DC2255A - Demo Manual

DEMO MANUAL DC2255A
LTC3106EUDC
300mA, Low Voltage Buck-Boost Converter with
PowerPath and 1.6µA Quiescent Current
DESCRIPTION
Demonstration circuit DC2255A features the LTC®3106,
an ultralow input voltage buck-boost DC/DC converter
with automatic PowerPath™ management optimized for
multisource, low power systems. Burst Mode® operation
architecture allows the LTC3106 to run very efficiently with
as little as 1.6µA of input current at no load.
Programmable accurate RUN threshold as well as maximum power point control (MPPC) allow for simple optimization of power transfer between the power source and
the input supply to the DC2255A. Selectable peak current
limit (100mA or 725mA) also allows the LTC3106 to adapt
to a wide variety of input supplies.
An accurate RUN threshold voltage of VIN = 1.2V is set
by positioning the shunt on JP12 in the middle position.
This threshold is set by the values of R4 and R5. For
maximum power point control setpoint above 0.6V, it is
usually better to use the accurate RUN functionality. See
the data sheet for more details. Maximum power point
control is enabled by setting JP5 to VCC. The value of R3
sets the MPPC threshold.
The DC2255A has four user selectable output voltages:
1.8V, 2.2V, 3.3V and 5V. When the LTC3106 is enabled,
the PGOOD pin asserts low if VOUT is below the regulation
voltage. If JP3 is set to VOUT the red PGOOD indicator LED
on the board lights up when the output is in regulation.
PERFORMANCE SUMMARY
SYMBOL
PARAMETER
This is a visual indication of VOUT being in regulation and
is not needed for normal operation. To minimize current
consumed, set JP3 to NC.
The LTC3106 can operate with either a primary or secondary battery on its VSTORE supply. In secondary mode
(JP7 set to GND), the part will use excess power to trickle
charge the battery on VSTORE. There are four pin selectable
OV/UV thresholds for the battery voltage in this mode to
allow operation with a variety of secondary batteries. If
the DC2255A is operated in secondary mode, a Schottky
diode must be placed between the SW2 and VAUX pins.
The LTC3106 requires no external compensation and
provides good line and load transient response across
the entire VIN range for each output voltage setting. This
simplifies the design process while reducing the external
component count.
The LTC3106 data sheet has detailed information about
the operation, specifications, 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/DC2255A
L, LT, LTC, LTM, Linear Technology, the Linear logo, Dust and Burst Mode are registered
trademarks and PowerPath is a trademark of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
Specifications are at TA = 25°C
CONDITIONS
MIN
TYP
0.350
VIN
2.1
VSTORE
VOUT
1.8V, 2.2V, 3.3V and 5V Selectable Output Voltages
IOUT
VIN > VOUT
Efficiency
Option
Dependent
300
MAX
UNITS
5.1
V
4.3
V
V
mA
See Figures 1, 2
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DEMO MANUAL DC2255A
PERFORMANCE SUMMARY
90
90
80
80
EFFICIENCY (%)
100
EFFICIENCY (%)
100
70
60
50
40
0.1
VIN = 1.2V
VIN = 1.8V
VIN = 2.5V
VIN = 3.3V
VIN = 4V
VIN = 5V
1
10
LOAD (mA)
70
60
50
100
40
0.01
1000
dc2255a F01
VSTORE = 3V
VSTORE = 4V
0.1
1
10
LOAD (mA)
100
1000
dc2255a F02
Figure 1. DC2255A Efficiency vs Load with Part Running
from VIN. VOUT = 3.3V
Figure 2. DC2255A Efficiency vs Load with Part
Running from VSTORE Input. VOUT = 3.3V
VAUX
VAUX
VOUT
VOUT
IL
IL
dc2255a F03
Figure 3. DC2255A Normal VAUX, VOUT and Inductor Current
Behavior. The Middle VOUT Charging Period Terminates Early
to Charge Up VAUX Because VAUX Takes Priority Over VOUT
dc2255a F04
Figure 4. DC2255A Load Step Response. VIN = 3V, VOUT = 3.3V,
Load Step is from 40mA to 200mA
dc2255af
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DEMO MANUAL DC2255A
QUICK START PROCEDURE
Using short twisted pair leads for any power connections
and with all loads and power supplies off, refer to Figure 5
for the proper measurement and equipment setup. The
power supplies (PS1 and PS2) 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 oscilloscope probe. Measure the input or output voltage ripple
by touching the probe tip directly across the VIN, VSTORE
or VOUT and GND terminals (see Figure 6), or by using
an oscilloscope probe tip jack.
3. Connect a 3.3mA load (1kΩ) to VOUT as shown in
Figure 5. Connect an ammeter in series if accurate
current monitoring is desired.
4. Turn on PS1 and slowly increase the voltage until the
voltage at VIN is 1.2V.
5. Verify VOUT is ~3.3V.
6. VIN can now be varied between 600mV and 5.1V. VOUT
should remain in regulation. If VIN is brought below
600mV, it will have to be brought back up above 1.2V
to start up again.
1. Jumper, Battery, PS1 and PS2 settings to start:
7. Turn PS1 off.
JP1, JP3:
NC
JP2:
VSTORE
8. Turn on PS2 and slowly increase voltage until voltage
at VSTORE is 2.5V.
JP4, JP5, JP7, JP8, JP10, JP11: VCC
JP6:
VSTORE
JP9:
GND
JP12:
BYPASS
Battery in BTH1 (CR2032):
Not Populated
PS1:
OFF
PS2:
OFF
2. With power OFF connect the power supplies (PS1,
PS2) as shown in Figure 5. If accurate current measurements are desired (for efficiency calculation for
example) then connect ammeters in series with the
supplies as shown. The ammeters are not required
however.
9. Verify VOUT is ~3.3V.
10.VSTORE can now be varied between 2.1V and 4.3V.
11.If desired, turn off PS2 and populate BTH1 on the back
of the board with a CR2032 or connect a different
suitable battery (2.1V to 4.3V) to VSTORE.
NOTE1: Connector J1 is used to connect DC2255A to a
Dust® Mote (see Figure 7). If unused, set JP1 to NC.
NOTE2: Connector J2 is used to facilitate connection to
a solar cell PCB or other power supply board. Use of J2
is not required however, and solar cells or other suitable
power sources can be connected directly to the VIN or
VSTORE terminal on the DC2255A.
CAUTION: DO NOT POWER VSTORE FROM AN EXTERNAL
SUPPLY WITH A BATTERY IN BTH1.
dc2255af
3
DEMO MANUAL DC2255A
QUICK START PROCEDURE
Figure 5. Proper Measurement and Equipment Setup
VIN
GND
Figure 6. Measuring Input or Output Ripple
dc2255af
4
DEMO MANUAL DC2255A
QUICK START PROCEDURE
Figure 7. DC2255A Top and Bottom View of DC2255A Connected to Dust Mote.
dc2255af
5
DEMO MANUAL DC2255A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
CAP CER 1µF 16V 10% X7R 0805
TDK, C2012X7R1C105K125AA
Required Circuit Components
1
2
C1, C12
2
6
C2, C3, C4, C5, C6, C16 CAP CER 100µF 6.3V 20% X5R 1210
SAMSUNG, CL32A107MQVNNNE
3
1
C10
CAP CER 2.2µF 10V 20% X5R 0805
TDK, C2012X5R1A225M085AA
4
1
C11
CAP CER 47µF 10V 20% X5R 1210
SAMSUNG, CL32A476MPJNNNE
5
1
C14
CAP CER 0.1µF 6.3V 10% X7R 0805
KEMET, C0805C104K9RACTU
6
3
R1, R4, R5
RES 1M 1/10W 1% 0603 SMD
PANASONIC, ERJ-3EKF1004V
7
1
R2
RES., CHIP, 4.99k, 1/10W, 0603
PANASONIC, ERJ-3EKF4991V
8
1
R3
RES 301k 1/10W 1% 0603 SMD
PANASONIC, ERJ-3EKF3013V
9
1
D2
LED 0402 RED 50mW 20mA SMD
ROHM, SML-P11VTT86
10
1
L1
INDUCTOR, SHIELDED 10µH
COILCRAFT, LPS4018-103
11
1
Q1
MOSFET N-CHAN 20V SOT23-3
DIODES INC, ZXMN2F30FHTA
12
1
U1
300mA, LOW VOLTAGE BUCK-BOOST CONVERTER WITH
PowerPath AND 1.6µA QUIESCENT CURRENT
LINEAR TECHNOLOGY, LTC3106EUDC#PBF
Additional Demo Board Circuit Components
13
0
C7, C8, C9, C13
1210 CASE SIZE
14
0
D1
DIODE SCHOTTKY 20V, 1A
NXP, PMEG2010EA
15
0
C15
CAP 100µF –20% +80% 5.5V T/H
EATON BUSSMANN, KR-5R5H104-R
Hardware: For Demo Board Only
16
1
BATTERY
CR2032 COIN CELL BATTERY
DURACELL, CR2032
17
1
BTH1
CR2032 COIN CELL BATTERY HOLDER, SMD
WURTH, 79527141
18
8
E1-E8
TESTPOINT, TURRET, 0.095"
MILL-MAX, 2501-2-00-80-00-00-07-0
19
11
JP1-JP11
3 PIN 0.079 SINGLE ROW HEADER
SAMTEC, TMM-103-02-L-S
20
12
JP1-JP12
SHUNT
SAMTEC, 2SN-BK-G
21
1
JP12
4 PIN 0.079 SINGLE ROW HEADER
WURTH, 62000411121
22
4
(STAND-OFFS)
STAND-OFF, NYLON 0.75" TALL
KEYSTONE, 8834(SNAP ON)
23
1
J1
HEADER, 2X6, 12-PIN, SMT HORIZONTAL SOCKET W/KEY, 0.100" SAMTEC, SMH-106-02-L-D-05
24
1
J2
CONN RECEPT 20POS 0.50" SMT
SAMTEC, SFMH-110-02-L-D-WT
dc2255af
6
B
A
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.
JP3
LED
E7
+
1
JP8
OS1
C15
OPT
JP12
VCC
BYPASS
VIN
R_STRING
VSTORE
PGOOD
PGOOD
NC
VOUT
VSTORE
2.1V - 4.3V
VCC
GND
GND
E3
VIN
350mV-5.1V
E2
VIN
GND
OS1
C16
100uF
6.3V
1210
1
3
5
7
9
11
13
15
17
19
BTH1
VCC
GND
R4
VCC
1M
JP9
NC
R5
1M
GND
VCC
1
JP10
C2
100uF
6.3V
1210
VSTORE
GND
VOUT
C12
1uF
16V
0805
JP6
SS1
GND
GND
VCC
VCC
JP11
SS2
ENVSTR
VSTORE
C14
0.1uF
6.3V
0805
4
19
14
20
11
13
16
1
L1 10uH
SS2
VCC
VCAP
ENVSTR
GND
VCC
JP7
PRI
U1
LPS4018-103
VSTORE
PRI
RUN
VIN
NC
LTC3106EUDC
VCC
ENVSTR
PRI
RUN
C1
1uF
16V
0805
ENVSTR
VSTORE
C11
47uF
10V
1210
VSTORE
VCC
SS1
C3
100uF
6.3V
1210
VIN
2
4
6
8
10
12
14
16
18
20
OPT
C13
1210
JP2
VCAP
C4
100uF
6.3V
1210
VSTORE
OS2
C5
100uF
6.3V
1210
VCAP
OS2
VSTORE
VIN
RUN
Q1
ZXMN2F30FH
+
VOUT
IO1
IO2
NC
NC
GND
VLDO
V+
VBAT
NC
SFMH-1-10-02-L-D-WT
+5V
PGOOD
VCAP
NC
NC
NC
EHORBAT
GND
RSVD
VIN
J2
D2
SML-P11VTT86
R2
4.99k
VOUT
VCAP
PGOOD
1
2
3
2
1
2 I
18
SW1
GND
21
17
R3
301k
SS2
SS1
OS2
OS1
JP5
MPPC
VCC
R1
1M
NC
VOUT
JP1
DUST PWR
R3
VCC
JP4
ILIMSEL
VCC
GND
C10
2.2uF
10V
0805
CUSTOMER NOTICE
8
12
9
10
6
5
7
2
3
VAUX
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
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.
PRI
MPP
ILIMSEL
SS2
SS1
OS2
OS1
PGOOD
VOUT
VCC
D1 OPT
PMEG2010EA
VAUX
SW2
GND
15
1
2
4
6
8
10
12
SCALE = NONE
NC
JIM N.
PCB DES.
APP ENG.
4.2V
4.0V
3.0V
2.9V
4.0V
2.1V
3.0V
2.15V
1.9V
2.78V
VSTORE UV
GND
GND
PGOOD
GND
GND
E8
VCC
VCC
GND
GND
5.0V
3.3V
2.2V
1.8V
VOUT
DATE:
N/A
SIZE
2
11-20-15
IC NO.
SHEET 1
2
REV.
OF 1
300mA, LOW VOLTAGE BUCK-BOOST CONVERTER WITH
POWERPATH and 1.6uA QUIESCENT CURRENT
LTC3106EUDC
DEMO CIRCUIT 2255A
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
VCC
GND
VCC
GND
OS2
DATE
11-20-15
VOUT
E6
E5
E4
E1
JIM N.
APPROVED
VOUT JUMPER CONFIGURATION
OS1
*
TECHNOLOGY
GND
VCC
VCC
GND
GND
VCC
TITLE: SCHEMATIC
SMH-106-02-L-D-05
VSUPPLY NC
GND PGOOD
KEY
VBAT
RSVDEHORBAT
I/O 2
I/O 1
+5V
V+
APPROVALS
1
3
5
7
9
11
VCC
GND
GND
VCC
GND
GND
GND
GND
VSTORE OV
VSTORE JUMPER CONFIGURATION
SS2
GND
VOUT
PGOOD
C9
OPT
1210
SS1
*
C8
OPT
1210
DESCRIPTION
REVISION HISTORY
PRODUCTION FAB
PRI
1210
C7
OPT
2
-
CAUTION: ONLY CONNECT IF
VOUT IS LESS THAN 3.7V.
PGOOD
J1
VOUT
C6
100uF
1210
REV
ECO
2
B
A
DEMO MANUAL DC2255A
SCHEMATIC DIAGRAM
dc2255af
7
DEMO MANUAL DC2255A
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
dc2255af
8
Linear Technology Corporation
LT 0116 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
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