Linear Technology DC2358A User manual

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DEMO MANUAL DC2358A
DESCRIPTION
LTM8068
Isolated μModule DC/DC Converter
with LDO Regulator
The Demo Circuit 2358A is a 2kV AC isolated flyback
μModule
®
DC/DCconverterwithLDOpostregulatorfeatur-
ing the LTM8068. The demo circuit is designed for a 5.6V
flyback output and a 5V post regulator output from a 4.5V
to 40V input. The current capability of the 5.6V flyback
output varies with input voltage from about 200mA at
4.5VIN to about 460mA at 40VIN. The current capability of
the 5V LDO output is limited by either the current capabil-
ity of VOUT1 minus VOUT1 loading or the 300mA current
limit on the LDO post regulator itself. Figure 1 shows the
maximum output current on VOUT1 when VOUT2 is not
loaded, and VOUT2 when VOUT1 is unloaded. VOUT2 is the
LDO post regulator from VOUT1.
L, LT, LTC, LTM, Linear Technology, the Linear logo and µModule are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
The two-stage converterprovides an isolatedflyback output
as well as a low-noise LDO output. Figure 2 shows the
output noise spectrum on the flyback output and Figure
3 shows the output noise spectrum on the LDO output.
The LTM8068 data sheet gives complete description of
the device, operation and application information. The
data sheet must be read in conjunction with this quick
start guide for demo circuit 2358A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2358A
BOARD PHOTO
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DEMO MANUAL DC2358A
PERFORMANCE SUMMARY
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage 4.5 V
Maximum Input Voltage 40 V
Output Voltage VOUT1 VIN = 4.5V to 40V 5.3 5.6 5.9 V
Output Voltage VOUT2 VIN = 4.5V to 40V 4.85 5 5.15 V
Voltage Ripple VOUT1 VIN = 12V, IOUT1 = 200mA, IOUT2 = 0mA 25 mV
Voltage Ripple VOUT2 VIN = 12V, IOUT1 = 0mA, IOUT2 = 200mA 1 mV
Demo circuit 2358A is easy to set up to evaluate the per-
formance of the LTM8068. Refer to Figure 4 for proper
measurement equipment setup and follow the procedure
below:
NOTE: 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
and GND or VOUT and VOUTN terminals. See Figure 5 for
proper scope probe technique.
1. With power off, connect the input power supply to VIN
and GND.
2. Turn on the power at the input.
NOTE. Make sure that the input voltage does not
exceed 40V.
3. Check for the proper output voltages. (For OUT1, check
the voltage between VOUT1 and VOUTN. For OUT2, check
the voltage between VOUT2 and VOUTN.)
NOTE: If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
4. Once the proper output voltages are established, adjust
the load within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters.
QUICK START PROCEDURE
Specifications are at TA= 25°C
Figure 1. Maximum Output Current vs
VIN: 5.6VOUT1 Flyback Output with VOUT2
Unloaded; 5VOUT2 LDO output with
VOUT1 Unloaded
Figure 2. VOUT1 Output Noise Spectrum
with IOUT1 at 200mA and VIN at 12V
(VOUT2 Has No Extra Load)
Figure 3. VOUT2 Output Noise Spectrum
with IOUT2 at 200mA and VIN at 12V
(VOUT1 Has No Extra Load)
VIN (V)
0
MAXIMUM LOAD CURRENT (mA)
500
100
300
400
200
0
dc2358 F01
40
2010 30
5.6VOUT1
5VOUT2
FREQUENCY (MHz)
0
INTENSITY (dBm)
0
–80
–40
–20
–60
–100 2.5 4.51.5 3.5
dc2358 F02
5.0
2.0 4.01.0 3.00.5
FREQUENCY (MHz)
0
INTENSITY (dBm)
0
–80
–40
–20
–60
–100 2.5 4.51.5 3.5
dc2358 F03
5.0
2.0 4.01.0 3.00.5
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DEMO MANUAL DC2358A
QUICK START PROCEDURE
Figure 4. DC2358A Proper Equipment Setup
Figure 5. Measuring Input or Output Ripple
INPUT OR OUTPUT CAPACITOR
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DEMO MANUAL DC2358A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 CIN1 CAP., ALUM, 22µF, 50V, 6.6x6.6mm NICHICON, UUD1H220MCL1GS
2 1 C1 CAP., CER., 10µF, X7R, 50V, 10%, 1210 MURATA, GRM32ER71H106KA12L
3 2 C2, C3 CAP., CER., 4.7µF, X5R, 10V, 10%, 0603 MURATA, GRM188R61A475KE15D
4 1 C4 CAP., CER., 47µF, X5R, 10V, 10%, 1206 MURATA, GRM31CR61A476KE15L
5 1 C5 CAP., CER., 22µF, X5R, 6.3V, 20%, 0805 MURATA, GRM21BR60J226ME39L
6 1 C8 CAP., CER., 0.01µF, X7R, 25V, 10%, 0603 MURATA, GRM188R71E103KA01D
7 1 C10 CAP., CER., 10pF, NP0, 50V, 5%, 0603 MURATA, GRM1885C1H100JA01D
8 1 R1 RES, 200k, 1/10W, 1%, 0603 VISHAY, CRCW0603200KFKEA
9 1 R2 RES, 95.3k, 1/10W, 1%, 0603 VISHAY, CRCW060395K3FKEA
10 1 R3 RES, 7.32k, 1/10W, 1%, 0603 VISHAY, CRCW06037K32FKEA
11 1 R4 RES, 604Ω, 1/8W, 1%, 0805 VISHAY, CRCW0805604RFKEA
12 1 R5 RES, 162k, 1/10W, 1%, 0603 VISHAY, CRCW0603162KFKEA
13 1 U1 I.C., LTM8068EY#PBF 9 × 11.25 × 4.92 BGA LINEAR TECH., LTM8068EY#PBF
Additional Demo Board Circuit Components
1 0 C6 (OPT) CAP., 1210 (OPT)
2 0 C7 (OPT) CAP., 0805 (OPT)
3 0 C9 (OPT) CAP., 1808 (OPT)
4 0 L1 (OPT) IND., 10µH, XFL3012 (OPT)
Hardware: For Demo Board Only
1 6 E1-E6 TESTPOINT, TURRET, 0.094" pbf MILL-MAX, 2501-2-00-80-00-00-07-0
2 1 E7 TEST POINT, TURRET, 0.064" MTH HOLE MILL-MAX, 2308-2-00-80-00-00-07-0
3 4 MH1-MH4 STAND-OFF, NYLON 0.375" SNAP ON KEYSTONE, 8832
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DEMO MANUAL DC2358A
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
A
A
B
B
C
C
D
D
E
E
4 4 3 3 2 2 1 1
4.5V - 40V
FOR INPUT VOLTAGE DAMPING PURPOSE ONLY.
1%
5V
5.6V
*
1. ALL RESISTORS ARE 0603. ALL CAPACITORS ARE 0603. NOTE: UNLESS OTHERWISE SPECIFIED
*
** SEE QUICK START GUIDE FOR OUTPUT CURRENT RANGE.
**
**
VINVIN
E2
GND
E3
VOUT1
R5
162k
R4 604 0805
C6
OPT
1206
R1 200k
C2
4.7uF
10V
C1
10uF
1210
50V
C10
10pF C9
OPT 1808
E1
VIN
C4 47uF 10V 1206
C8 0.01uF 25V
E7
RUN
C3
4.7uF
10V
+
22uF 50V CIN1 22uF
E4 VOUTN E5
VOUT2
L1
OPT
U1
LTM8068EY
RUN
F3
GND
E4
GND
H5
VOUT1 A6
GND
H6
VIN
G1
GND
F7
FB2 A2
VOUTN A3
VIN
H1
GND
E5
GND
E6
GND
E7
GND
F4
GND
F5
GND
F6
GND
G4
GND
G5
GND
E3
VOUTN A4 VOUTN A5 VOUTN B3 VOUTN B4 VOUTN B5
VOUT1 A7 VOUT1 B6 VOUT1 B7
VIN
G2
VIN
H2
BYP B2
VOUT2 B1 VOUT2 A1
FB1
G7
GND
G6
GND
H4
GND
E2 GND
E1
GND
H7
R2
95.3k
E6 VOUTN
R3
7.32k
C5
22uF
6.3V
0805
C7
OPT
0805
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DEMO MANUAL DC2358A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2016
LT 0216 • 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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