DC1893A - Demo Manual

DEMO MANUAL DC1893A
LT3697
USB 5V, 2.5A Output, 35V Input
with Cable Drop Compensation
DESCRIPTION
Demonstration circuit 1893A is a USB 5V, 2.5A output,
35V input buck with cable drop compensation featuring the
LT®3697. The LT3697 is a step-down switching regulator
designed to power 5V USB applications.
up a load. VSYS can also be used to supply a 100mA load.
When probing the board, pay attention to GND and C_GND.
On the demonstration board, they are connected together by
default through R13 so a user can connect the ground clip
of a probe to C_GND. However, if a user wants to evaluate
an actual cable, the cable will replace R4 and R13. The
copper between pads of R13 should be cut open. In this
case, C_GND is no longer the same as GND. A differential
measurement is needed to probe across the point of load.
A precise output voltage and programmable cable drop
compensation maintain accurate 5V regulation at the USB
socket at the end of a long cable. The circuit was designed
to run at 500kHz to avoid the AM band. The demo board
has an EMI filter installed. The radiated EMI performance of
the board is on Figures 3 to 5, showing the circuit passes
CISPR25 Class 5 with a wide margin.
The demonstration board also includes a USB socket.
With the proper configuration of jumpers X1, X2, X3 and
X4, the USB can be configured for different applications.
See Table 1 for configurations. A 500mA onboard step
load can also be activated to evaluate the load transient
response of the circuit. To activate the step load, simply set
jumper X5 to V+. The LT3697 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 demo circuit 1893A.
This USB converter was optimized for a maximum VCABLE
of 5V at 2.4A, enough for all USB applications. If higher, or
lower load current is needed, please read the Cable Drop
Compensation paragraph in the Applications section of
the data sheet, and adjust all pertinent component values
as needed. Always ensure the converter stays within the
guaranteed switch current and the output voltage never
exceeds 6.1V. If higher VCABLE voltage is needed, please
refer to Applications example on the data sheet. If VCABLE
is not connected to any load, VOUT can be used to power
Design files for this circuit board are available at
http://www.linear.com/demo/DC1893A
L, LT, LTC, LTM, Linear Technology and tthe 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 Supply Range
VCABLE
Output Voltage
Max IOUT
Maximum Output Current
MIN
MAX
35
V
5
5.2
V
8
4.8
UNITS
2.4
IOUT = 2.4A, Measured at VOUT
Efficiency
TYP
Switching Frequency
A
90
%
500
kHz
Table 1. Configure X1–X4 for Different USB Applications
X1
X2
X3
X4
J3
DO NOT CARE
DO NOT CARE
DO NOT CARE
OPEN
NOT IN USE
OPEN
OPEN
SHORT
SET
USB–DCP
D+
D−
OPEN
SET
USB APPLE 2.4A
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DEMO MANUAL DC1893A
QUICK START PROCEDURE
Demonstration circuit 1893A is easy to set up to evaluate the performance of the LT3697. Refer to Figure 1 for
proper equipment setup and follow the procedure below:
1. With power off, connect the input power supply to VIN
and GND.
2. With power off, connect the load to VCABLE and C_GND.
3. Set X1–X5 to OPEN positions.
4. Turn on the power at the input.
5. Carefully evaluate other design parameters as needed.
6. If a USB device is to be connected to J3, use Table 1
as a guide to set X1–X4 for different USB applications.
The total current provided at J3 and VCABLE should not
exceed 2.4A.
7. Set X5 to V+ if a quick transient test is desired. The load
step applied to VCABLE is 500mA. Again, make sure the
total load current does not exceed 2.4A during the test.
Figure 1. Proper Equipment Setup
GND
VIN
Figure 2. Measuring Output Ripple
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DEMO MANUAL DC1893A
QUICK START PROCEDURE
Figure 3. CISPR25, Class 5, Radiated Disturbances ALSE. Vertical Polarization
Figure 4. CISPR25, Class 5, Radiated Disturbances ALSE. Horizontal Polarization
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DEMO MANUAL DC1893A
QUICK START PROCEDURE
Figure 5. CISPR25, Class 5, Radiated Disturbances ALSE. Vertical Polarization
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DEMO MANUAL DC1893A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART #
Required Circuit Components
1
1
C1
CAP., ALUM, 22µF, 63V, 25%
SUN ELECT. 63CE22BS
2
3
C2, C7, C8
CAP., X7R, 4.7µF, 50V, 10% 1206
MURATA, GRM31CR71H475KA12L
3
1
C3
CAP., X7R, 1uF, 50V, 10% 0805
AVX, 08055C105KAT2A
4
1
C4
CAP., X7R, 47µF, 10V, 10% 1210
MURATA, GRM32ER71A476KE15L
5
1
C13
CAP., X7R, 10nF, 25V, 10% 0402
MURATA, GRM155R71E103KA01D
6
3
C15 to C17
CAP., X7R, 0.1µF, 50V, 10% 0402
TDK, C1005X7R1H104K
7
1
C18
CAP., C0G, 330pF, 50V, 10% 0603
MURATA, GRM1885C1H331JA01D
8
1
C19
CAP., C0G, 1nF, 50V, 5% 0603
AVX, 06035A102JAT2A
9
1
C26
CAP., ALUM, 120µF, 16V, 20%
SUN ELECT. 16HVP120M
10
1
D1
DIODE, CMDSH-3, SOD-323
CENTRAL SEMI., CMDSH-3TR
11
1
D2
RECTIFIER, 3A, 40V, SMA
ON SEMI., MBRA340T3G
12
1
FB1
FERRITE BEAD, BEAD 0805
TDK MPZ2012S221AT
13
5
X1–X5
HEADERS, SGL. ROW 3 PINS 2mm CTRS.
SULLINS NRPN031PAEN-RC
14
5
xX1–xX5
SHUNT, 2mm CTRS.
SAMTEC 2SN-BK-G
15
1
J3
USB, RIGHT ANGLE, RECEPTACLE
CNC TECH, LLC, 1002-001-01000
16
1
L1
IND., 10µH, NRS8040 TYPE
TAIYO YUDEN, NRS8040T100MJGJV
17
1
L2
IND., 22µH
TAIYO YUDEN, NRS8040T220MJGJV
18
1
Q1
POWER MOSFET, SOT23
DIODES INC, ZXMN3A14FTA
19
1
R1
RES., CHIP, 100k, 1/10Ω, 5% 0603
VISHAY CRCW0603100K0JNEA
20
3
R2, R6, R22
RES., CHIP, 100k, 0.06Ω, 5% 0402
VISHAY CRCW0402100KJNED
21
1
R3
RES., 0.022, 0.25Ω, 1% 1206
VISHAY WSL1206R0220FEA
22
1
R4
RES., SENSE, 0.3, 2Ω, 1% 0830
SSM THIN FILM TECH. RL7520WT-R30-F
23
2
R5, R23
RES., POWER, 18, 1Ω, 1% 2512
SSM THIN FILM TECH. CPA2512Q18R0FS-T10
24
1
R7
RES., CHIP, 14.7k, 0.1Ω, 1% 0603
VISHAY CRCW060314K7FKEA
25
1
R9
RES., CHIP, 10k, 0.06Ω, 5% 0402
VISHAY CRCW040210K0JNED
26
1
R10
RES., CHIP, 174k, 0.1Ω, 1% 0603
VISHAY CRCW0603174KFKEA
27
1
R12
RES., CHIP, 7.5k, 0.1Ω, 5% 0603
VISHAY CRCW06037K50JNEA
28
2
R15, R16
RES., CHIP, 43.2k, 0.1Ω, 1% 0603
VISHAY CRCW060343K2FKEA
29
2
R17, R18
RES., CHIP, 49.9k, 0.1Ω, 1% 0603
VISHAY CRCW060349K9FKEA
30
1
R19
RES., CHIP, 10k, 0.1Ω, 5% 0603
VISHAY CRCW060310K0JNEA
31
1
R20
RES., CHIP, 2M, 0.1Ω, 1% 0603
VISHAY CRCW06032M00FKEA
32
2
R21, R24
RES., CHIP, 2, 0.25Ω, 5% 1206
VISHAY CRCW12062R00JNEA
33
1
U1
IC., LT3697EMSE, MSE-16
LINEAR TECH., LT3697EMSE#PBF
34
1
U2
I.C., OSCILLATOR, TSOT-23-S5
LINEAR TECH., LTC6900CS5#PBF
35
1
DEMO CIRCUIT 1893A, REV 3
dc1893af
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.
5
DEMO MANUAL DC1893A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART #
Additional Demo Board Circuit Components
1
0
C9 (OPT)
CAP., 1206
2
1
C10
CAP., X7R, 0.1µF, 25V, 10% 0603
TDK, C1608X7R1E104K
3
2
C11, C12
CAP., X7R, 1µF, 25V, 10% 0805
TDK, C2012X7R1E105K
4
1
C14
CAP., X7R, 2.2nF, 10V, 10% 0603
AVX, 0603ZC222KAT2A
5
0
C25 (OPT)
CAP., 1210
6
0
R13
RES., CHIP, 1206
7
0
R8, R14 (OPT)
RES., 0402
8
0
R25 (OPT)
RES., 0603
Hardware: For Demo Board Only
1
13
E1-E13
TURRET, TESTPOINT
MILL-MAX, 2501-2-00-80-00-00-07-0
2
4
E14-E17
TESTPOINT, TURRET, 0.061" PBF
MILL-MAX, 2308-2-00-80-00-00-07-0
3
4
MH1-MH4
STAND-OFF, NYLON, 0.375"
KEYSTONE, 8832 (SNAP ON)
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6
A
B
C
D
GND
VIN
8V - 35V
E2
E1
E8
E6
E4
E11
C16
0.1µF
50V
100k
R6
C8
4.7µF
50V
1206
R7
14.7k
0603
R22
100k
C7
4.7uF
50V
1206
FB1
+
C18
330pF
0603
R12
7.5k
0603
C19
1nF
0603
C1
22µF
63V
SUNCON
63CE22BS
5
1. ALL RESISTORS ARE 0402.
ALL CAPACITORS ARE 0402.
NOTES: UNLESS OTHERWISE SPECIFIED
RCBL
GND
SYNC
EN
C15
0.1µF
50V
VIN
L2
22µH
NR8040T220M
4
R25
OPT
0603
C2
4.7µF
50V
1206
R20
2M
0603
OPT
R8
C17
0.1µF
50V
FLT
3
SET
R10
174k
0603
R2
100K
6
8
7
9
5
3
2
1
2
4
RT
OUT
10k
0603
5 R19
C14
2.2nF
0603
U2
LTC6900CS5
V+
3
1
USB5V
SYS
ISN
ISP
SW
SW
BST
U1
LT3697EMSE
OPEN
X5
RLIM
VC
RCBL
SYNC
EN
VIN
VIN
VSYS
E10
VSYS
R1
100k
0603
GND
17
FLT
3
C3
1µF
16V
L1
0805 10uH
R14
OPT
R21
2
1206
R24
2
1206
Q1
ZXMN3A14F
R5
R23
18
18
2512 2512
R18
49.9k
0603
R16
43.2k
0603
R17
49.9k
0603
R15
43.2k
0603
10k
OPEN DX2
3
2
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
OPEN
2
X3
DATE:
N/A
SIZE
GND
VOUT
5.xV / 2.4A
C_GND
VCABLE
5V / 2.4A
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
USB
1
2 1
3 2
4 3
4
J3
E9
E7
E5
C11 E3
1µF
25V
0805
VCABLE
C12
1µF
25V
0805
E15
VCABLE
1
LT3697EMSE
DEMO CIRCUIT 1893A
SHEET
1
OF
USB 35V, 2.5A BUCK
WITH CABLE DROP COMPENSATION
1
3
REV.
LTC Confidential-For Customer Use Only
TECHNOLOGY Fax: (408)434-0507
DATA-
DATA+
1
VSYS
C10
5.xV / 0.1A
0.1µF E13
25V
0603
GND
E12
0.3 2W
0830
C-GND
R13
OPT 1206 E17
R4
Monday, September 08, 2014
IC NO.
TITLE: SCHEMATIC
1
SHORT
GND
E14
VCABLE
SUNCON
16HVP120M
120uF
16V
+ C26
X4
OPEN SET
3
1
0.022
1206
E16
VOUT
X1
OPEN D+
3
1
10nF
R9
C13
C9
OPT
10V
1206
CUSTOMER NOTICE
C25
OPT
1210
R3
VSYS
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.
NRS8040T100MJGJV C4
47µF
10V
D2
MBRA340T3G 1210
VCABLE
12
13
10
11
16
15
14
D1
CMDSH-3
2
2
4
1
V+
GND
2
3
2
3
1
DIV
4
2
2
3
1
5
A
B
C
D
DEMO MANUAL DC1893A
SCHEMATIC DIAGRAM
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DEMO MANUAL DC1893A
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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8
Linear Technology Corporation
LT 1014 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2014
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