DC2195B - Demo Board Manual

DEMO MANUAL DC2195B
LT8609/LT8609A
42V, 2A Micropower Synchronous
Step-Down Regulator
DESCRIPTION
Demonstration circuit 2195B is a 42V, 2A micropower
synchronous step-down regulator featuring the LT8609/
LT8609A. There are two assembly versions. DC2195B-A
is for the LT8609A and DC2195B-B is for the LT8609.
The difference is the LT8609A has slower edge speeds
for improved EMI at the expense of a small efficiency loss.
The demo board is designed for 5V output from a 5.5V to
42V input. The wide input range allows a variety of input
sources, such as automotive batteries and industrial supplies. The LT8609/LT8609A is a compact, high efficiency,
high speed synchronous monolithic step-down switching
regulator that consumes only 2.5μA of quiescent current
when output is regulated at 5V. Top and bottom power
switches, compensation components and other necessary
circuits are inside of the LT8609 to minimize external
components and simplify design.
The SYNC pin on the demo board is grounded by default
for low ripple burst mode operation. Move JP1 to PULSE
SKIPPING position can change the operation mode to pulseskipping operation. Once JP1 is on SPREAD SPECTRUM
position, VCC is applied to the SYNC pin for low EMI spread
spectrum operation. To synchronize to an external clock,
move JP1 to SYNC and apply the external clock to the
SYNC turret. Figure 1 shows the efficiency of the circuit.
The demo board has an EMI filter installed. Under spread
spectrum operation, the radiated EMI performances of
the board (with EMI filter) are shown in Figures 2 and
3. The red lines in Figures 2 and 3 are CISPR25 Class 5
peak limit. To use the EMI filter, the input should be tied
to VEMI, not VIN. An inductor L2, which is a 0Ω jumper
on the board by default now, can be added in the EMI filter
to further reduce the conducted emission.
This board is suitable for a wide range of automotive,
telecom, industrial, and other general purpose applications.
The LT8609/LT8609A data sheet gives a complete description of the part, operation and application information. The
data sheet must be read in conjunction with this demo
manual for DC2195B.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2195B
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
Specifications are at TA = 25°C
SYMBOL
PARAMETER
CONDITIONS
VIN
Input Voltage Range
5.5
VOUT
Output Voltage
4.8
IOUT
Maximum Output Current
MIN
TYP
5
MAX
42
V
5.2
V
2
1.85
UNITS
A
fSW
Switching Frequency
EFE (LT8609A)
Efficiency for DC2195B-A
VIN = 12V, IOUT = 1A
92.1
2
2.15
MHz
%
EFE (LT8609)
Efficiency for DC2195B-B
VIN = 12V, IOUT = 1A
92.9
%
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DEMO MANUAL DC2195B
QUICK START PROCEDURE
DC2195B is easy to set up to evaluate the performance of
the LT8609/LT8609A. Refer to Figure 4 for proper measurement equipment setup and follow the procedure below:
a. If efficiency measurements are desired, an ammeter
can be put in series with the output load in order to
measure the DC2195B’s output current.
NOTE: When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. See Figure 5 for the proper scope
technique.
b.A voltmeter can be placed across the output terminals
in order to get an accurate output voltage measurement.
1.Set an input power supply that is capable of 42V/2A.
Then turn off the supply.
2.With power off, connect the supply to the input terminals
VEMI and GND.
3.Turn on the power at the input.
NOTE: Make sure that the input voltage never exceeds 42V.
4.Check for the proper output voltage of 5V. Turn off the
power at the input.
5.Once the proper output voltage is established, connect
a variable load capable of sinking 2A at 5V to the output
terminals VOUT and GND. Set the current for 0A.
6.Turn on the power at the input.
NOTE: If there is no output, temporarily disconnect the
load to make sure that the load is not set too high.
7.Once the proper output voltage is again established,
adjust the load and/or input within the operating range
and observe the output voltage regulation, ripple voltage, efficiency and other desired parameters.
8.An external clock can be added to the SYNC terminal
when SYNC function is used (JP1 on the SYNC position). Please ensure that the chosen RT sets the LT8609/
LT8609A switching frequency to equal or below the
lowest SYNC frequency. See the data sheet section,
“Synchronization.”
100
95
90
EFFICIENCY (%)
85
80
75
70
65
60
55
50
LT8609A
LT8609
0
0.5
1
IOUT (A)
1.5
2
DC2195 F01
Figure 1. Efficiency vs Load Current at 12V Input 2MHz Switching Frequency
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DEMO MANUAL DC2195B
QUICK START PROCEDURE
Figure 2. LT8609A Demo Circuit EMI Performance in CISPR25 Radiated Emission Test (VIN = 14V, VOUT =
5V, IOUT = 2A, 2MHz Switching Frequency)
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DEMO MANUAL DC2195B
QUICK START PROCEDURE
Figure 3. LT8609 Demo Circuit EMI Performance in CISPR25 Radiated Emission Test (VIN = 14V, VOUT = 5V,
IOUT = 2A, 2MHz Switching Frequency)
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DEMO MANUAL DC2195B
QUICK START PROCEDURE
Figure 4. Proper Measurement Equipment Setup
VOUT
GND
Figure 5. Measuring Output Ripple
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DEMO MANUAL DC2195B
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
1
C2
CAP., X7R, 4.7µF, 50V, 10%, 1206
MURATA, GRM31CR71H475K
2
1
C4
CAP., X7R, 0.22µF, 16V, 10%, 0603
AVX, 0603YC224KAT2A
3
1
C5
CAP., C0G, 10pF, 25V, 5%, 0603
AVX, 06033A100JAT2A
4
1
C6
CAP., X7R, 47µF, 10V, 10%, 1210
MURATA, GRM32ER71A476KE20L
5
1
C7
CAP., X7R, 1.0µF, 25V, 10%, 0603
MURATA, GRM188R71E105KA12D
6
1
C8
CAP., X7R, 0.01µF, 16V, 10%, 0603
AVX, 0603YC103KAT2A
7
1
L1
IND., 2.2µH
COILCRAFT, XFL4020-222MEC
8
1
R2
RES., CHIP, 18.2k, 1/10W, 1%, 0603
VISHAY, CRCW060318K2FKEA
9
1
R3
RES., CHIP, 49.9k, 1/10W, 1%, 0603
VISHAY, CRCW060349K9FKEA
10
2
R1, R4
RES., CHIP, 1M, 1/10W, 1%, 0603
VISHAY, CRCW06031M00FKEA
11
1
R5
RES., CHIP, 187k, 1/10W, 1%, 0603
VISHAY, CRCW0603187KFKEA
IC, REGULATOR, MSE10
LINEAR TECH., LT8609AEMSE#PBF
IC, REGULATOR, MSE10
LINEAR TECH., LT8609EMSE#PBF
DC2195B-A Version Specific Components
1
1
U1
DC2195B-B Version Specific Components
1
1
U1
Additional Demo Board Circuit Components
1
1
C1
CAP., ALUM 22µF, 63V
SUN ELECT, 63CE22BS
2
2
C3, C10
CAP., X7R, 4.7µF, 50V, 10%, 1206
MURATA, GRM31CR71H475K
3
1
C9
CAP., X7R, 4.7µF, 16V, 10%, 0805
MURATA, GRM21BR71C475K73L
4
1
C11
CAP., X7R, 1µF, 50V, 10%, 0805
TDK, C2012X7R1H105K
5
2
C12, C13
CAP., X7R, 0.1µF, 50V, 10%, 0603
MURATA, GRM188R71H104KA93D
6
1
FB1
FERRITE BEAD 0805
TDK, MPZ2012S221A
7
1
L2
RES., CHIP, 0Ω, 3/4W, 2010
VISHAY, CRCW20100000Z0EF
8
0
R6 (OPT.)
RES., 0603
Hardware: For Demo Board Only
1
9
E1-E9
TESTPOINT, TURRET, 0.094"
2
1
E10 (OPT.)
TESTPOINT, TURRET, 0.094"
MILL-MAX, 2501-2-00-80-00-00-07-0
3
1
JP1
DOUBLE ROW HEADER 2 × 4 0.079"
SULLINS NRPN042PAEN-RC
4
1
XJP1
SHUNT, 0.079" CENTER
SAMTEC 2SN-BK-G
5
4
MH1-MH4
STAND-OFF, NYLON 0.50" TALL
KEYSTONE, 8833 (SNAP ON)
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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.
A
B
C
GND
VEMI
5.5V - 42V
VIN
5.5V - 42V
E2
E1
E10
5
E9
E7
VCC
E5
E6
C12
0.1µF
50V
4
6
8
5
7
2
3
1
JP1
C3
4.7µF
50V
1206
+
C1
22µF
63V
SUNCON
63CE22BS
BURST
PULSE SKIPPING
SPREAD SPECTRUM
SYNC
C10
4.7µF
50V
1206
L2
0 2010
1. ALL RESISTORS ARE 0603.
ALL CAPACITORS ARE 0603.
4
NOTES: UNLESS OTHERWISE SPECIFIED
GND
TR/SS
SYNC
EN/UV
C11
1µF
50V
0805
FB1
4
C7
1µF
C2
4.7µF
50V
1206
C8
0.01µF
VCC
C13
0.1µF
50V
R2
18.2k
(2MHz)
R6
(Opt)
R1
1.00M
3
4
7
3
5
10
9
3
RT
TR/SS
VCC
SYNC
EN/UV
VIN
U1 *
GND
11
D
5
L1
2.2µH
LT8609EMSE
DC2195B-B
2
LT8609AEMSE
U1
R5
187k
49.9k
R3
10pF
C5
1.00M
R4
XFL4020-222MEC
C4
0.22µF
DC2195B-A
VERSIONS
6
8
2
1
* FOR ASSEMBLY
FB
PG
SW
BST
2
VOUT
C6
47µF
10V
1210
1
1
E8
E4
C9 E3
4.7µF
16V
0805
PG
GND
VOUT
5V / 2A
A
B
C
D
DEMO MANUAL DC2195B
SCHEMATIC DIAGRAM
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DEMO MANUAL DC2195B
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
dc2195bf
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Linear Technology Corporation
LT 0216 REV B • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2016
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