Linear Technology LTC3129 Quick setup guide

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DEMO MANUAL DC1922A
Description
LTC3129
15V, 200mA Synchronous Buck-Boost DC/DC Converter
with 1.3µA Quiescent Current
Demonstration Circuit 1922A features the LT C
®
3129, a
high efficiency 200mA buck-boost DC/DC converter with
a wide VIN and VOUT range.
The DC1922A demo board has two user selectable operat-
ing 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
controlfunctionwhichcanbeenabled(JP2)forapplications
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 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 back-
fed. The demo board has optional provisions to back-
feed VCC (D1) in order to increase efficiency in some 5V
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.
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 also incorporates a connector
(J1) which can be used to connect to a Dust Networks
Mote demo board.
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
performance summary
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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DEMO MANUAL DC1922A
Description
Figure 1. DC1922A Efficiency in AUTOBURST MODE
DC1922A Efficiency vs Load, VOUT = 5V
Figure 2. DC1922A Step Response
VIN = 15V
VIN = 10V
VIN = 5V
VIN = 3V
VIN = 10V
VIN = 5V
VIN = 15V
VIN = 3V
(PWM)
LOAD (mA)
0.01
0
EFFICIENCY (%)
80
20
60
40
100
10 100 10000.1
dc1922a F01
1
(AUTOBURST)
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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.
When measuring the input or output voltage ripple, care
must be taken to avoid a long ground lead on the oscil-
loscope 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 oscil-
loscope probe tip jack.
1. Jumper, PS1 and LOAD settings to start:
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)
thenconnectanammeter(AM1)inserieswiththesup-
ply 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
accuratecurrentmeasurementormonitoringis
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.
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 willbe reduced.
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.
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).
For USE with a Solar Cells/MPPC:
10. With power OFF move jumper MPPC (JP2) to ON.
11. If using a power supply as the source, place a mini-
mum 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 informa-
tion.
13. With no load and the MPPC voltage set, increase the
sourcevoltage above the MPPCset 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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DEMO MANUAL DC1922A
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.
16. The DC1922A demo board can be configured for
VOUT = 3.3V by changing resistor R2 to 1.1M for
R1 = 2M.
Quick start proceDure
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 connec-
tions 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.
GND VIN
Figure 3. Proper Measurement Equipment Setup
Figure 4. Measuring Input or Output Ripple
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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
WITH 1.3µA QUIESCENT CURRENT
LINEAR TECHNOLOGY, LTC3129EUD
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
Hardware: For Demo Board Only
1 5 E1, E2, E3, E4, E5 TESTPOINT, TURRET 0.094" MILLMAX 2501-2-00-80-00-00-07-0
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)
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DEMO MANUAL DC1922A
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 CC
B B
A A
1%
ON
OFF
RUN MPPC
ON
OFF
PWM
BURST MODE
FIXED FREQ
1%
2.4V - 15V
NOTE: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE IN OHMS, 0402 ALL CAPACITORS ARE IN MICROFARADS, 0603.
CAUTION: ONLY CONNECT IF VOUT IS CONFIGURED FOR 3.3V
VIN > VOUT
NC
DUST PWR
VOUT
VCC
VIN
VIN VIN
VCC
VOUT
PWM
VCC MPPC
MPPC
PWM
RUN
RUN
VOUT
PGOOD
PGOOD
PGOOD
VOUT
SIZE
DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035
Phone: [phone]
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
2
DEMO CIRCUIT 1922A
11
CONVERTER WITH 1.3uA QUIESCENT CURRENT
N/A
LTC3129EUD
NC
J.NOON
01 - 02 - 13
15V, 200mA, SYNCHRONOUS BUCK - BOOST DC / DC
SIZE
DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035
Phone: [phone]
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
2
DEMO CIRCUIT 1922A
11
CONVERTER WITH 1.3uA QUIESCENT CURRENT
N/A
LTC3129EUD
NC
J.NOON
01 - 02 - 13
15V, 200mA, SYNCHRONOUS BUCK - BOOST DC / DC
SIZE
DATE:
.VER.ONCI
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035
Phone: [phone]
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
2
DEMO CIRCUIT 1922A
11
CONVERTER WITH 1.3uA QUIESCENT CURRENT
N/A
LTC3129EUD
NC
J.NOON
01 - 02 - 13
15V, 200mA, SYNCHRONOUS BUCK - BOOST DC / DC
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
J.NOONPRODUCTION FAB
- 2 01 - 02 - 13
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
J.NOONPRODUCTION FAB
- 2 01 - 02 - 13
REVISION HISTORY
DESCRIPTION DATEAPPROVEDECO REV
J.NOONPRODUCTION FAB
- 2 01 - 02 - 13
JP2JP2
C2 1uF
25V
C2 1uF
25V
E5
PGOOD
E5
PGOOD
R2 619k R2 619k
JP3JP3
E3
VOUT
5.0V / 200mA
E3
VOUT
5.0V / 200mA
C3 22uF 10V
1210
C3 22uF 10V
1210
U1
LTC3129EUD
U1
LTC3129EUD
GND
6
VIN
2
SW1 16
BST213
FB 7
RUN
4
VCC
3
PWM 10
PGND
15
GND
17
MPPC
5PGOOD 11
SW2 14
BST11
VOUT 12
NC 8
NC 9
R7
OPT
R7
OPT
C4 1uF
25V
C4 1uF
25V
C11 OPT 6.3V C11 OPT 6.3V
C5 22nF
50V
C5 22nF
50V
R8
OPT
R8
OPT
E4
GND
E4
GND
R9
OPT
R9
OPT
R3 2.21K R3 2.21K
C6 22nF 50V C6 22nF 50V
Q1 ZXMN2F30FH Q1 ZXMN2F30FH
3
1
2
D1
OPT
D1
OPT
E1
VIN
E1
VIN
L1
EPL3015-103
L1
EPL3015-103
R6 2M R6 2M
JP4JP4
C7
33pF
C7
33pF
C1
22uF
25V
1210
C1
22uF
25V
1210
R4 2M R4 2M
+
C8
OPT 7343
+
C8
OPT 7343
C10 10pF C10 10pF
C9
2.2uF
C9
2.2uF
J1
SMH-106-02-L-D-05
J1
SMH-106-02-L-D-05
VSUPPLY
1NC 2
GND
3PGOOD 4
KEY
5VBAT 6
RSVD
7EHORBAT 8
I/O 2
9I/O 1 10
+5V
11 V+ 12
R5
2M
R5
2M
E2
GND
E2
GND
JP1JP1
R1 2M R1 2M
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DEMO MANUAL DC1922A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2013
LT 0513 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) 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 LT C 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 LT C 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. LT C assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LT C 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 LT C applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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