Linear Technology LT8390A Quick setup guide

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dc2598af
DEMO MANUAL DC2598A
DESCRIPTION
LT8390A
60V 2MHz Synchronous
Buck-Boost Controller
Demonstration circuit 2598A is a 60V 2MHz synchronous
buck-boost controller featuring the LT
®
8390A. It accepts
an input voltage from 4V to 24V (with transient to 60V) and
regulates 12V output at up to 4A. DC2598A features high
efficiency and 2MHz switching frequency, a high speed
for a 4-switch buck-boost controller. It has a PGOOD flag,
short-circuit fault protection, ISMON current-monitoring
output signal, and spread spectrum frequency modulation
(SSFM) or frequency synchronization.
The LT8390A has a wide input voltage range from 4V to
60V. It can regulate an output as a boost, a buck, or a
4-switch boost-buck controller. It has adjustable switch-
ing frequency between 600kHz and 2MHz. It has an option
for external frequency synchronization or spread spec-
trum frequency modulation. Its high switching frequency
is unique to buck-boost controller ICs. Because of this, it
can be used for high power when the input may be above,
below, or equal to the output.
DC2598A features an option to turn on spread spectrum
by simply changing the position of a jumper from “NO
SSFM/SYNC” to “SSFM” (or to ”SYNC”).
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Analog
Devices, Inc. All other trademarks are the property of their respective owners.
PERFORMANCE SUMMARY
Small ceramic input and output capacitors are used to
save space and cost. There is a protection diode from
LED+ to GND to prevent negative ringing during a short-
circuit with long wires. Optional EMI input, output, and
gate resistor component placeholders exist when a low
EMI application is needed.
Under voltage lockout can be adjusted with a few resistors
and output voltage can be changed from 12V with FB resis-
tors changes. Please note that higher voltage outputs may
require higher voltage MOSFETs and output capacitors.
The LT8390A data sheet gives a complete description of the
part, operation and applications information. The data sheet
must be read in conjunction with this demo manual for
demonstration circuit 2598A. The LT8390AEUFD is assem-
bled in a 28-lead 4mm × 5mm plastic QFN package with a
thermally enhanced ground pad. LT8390A is also available
in a 28-Lead plastic TSSOP (FE) package. Proper board
layout is essential for maximum thermal performance. See
the data sheet section “Layout Considerations”.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2598A
Specifications are at TA= 25°C
PARAMETER CONDITION MIN TYP MAX
Input Voltage Range Operating 4V 60V
Full Load (4A) Input Voltage Range Component Temp Rise <60°C with No Airflow 7V 23V
Typical Efficiency 12V Input, 12V 4A Output, 2MHz 90%
Switching Frequency R3 = 59.0k 2MHz
Peak Switch Current Limit R1 = 0.005Ω 10A
(AC) Output Ripple 12V Input, 12V 4A Output 70mVP-P
Input Under Voltage Lockout (Falling Turn-Off) R7 = 383k, R8 = 165k 4.0V
Input Under Voltage Lockout (Rising Turn-On) R7 = 383k, R8 = 165k 5.0V
VISMON 12V 4A Output 1.0V
Maximum Load Current 12V Input, 12V Output 4 4.5A
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DEMO MANUAL DC2598A
QUICK START PROCEDURE
Figure1. Test Procedure Setup Drawing For DC2598A
Demonstration circuit 2598A is easy to set up to evaluate
the performance of the LT8390A Follow the procedure
below:
1. With the input power supply off, connect the input
power supply and output load as shown in the test
setup drawing in Figure 1.
2. Connect the EN/UVLO terminal to GND.
3. Make sure that the SSFM jumper is in the correct posi-
tion – either with SSFM turned ON or OFF. Only place
the jumper in the SYNC position if an external SYNC
frequency source is connected to the SYNC pin.
4. Turn the input power supply on and make sure the
voltage is between 4V and 24V for proper steady state
operation.
5. Release the EN/UVLO-to-GND connection.
6. Observe the 12V output voltage, the load current mea-
surement via the ISMON pin voltage and the high effi-
ciency of this small converter.
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DEMO MANUAL DC2598A
Figure2. DC2598A, LT8390A 2MHz Buck-Boost Efficiency 12VOUT
QUICK START PROCEDURE
Figure 3. Recommended Maximum DC Current with No Airflow (for DC2598A)
LOAD CURRENT (A)
2
2.5
3
3.5
4
0
10
20
30
40
50
60
70
80
90
100
EFFICIENCY (%)
dc2598a F02
0
0.5
1
1.5
24VIN
12VIN
9V
6V
VIN (V)
0
5
10
15
20
25
30
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
IOUT (A)
dc2598a F03
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DEMO MANUAL DC2598A
Figure4. DC2598A, LT8390A Output Ripple Measured at C45
Figure5. DC2598A, LT8390A Bode Plot 12V Input, 12V 4A Output
QUICK START PROCEDURE
Mag [B/A] (dB)
50.000
-50.000
40.000
30.000
20.000
10.000
0.000
-10.000
-20.000
-30.000
-40.000
Phase [B-A] (deg)
150.000
-150.000
120.000
90.000
60.000
30.000
0.000
-30.000
-60.000
-90.000
-120.000
1 kHz 10 kHz 100 kHz 1 MHz
12
05/16/17 16:58:30
M1 M2 M2 - M1
Frequency 30.57 kHz 367.03 kHz 336.46 kHz
Magnitude -0.000 dB -20.562 dB -20.562 dB
Phase 75.120 deg 0.871 deg -74.249 deg
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DEMO MANUAL DC2598A
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 C1 CAP., 1μF, X7S, 100V, 10%, 0805
2 1 C2 CAP., 4.7μF, X5R, 10V, 10%, 0402 TDK, C1005X5R1A475K050BC
3 1 C3 CAP., 0.47μF, X5R, 16V, 10%, 0402 TAIYO YUDEN, EMK105ABJ474KV-F
4 1 C4 CAP., 2200pF, X7R, 25V,1 0%, 0402 MURATA, GRM155R71E222KA01D
6 1 C5 CAP., 0.022μF, X7R, 25V, 10%, 0402 MURATA, GRM155R71E223KA61D
7 1 C6 CAP., 1μF, X7R, 25V, 10%, 0603 KEMET, C0603C105K3RACTU
5 2 C7, C8 CAP., 0.1μF, X7R, 25V, 10%, 0402 AVX, 04023C104KAT2A
8 1 C10 CAP., 22μF, ALUM, 63V, 20%, SMD 6.3mm × 7.7mm SUN ELECTRONIC INDUSTRIES CORP, 63CE22FS
9 2 C12, C32 CAP., 4.7μF, X7S, 100V, 20%, 1206 AVX, 12061Z475MAT2A
10 3 C14, C20, C45 CAP., 22μF, X5R, 25V, 10%, 1206 MURATA, GRM31CR61E226KE15L
16 2 D1, D2 DIODE, SCHOTTKY, 100V, 250mA, SOD-323F,
AEC-Q101
NXP SEMICONDUCTORS, BAT46WJ
25 1 L1 IND., 1μH, Power Shielded, 20%, 7.3A, 6mm × 5.5mm WURTH ELEKTRONIK, 74437336010
27 2 M1, M2 XSTR., POWER MOSFET, 60V, 40A, TSDSON-8 INFINEON, BSZ065N06LS5ATMA1
29 2 M3, M4 XSTR., POWER MOSFET, 25V, 40A, TSDSON-8 INFINEON, BSZ031NE2LS5ATMA1
31 1 R1 RES., 0.005Ω, ±1%, 1.5W, 3216, AEC-Q200 SUSUMU, KRL3216E-C-R005-F-T1
32 1 R2 RES., 0.01Ω, 1%, 3/4W, 1206, SENSE SUSUMU, KRL1632E-M-R010-F-T5
33 1 R3 RES., 59k, 1%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW040259K0FKED
34 2 R4, R6 RES., 10k, 1%, 1/16W, 0402 VISHAY, CRCW040210K0FKED
35 1 R5 RES., 110k, 1%, 1/16W, 0402 VISHAY, CRCW0402110KFKED
36 1 R7 RES., 383k, 1%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW0402383KFKED
37 1 R8 RES., 165k, 1%, 1/16W, 0402, AEC-Q200 VISHAY, CRCW0402165KFKED
40 1 R11 RES., 100k, 5%, 1/16W, 0402 VISHAY, CRCW0402100KFKED
45 1 U1 IC, 2MHz SYN. BUCK-BOOST CONTROLLER,
28-PIN QFN
LINEAR TECH., LT8390AEUFD#TRPBF
Optional Electrical Components
5 3 C37, C38, C44 CAP., 0.1μF, X7R, 25V, 10%, 0402 AVX, 04023C104KAT2A
11 0 C26, C34, C39 CAP., OPTION, 0402
12 1 C27 CAP., 1μF, X5R, 16V, 10%, 0402 AVX, 0402YD105KAT2A
13 0 C29, C30 CAP., 0805, OPTION
14 0 C33, C40, C41, C42 CAP., OPTION, 1206
15 2 C35, C36 CAP., 0.1μF, X5R, 100V, 10%, 0402 MURATA, GRM155R62A104KE14D
17 1 D3 DIODE, SCHOTTKY, 20V, 1A, SOD-323F NXP SEMICONDUCTORS, PMEG2010EJ
18 0 D4, D5 DIODE, OPTION, SCHOTTKY, SMD
22 0 FB1, FB2, FB3, FB4, FB5, FB6 IND., OPTION, BEAD, FERRITE, 1206
26 0 L2 IND., OPTION, XAL4020 SERIES
30 0 Q1 XSTR., OPTION, PPAK 1212-8
PARTS LIST
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DEMO MANUAL DC2598A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
38 1 R9 RES., 124k, 1%, 1/16W, 0402 VISHAY, CRCW0402124KFKED
39 1 R10 RES., 75k, 1%, 1/16W, 0402 VISHAY, CRCW040275K0FKED
41 0 R12, R20, R21, R25, R28,
R29, R30
RES., OPTION, 0402
42 6 R14, R15, R16, R17, R24, R26 RES., 0Ω, 1/16W, 0402, AEC-Q200 VISHAY, CRCW04020000Z0ED
43 2 R18, R19 RES., 10Ω, 5%, 1/16W, 0402 VISHAY, CRCW040210R0FKED
44 0 R22, R23, R27 RES., OPTION, 0805
Hardware
19 4 E1, E2, E9, E10 TEST POINT, TURRET, 0.094", MTG. HOLE MILL-MAX, 2501-2-00-80-00-00-07-0
20 6 E3, E4, E5, E6, E7, E8 TEST POINT, TURRET, 0.064", MTG. HOLE MILL-MAX, 2308-2-00-80-00-00-07-0
21 0 E11 TEST POINT, OPTION
23 1 JP1 CONN., HDR, MALE, 2mm × 3,2mm, THT, STR WURTH ELEKTRONIK, 62000621121
24 4 J1, J2, J3, J4 CONN., BANANA JACK, FEMALE, THT, NON-
INSULATED, SWAGE
KEYSTONE, 575-4
28 4 MH1, MH2, MH3, MH4 STANDOFF, NYLON, SNAP-ON, 0.375" WURTH ELEKTRONIK, 702933000
46 1 XJP1 CONN., SHUNT, FEMALE, 2 POS, 2mm WURTH ELEKTRONIK, 60800213421
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dc2598af
DEMO MANUAL DC2598A
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
VIN
4V - 60V EN/UVLO
GND
ALL CAPACITORS ARE 0402. NOTE: UNLESS OTHERWISE SPECIFIED
2MHz
ALL RESISTORS ARE 0402.
12V 4A OUT
PGOOD
ISMON
SYNC
GND
CTRL
OPT EMI FILTER
GND
*
*SEE DEMO MANUAL
LOADEN
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
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.
www.linear.com
3
DC2598A
Tuesday, May 23, 2017 11
60V 2MHz SYNCHRONOUS BUCK-BOOST CONTROLLER
N/A
LT8390AEUFD
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
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.
www.linear.com
3
DC2598A
Tuesday, May 23, 2017 11
60V 2MHz SYNCHRONOUS BUCK-BOOST CONTROLLER
N/A
LT8390AEUFD
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
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.
www.linear.com
3
DC2598A
Tuesday, May 23, 2017 11
60V 2MHz SYNCHRONOUS BUCK-BOOST CONTROLLER
N/A
LT8390AEUFD
M1
BSZ065N06LS5
E9
R7 383K
FB1 OPT 1206
C20 22uF 1206 25V
C41
R22 OPT
0805
C32 4.7uF
1206 100V
U1
LT8390AEUFD
EN/UVLO 6
PGOOD
14
TEST
7
CTRL
10
LOADEN 8
ISP 11
SYNC/SPRD
19
SS
15
LOADTG
20
VC
17
RT
18
VREF
9
ISMON
13
LSN 3
LSP 2 ISN 12
FB 16
TG2 22
SW2 23
BG2 25 BG1 26
SW1 28
TG1 1
BST1 27 BST2 24
VIN 4
INTVCC
5
GND
29
VOUT 21
R19
10
R5
110K
1%
C34 OPT
JP1
SSFM ON SYNC NO SSFM/SYNC
SYNC/SSFM
1 5 3
2 4 6
C39 OPT
R3
59.0K
R6 10.0K
D3
PMEG2010EJ
D5
OPT
C42
C30 OPT
0805
R11
100K
C27 1uF
D4
OPT
R25 OPT
E5
C45
22uF 1206
25V
R29
OPT
R12 OPT
R4 10K
+
C10
22uF
63V
63CE22FS
C4 2.2nF
C6 1uF
25V 0603
C14 22uF 1206 25V
C5
22nF
FB2
R14 0
J3
L1
1.0uH
74437336010
R1
0.005
KRL3216
1 3 2 4
R27
OPT 0805
FB3
R26
0
C1 1uF 100V 0805
C33 OPT
1206
R28
OPT
R17
0
R16
0
R18
10
C2 4.7uF
10V
C35 0.1uF 0402 100V
FB4
C7
0.1uF
R20 OPT
R10
75.0K
1%
L2
OPT
XEL4020
C37
0.1uF
25V
M3
BSZ031NE2LS5
C26 OPT
E6
FB5
1206
C8 0.1uF
C3
0.47uF R23
OPT 0805
C36 0.1uF 0402 100V
C38
0.1uF
25V
J4
FB6
OPT
E4
E11 OPT
J2
R9 124K
E10
J1
C29
OPT
0805
E7
R15
0
D1 BAT46WJ
C40
E2
R24
0
R21
OPT
R2
0.01
1206
E3
M2
BSZ065N06LS5
Q1 OPT
4
5 6 7
1 2 38
R30 OPT
M4
BSZ031NE2LS5
R8
165K
E1
E8
D2 BAT46WJ
C12 4.7uF
1206 100V
C44 0.1uF
25V
ISP ISN
INTVCC
INTVCC
VREF
VREF
VREF
INTVCC
LOADTG
LOADTG
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DEMO MANUAL DC2598A
 LINEAR TECHNOLOGY CORPORATION 2017
LT 0717 • 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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