608X7R1H223K
5
1
C7
CAP CER 33pF, 50V, 5%, NP0 0603
TDK, C1608C0G1H330J
6
1
C9
CAP CER 2.2µF, 10V, X7R, 20%, 0603
TDK, C1608X7R1A225M
7
1
C10
CAP CER 10pF, 50V, NP0, ±0.25pF 0603
TDK, C1608C0G1H100C
8
1
L1
INDUCTOR, 10µH
COILCRAFT, EPL3015-103
9
1
Q1
N-CHANNEL MOSFET, 20V, SOT23
DIODES/ZETEX, ZXMN2F30FHTA
10
4
R1, R4, R5, R6
RES,CHIP, 2.0M, 1/16W, 1%, 0402
VISHAY, CRCW04022M00FKED
11
1
R2
RES, CHIP, 619k, 1/16W,1%, 0402
VISHAY, CRCW0402619KFKED
12
1
R3
RES, CHIP, 2.21k, 1/16W, 1%, 0402
VISHAY, CRCW04022K21FKED
13
1
U1
15V, 200mA SYNCHRONOUS BUCK - BOOST DC / DC CONVERTER LINEAR TECHNOLOGY, LTC3129EUD
WITH 1.3µA QUIESCENT CURRENT
Additional Demo Board Circuit Components
1
0
C8
CAP TANT 68µF, 20V, 10%, SMD 7343 (OPT)
OPT
2
0
C11
CAP CER 6.3V, 0603 (OPT)
OPT
3
0
D1
DIODE SCHOTTKY (OPT)
OPT
4
0
R7, R8, R9
RES 1/10W, 1%, 0402 SMD (OPT)
OPT
MILLMAX 2501-2-00-80-00-00-07-0
Hardware: For Demo Board Only
1
5
E1, E2, E3, E4, E5
TESTPOINT, TURRET 0.094"
2
1
J1
HEADER, 2 × 6, 12-PIN, SMT HORIZONTAL SOCKET W/KEY, 0.100" SAMTEC, SMH-106-02-L-D-05
3
4
JP1, JP2, JP3, JP4
JMP, 0.079 SINGLE ROW HEADER, 3 PIN
SAMTEC, TMM-103-02-L-S
4
4
XJP1, XJP2, XJP3, XJP4
SHUNT, .079" CENTER
SAMTEC, 2SN-BK-G
5
4
(STAND-OFFS)
STAND-OFF, NYLON 0.625" Tall
KEYSTONE, 8834(SNAP ON)
6
dc1922af
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.
A
B
C
D
JP1
RUN
VIN
R8
OPT
R5
2M
OPT
7343
+ C8
VIN
RUN
C10
10pF
VOUT
C1
22uF
25V
1210
ON
VCC
5
JP2
MPPC
OFF
OPT
D1
C2
1uF
25V
1. ALL RESISTORS ARE IN OHMS, 0402
ALL CAPACITORS ARE IN MICROFARADS, 0603.
NOTE: UNLESS OTHERWISE
SPECIFIED
ON
OFF
GND
E2
2.4V - 15V
VIN
E1
R9
OPT
C11
OPT
6.3V
R7
OPT
BURST MODE
4
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
J.NOON
NC
APPROVALS
JP3
9
8
10
11
7
12
VCC PWM
NC
NC
PWM
PGOOD
FB
VOUT
C6
22nF
50V
PWM
FIXED FREQ
CUSTOMER NOTICE
MPPC
R6
2M
VCC
MPPC
RUN
U1
LTC3129EUD
VCC 3
5
4
VIN
3
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
VIN
C9
2.2uF
MPPC
RUN
2
C5
22nF
50V
1
BST1
16
SW1
GND
6
L1
EPL3015-103
GND
17
13
BST2
14
SW2
PGND
15
4
R2
619k
1%
R1
2M
1%
PGOOD
NC
1
PGOOD
C4
1uF
25V
1
3
5
7
9
11
2
4
6
8
10
12
E4
E5
PGOOD
GND
PGOOD
DATE:
2
01 - 02 - 13
1
1
OF
1
15V, 200mA, SYNCHRONOUS BUCK - BOOST DC / DC
CONVERTER WITH 1.3uA QUIESCENT CURRENT
SIZE
IC NO.
REV.
LTC3129EUD
N/A
2
DEMO CIRCUIT 1922A
SHEET
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
SMH-106-02-L-D-05
NC
VSUPPLY
GND
PGOOD
KEY
VBAT
EHORBAT
RSVD
I/O 2
I/O 1
V+
+5V
J1
CAUTION: ONLY
CONNECT IF VOUT IS
CONFIGURED FOR 3.3V
ZXMN2F30FH
Q1
VOUT
R4
2M
C3
22uF
10V
1210
DATE
01 - 02 - 13
VOUT
5.0V / 200mA
VIN > VOUT
E3
J.NOON
VOUT
APPROVED
DESCRIPTION
1
PRODUCTION FAB
REVISION HISTORY
TECHNOLOGY
JP4
DUST PWR
VOUT
R3
2.21K
TITLE: SCHEMATIC
PWM
2
-
C7
33pF
REV
ECO
2
3
2
5
A
B
C
D
DEMO MANUAL DC1922A
Schematic Diagram
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DEMO MANUAL DC1922A
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
dc1922af
Linear Technology Corporation
LT 0513 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013
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