Linear Technology DC2120A User manual

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dc2120af
DEMO MANUAL DC2120A
Description
LT3048-15
Low Noise Bias Generator
Demonstration circuit 2120A features the LT3048-15, a
Boost DC/DC Converter with integrated Schottky diode and
LDO in a 2mm ×2mm DFN package. This demo board is
designed to convert a 2.7V to 4.8V input to a 15V output
at 19mA to 35mA with low output ripple and noise. The
LT3048-15 is programmed for 2MHz switching frequency.
This demonstration board can be used to evaluate other
fixed output voltage versions of the LT3048.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
performance summary
The LT3048 data sheet gives a complete description of
the part, operation, and application information. The data
sheet must be read in conjunction with this Quick Start
Guide for the demo circuit DC2120A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2120A
Specifications are at TA= 25°C
Figure 1. DC2120A Efficiency
PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Supply Range 2.7 4.8 V
Output Voltage Range VIN = 2.7V, IOUT = 19mA 14.625 15 15.375 V
Switching Frequency 1.7 2.2 2.7 MHz
Output Ripple VIN = 4.8V, Load = 37mA 1 mV
OUTPUT CURRENT (mA)
2
EFFICIENCY (%)
80
70
50
60
40
20
30
10 10 186 14 26
dc2120a F01
3822 30 34
2.7VIN
4.8VIN
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DEMO MANUAL DC2120A
Quick start proceDure
Demonstration circuit 2120A is easy to set up to evalu-
ate the performance of the LT3048. Refer to Figure 2 for
proper measurement equipment setup and follow the
procedure below:
NOTE. When measuring the output voltage ripple, connect
a X1 oscilloscope probe as shown in Figure 3.
1. Place jumper in the following positions: JP1 Run
2. With power off, connect the input power supply to VIN
and GND.
3. Turn on the power at the input.
NOTE. Make sure that the input voltage does not
exceed 4.8V.
4. Connect a 20mA load from VOUT to GND and check for
the proper output voltage. VOUT = 14.625V to 15.375V
If there is no output, temporarily disconnect the load
to make sure that the load is not set too high.
5. Once the proper output voltages are established, adjust
the input voltage and load within the operating range
and observe the output voltage regulation, ripple volt-
age, efficiency and other parameters.
Figure 2. Proper Measurement Equipment Setup
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DEMO MANUAL DC2120A
Quick start proceDure
Figure 3. Output Ripple Measurement Technique
Figure 4. Output Voltage Ripple
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DEMO MANUAL DC2120A
parts List
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP., X7R, 4.7µF, 25V, 10%, 0805 TDK, C2012X7R1E475K
2 1 C2 CAP., X7R, 2.2µF, 25V, 10%, 0805 TDK, C2012X7R1E225K
3 1 C4 CAP., X7R, 1µF, 25V, 10%, 0603 TDK, C1608X7R1E105K
4 1 C3 CAP., C0G, 1nF, 25V, 5%, 0603 MURATA GRM1885C1E102JA01D
5 1 L1 INDUCTOR, 10µH COOPER Bussmann, SD3110-100-R
6 1 U1 IC., LT3048EDC-15#PBF, DFN-2X2, 8 LEAD LINEAR TECH., LT3048EDC-15#PBF
7 1 FAB, PRINTED CIRCUIT BOARD DEMO BOARD 2120A
Additional Demo Board Circuit Components
1 1 C5 CAP., X7R, 1µF, 25V, 10%, 0603 TDK, C1608X7R1E105K
Hardware: For Demo Board Only
1 4 E1-E4 TESTPOINT, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 1 JP1 3 PIN 0.079" SINGLE ROW HEADER SULLINS, NRPN031PAEN-RC
3 1 XJP1 SHUNT, 0.079" CENTER SAMTEC, 2SN-BK-G
4 1 STENCIL STENCIL DC2120A
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DEMO MANUAL DC2120A
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 C C B B A A
1. ALL RESISTORS ARE 0603. ALL CAPACITORS ARE 0603. NOTE: UNLESS OTHERWISE SPECIFIED
COPPER BUSSMANN SD3110-100-R
*
*
Vin (V) Iout (mA)
2.7 3.3
3.6
19 22 24
4.8 37
C4
1uF
25V
C4
1uF
25V
C2
2.2uF
25V
0805
C2
2.2uF
25V
0805 E2
VOUT
15V
E2
VOUT
15V
C5
1uF 25V
C5
1uF 25V
C3
1nF
C3
1nF
JP1
RUN ON
OFF
JP1
RUN ON
OFF
1
2
3
E4 GND E4 GND
L1
10uH
L1
10uH
U1
LT3048EDC-15
U1
LT3048EDC-15
SW 1
BYP 4
BSTOUT 8
EN
7
VIN
2
GND
9
LDOIN 6
LDOOUT 5
GND
3
E1
VIN
2.7V - 4.8V E1
VIN
2.7V - 4.8V
C1 4.7uF
25V
0805
C1 4.7uF
25V
0805
E3
GND
E3
GND
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DEMO MANUAL DC2120A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2014
LT 0314 • 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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