Analog Devices DC2569A Quick setup guide

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dc2569af
DEMO MANUAL DC2569A
DESCRIPTION
LTM4661
1.8V-5.5V Input,
Synchronous Step-Up µModule Regulator
Demonstration circuit 2569A is ultrathin step-up µModule
regulator featuring the LTM4661. The DC2569A operates
over 1.8V to 5.5V input and it generates 12V, 1A output
from 5V input. Also, the LTM4661 has precision voltage
reference, which can generate output voltage with 3%
tolerance over the full operating conditions. The 1MHz
switching frequency operation results in small and effi-
cient circuit. The converter operates with only one phase
in burst mode and achieves over 90% efficiency with
All registered trademarks and trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
100mA load. The demonstration circuit can be easily
modified to generate different output voltages.
The DC2569 has small circuit footprint. It is a high perfor-
mance and cost effective solution for generating output
voltages up to 15V from inputs as low as 1.8V.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2569A
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Minimum Input Voltage IOUT = 0A to 0.3A 1.8V
Maximum Input Voltage IOUT = 0A to 1A 5.5V
VOUT VIN = 1.8V to 5.5V, IOUT = 0A 12V ±3%
Output Voltage Ripple VIN = 5V, IOUT = 1A 20mVP-P
Nominal Switching Frequency 1MHz
BOARD PHOTO
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DEMO MANUAL DC2569A
QUICK START PROCEDURE
Figure 2. Measuring Input or Output Ripple
Figure 1. Proper Measurement Equipment Setup
+– +–
+
–
+
–
+
–
+
–
LOAD
IOUT IIN
VOUT VIN
LAB
SUPPLY
DC2569A
+ –
V
OUT
GND
COUT
Demonstration circuit DC2569 is easy to set up to evaluate
the performance of the LTM4661. For proper measure-
ment equipment setup refer to Figure 1 and follow the
procedure below:
NOTE:When measuring the input or output voltage ripple,
care must be taken to minimize the length of oscilloscope
probe ground lead. Measure the input or output voltage
ripple by connecting the probe tip directly across the VIN
or VOUT and GND terminals as shown in Figure 2.
1. With power off, connect the input power supply to VIN
and GND.
2. Keep the load set to 0A or disconnected.
3. Turn the input power source on and slowly increase the
input voltage. Be careful not to exceed 5.5V.
NOTE: Make sure that the input voltage VIN does not
exceed 5.5V.
4. Set the input voltage to 5V and check for the proper
output voltage of 12V. 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 voltage is established, adjust
the load and observe the output voltage regulation,
ripple voltage, efficiency and other parameters.
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DEMO MANUAL DC2569A
QUICK START PROCEDURE
CHANGING THE OUTPUT VOLTAGE
To change the output voltage from the programmed
12V, change the voltage setting resistors connected to
LTM4661 FB pin (see the schematic on page 5).
CONVERTER OUTPUT CURRENT
The DC2569 output current capability depends on the
input voltage and programmed input current limit. Typi-
cal performance of DC2569A is shown in Figure 3. As can
be seen from Figure 3, the maximum output current is 1A
with 5V input. Switching the mode of operation to BURST
mode can increase the efficiency at light loads.
Figure 3. The 5V Input Efficiency is 90% at 0.6A Load
Figure 4. Thermal Image, 3.3V Input to 12V Output
at 0.8A, 200LFM Air Flow, No Heat Sink
LOAD CURRENT (A)
0
EFFICIENCY (%)
93
75
91
87
83
79
89
85
81
77
73 10.6
4661 G02
0.80.4
1.2
0.2
VOUT = 12V, 1A DC
OUTPUT LOAD STEP RESPONSE
The load step response of DC2569A is dependent on the
amount and type of output caps used. If higher load steps
need to be handled more output capacitance can be added
in order to keep the voltage transients at the desired level.
The 200mA to 400mA load step transients with 3.3V input
are shown in Figure 5. Other types of low ESR and high
value capacitors can be used if space is available to reduce
load transients to desired level.
Figure 5. The LTM4661 Has Good Load Step Response
with Small Output Capacitors (2×22µF)
500µs/DIV
VOUT (AC)
200mV/DIV
LOAD STEP
200mA
TO 400mA
4661 G05
VIN = 3.3V, VOUT = 12V
fS= 1MHz (DEFAULT)
200mA TO 400mA LOAD STEP
C
OUT
= 2×22µF CERAMIC
START-UP AND SOFT-START FUNCTION
The DC2569 features internal soft-start circuit that ramps
the output voltage up in monotonic fashion. The soft-start
circuit also prevents output voltage overshoot when out-
put voltage ramp reaches regulation.
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DEMO MANUAL DC2569A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 CIN1 CAP.,10µF, X5R, 16V, 20%, 0805 AVX, 0805YD106MAT2A
KEMET, C0805C106M4PAC7800
KEMET, C0805C106M4PACTU
2 1 COUT1, COUT2 CAP., 22µF, X5R, 16V, 20%, 1206 MURATA, GRM31CR61C226ME15L
3 1 COUT3 CAP., 1µF, X5R, 25V, 10%, 0805 AVX, 08053D105KAT2A
4 2 R1, R6 RES., 1MΩ, 1%, 1/10W, 0603 NIC, NRC06F1004TRF
PANASONIC, ERJ3EKF1004V
VISHAY, CRCW06031M00FKEA
5 1 R5 RES., 11k, 1%, 1/10W, 0603 VISHAY, CRCW060311K0FKEA
6 1 U1 IC,Step-Up DC/DC Power Module, LGA-25 LINEAR TECHNOLOGY, LTM4661EV#PBF
Additional Demo Board Circuit Components
1 0 C1, C2, C3 CAP., 0603, OPTION OPT
2 0 R2, R3, R4 RES., OPTION, 0603 OPT
QUICK START PROCEDURE
Figure 6. The DC2569 Ramps the Output Slowly
at Start-Up without Output Voltage Overshoot
500µs/DIV
VIN
2V/DIV
IIN
200mA/DIV
RUN
2V/DIV
VOUT
10V/DIV
4661 G07
VIN = 3.3V,
VOUT = 12V
fS= 1MHz (DEFAULT)
C
OUT
= 2×22µF CERAMIC
OUTPUT SHORT CIRCUIT PROTECTION
The LTM4661 features safe short-circuit and thermal pro-
tection. The part can operate continuously with output
shorted while maintaining a maximum set current limit.
The internal peak switch current is reduced during over-
load to about 2A and is restored to 3.5A once the output
exceeds 1.5V.
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DEMO MANUAL DC2569A
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
STEP UP µMODULE REGULATOR
NOTE: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS AND CAPACITORS ARE 0603
ON OFF
PWM
BURST MODE
RUN
+VIN
1.8V - 5.5V
+VOUT [email protected] GND
GND
*OUTPUT WITH 5V INPUT
*
1%
INTVCC
INTVCC
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
LTM4661EY
Wednesday, June 08, 2016 11
HZ
G.P.
N/A
DEMO CIRCUIT 2569A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
LTM4661EY
Wednesday, June 08, 2016 11
HZ
G.P.
N/A
DEMO CIRCUIT 2569A
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] 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
1
LTM4661EY
Wednesday, June 08, 2016 11
HZ
G.P.
N/A
DEMO CIRCUIT 2569A
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
GP
PROTOTYPE1 5-31-16
_
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
GP
PROTOTYPE1 5-31-16
_
REVISION HISTORY DESCRIPTION DATEAPPROVEDECO REV
GP
PROTOTYPE1 5-31-16
_
R5
11K
E1
R3
OPT
CIN1
10uF
10V
0805
COUT3
1uF
25V
0805
C1 OPT
R4
OPT
JP1
1
2
3
C3 OPT
COUT1
22uF
25V
1206
+
CIN2
OPT
E3 E2
R6
1M
LTM4661EY
U1
VIN
B1
VIN
C1
VIN
E1 VIN
D1
GND
A2
GND
B2
GND
C2
SYNC/MODE
D2
GND
A3
GND
B3
GND
C3
GND
B4
INTVCC D3
FREQ
E3
VIN
A1 VOUT A4
GND
C4
GND
D4
GND
E2
COMP E4
VOUT A5 VOUT B5 VOUT C5
SDB
D5
FB E5
COUT2
22uF
25V
1206
E4
R1
1M
R2
OPT
C2 OPT
JP2
1
2
3
+VIN
INTVCC
+VOUT
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DEMO MANUAL DC2569A
 LINEAR TECHNOLOGY CORPORATION 2017
LT 1117 • PRINTED IN USA
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
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