DC1632A - Demo Manual

DEMO MANUAL DC1632A
LTC3839EUH
Fast Transient
Step-Down DC/DC Converter
DESCRIPTION
Demonstration circuit 1632A is a single output 1.5V/40A
dual phase synchronous buck converter operating with
a switching frequency of 300kHz over an input voltage
range of 4.5V to 14V. The controlled on-time valley current
mode architecture of the LTC3839 allows for a fast load
step response (see Figure 4). The load step response can
be tested with the on-board load step circuit and a bench
pulse generator.
Other features of the board include remote sensing, selectable light load operating modes of forced continuous
mode (FCM) and discontinuous mode (DCM), a PLLIN
pin for synchronizing to an external clock, a CLKOUT
pin, an EXTVCC pin to reduce losses in the controller, and
PERFORMANCE SUMMARY
PARAMETER
RUN and TRACK/SS pins. Up to 12-phase operation can
be achieved by daisy-chaining the CLKOUT and PLLIN
signals of multiple boards and programming the relative
phase with the PHASMD jumper.
The demo board uses a high density, two sided drop-in
layout. The entire converter, excluding the bulk output and
input capacitors, fits within a compact 1.6˝ × 1.2˝ area
on the board. The package style for the LTC3839EUH is a
32-lead 5mm × 5mm QFN with an exposed ground pad.
Design files for this circuit board are available at
http://www.linear.com/demo
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.
(TA = 25°C)
CONDITIONS
VALUE
Minimum Input Voltage
4.5V
Maximum Input Voltage
14V
Output Voltage VOUT
IOUT = 0A to 40A, VIN = 4.5V to 14V
1.5V ± 2%
VOUT Maximum Output Current, IOUT
VIN = 4.5V to 14V, VOUT = 1.5V
40A
Nominal Switching Frequency
Efficiency (see Figures 2 and 3)
300kHz
VOUT = 1.5V, IOUT = 40A, VIN = 12V
90.7% Typical
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DEMO MANUAL DC1632A
QUICK START PROCEDURE
Demonstration circuit 1632A is easy to set up to evaluate the performance of the LTC3839EUH. Please refer to
Figure 1 for proper measurement equipment setup and
follow the procedure below.
1) With power off, connect the input supply, load and meters as shown in Figure 1. Preset the load to 0A and VIN
supply to 0V. Place jumpers in the following positions:
JP1
JP3
RUN
MODE
ON
FCM
2) Adjust the input voltage to be between 4.5V and 14V.
VOUT should be 1.5V ±2%.
3) Next, apply 40A load and re-check VOUT.
4) Once the DC regulation is confirmed, observe the output
voltage ripple, load step response, efficiency and other
parameters.
Note 1. Use the BNC connector labeled VOUT to measure
the output voltage ripple.
Load Step Testing (Optional)
Demonstration circuit 1632A provides a simple load step
circuit consisting of a MOSFET and sense resistor for each
rail. To apply a load step, follow the steps below.
1) Pre-set the amplitude of a pulse generator to 0.0V and
the duty cycle to 5% or less.
2) Connect the scope to the VOUT BNC connectors for
the rail under test with a coax cable. To monitor the
load step current, connect the scope probe across the
ISTEP± pins.
3) Connect the output of the pulse generator to the PULSE
GEN pin and connect the return to the GND pin.
4) With the converter running, slowly increase the amplitude of the pulse generator output to provide the desired
load step pulse height. The scaling for the LOAD STEP
signal is 5mV/Amp.
Note 2. Do not apply the load from the VO_SNS+ pin to
the VO_SNS– pin. This may damage the converter. These
pins are only intended to monitor the voltage across the
bulk output capacitors at COUT1-4.
VIN
SUPPLY
LIN
IOUT
+
+
–
+
VOUT
LOAD
VIN
–
–
+
–
VOUT*
* MONITOR THE VOLTAGE ACROSS COUT5 FOR
ACCURATE EFFICIENCY MEASUREMENTS.
Figure 1. Proper Measurement Equipment Setup
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DEMO MANUAL DC1632A
QUICK START PROCEDURE
LTC3839 1.5V/40A Converter FCM, fSW = 300kHz
95
EFFICIENCY (%)
VIN = 5V
VIN = 12V
90
85
Qtop = Infineon BSC050NE2LS
Qbottom = Infineon BSC010NE2LS
L = Coiltronics FP1308R3-R44-R
(0.44μH, DCR = 0.18m Ω±20%)
RSENSE = 2mΩ
80
75
0
5
10
15
20
25
30
35
40
45
LOAD CURRENT (A)
Figure 2. Efficiency Curves for the DC1632A in FCM
LTC3839 1.5V/40A Converter FCM & DCM, VIN = 12V, fSW = 300kHz
DCM
FCM
EFFICIENCY (%)
100
90
80
70
60
50
40
30
20
10
0
0.01
Qtop = Infineon BSC050NE2LS
Qbottom = Infineon BSC010NE2LS
L = Coiltronics FP1308R3-R44-R
(0.44μH, DCR = 0.18m Ω±20%)
RSENSE = 2mΩ
0.10
1.00
10.00
100.00
LOAD CURRENT (A)
Figure 3. Efficiency Curves for the DC1632A in FCM and DCM
20μsec/DIV
1.5V(AC)
50mV/DIV
106mVP-P
40A
LOAD STEP
10A/DIV
20A
Figure 4. Load Step Response of the DC1632A at VIN = 12V. COUT = 4× Sanyo
2R5TPE330M9 || 2× 100μF X5R 6.3V 1206, L1, 2 = 0.44μH, fSW=300kHz
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DEMO MANUAL DC1632A
PARTS LIST
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
CAP, X5R 1μF 16V 10% 0603
AVX 0603YD105KAT2A
Required Circuit Components
1
2
C13, C5
2
3
C2, C7, C12
CAP, X5R 0.1μF 25V 10% 0603
AVX 06033C104KAT2A
3
2
C3, C11
CAP, X7R 1000pF 16V 0603
AVX 0603YC102KAT2A
4
1
C4
CAP, X5R 4.7μF 16V 10% 0805
AVX 0805YD475KAT2A
5
1
C6
CAP, NPO 68pF 25V 10% 0603
AVX 06033A680KAT2A
6
1
C8
CAP, X7R 470pF 16V 5% 0603
AVX 0603YC471JAT2A
7
1
C9
CAP, X5R 0.01μF 25V 10% 0603
AVX 06033C103KAT2A
8
1
CIN1
CAP, 180μF 16V
SANYO 16SVP180MX
9
2
CIN3, CIN4
CAP, X5R 22μF 16V 1210
MURATA GRM32ER61C226KE20L
10
4
COUT1, COUT2, COUT3, COUT4 CAP, 330μF 2.5V SIZE 7343
SANYO 2R5TPE330M9
11
2
COUT6, COUT5
CAP, X5R 100μF 6.3V 1206
MURATA GRM31CR60J107ME 39L
12
2
D1,D2
DIODE, SCHOTTKY SOD-323
CENTRAL SEMI CMDSH-4E TR
13
2
L1,L2
IND, 0.44μH
COILTRONICS FP1308R3-R44-R
14
2
Q1,Q3
MOSFET, N CHANNEL POWERPAK SO-8
INFINEON BSC050NE2LS
15
2
Q2,Q4
MOSFET, N CHANNEL POWERPAK SO-8
INFINEON BSC010NE2LS
16
3
R11, R29, R33
RES, CHIP 10k 1% 0603
VISHAY CRCW060310K0FKEA
17
1
R15
RES, CHIP 22.1k 1% 0603
VISHAY CRCW060322K1FKEA
18
1
R13
RES, CHIP 137k 1% 0603
VISHAY CRCW0603137KFKEA
19
2
R14, R12
RES, CHIP 2.2 1% 0603
VISHAY CRCW06032R20FKEA
20
1
R22
RES, CHIP 15k 1% 0603
VISHAY CRCW060315K0FKEA
21
6
R3, R7, R23, R28, R35, R25
RES, CHIP 0 0603
VISHAY CRCW06030000Z0EA
22
1
R32
RES, CHIP 100k 1% 0603
VISHAY CRCW0603100KFKEA
23
6
R4, R5, R17, R19, R26, R27
RES, CHIP 10 1% 0603
VISHAY CRCW060310R0FKEA
24
2
RS1, RS2
RES, CHIP 0.002 1W 1% 2512
VISHAY WSL25122L000FEA
25
1
U1
IC LTC3839EUH QFN 5mm × 5mm
LINEAR TECH. LTC3839EUH#PBF
Additional Circuit Components
1
0
CIN2
CAP, SVP-F8, OPT
2
0
CIN5, CIN6, CIN7, CIN8
CAP, 1210, OPT
3
0
C1, C10
CAP, 0603, OPT
4
0
COUT9-COUT12
CAP, SIZE 7343, OPT
5
0
Q5-Q8
POWERPAK SO-8, OPT
6
1
Q9
N-Channel MOSFET, TO-252
7
0
R1, R2, R6, R16, R18, R21,
R31, R8, R9, R10, R20, R24
RES, CHIP 0603, OPT
8
1
R33
RES, CHIP 10k 1% 0603
VISHAY CRCW060310K0FKEA
9
1
R34
RES, CHIP 0.005 1W 1% 2010
VISHAY WSL20105L000FEA
1
16
E1-E16
TESTPOINT, TURRET .095"
MILL-MAX 2501-2-00-80-00-00-07-0
2
1
JP1
2mm SINGLE ROW HEADER 3 PIN
SAMTEC TMM-103-02-L-S
3
2
JP3, JP2
2mm SINGLE ROW HEADER 4 PIN
SAMTEC TMM-104-02-L-S
4
6
E17-E22
JACK, BANANA
KEYSTONE 575-4
5
1
J1
CONN, BNC, 5PINS
CONNEX 112404
6
4
(STAND-OFF)
STAND-OFF, NYLON 0.25"
KEYSTONE 8831 (SNAP ON)
VISHAY SUD50N03-12P-E3
Hardware
dc1632af
4
A
B
C
D
60 DEG
90 DEG
EXTVCC
TRK/SS
3
2
R28 0
C13
1uF
EXTVCC
R11
10K
R25
0
R16
OPT
R31
OPT
C1
OPT
OPT
R18
5
2. INSTALL SHUNTS ON JUMPERS AS SHOWN.
1. ALL RESISTORS ARE IN OHMS, 0603.
ALL CAPACITORS ARE IN MICROFARADS, 0603.
NOTES: UNLESS OTHERWISE SPECIFIED
PGOOD
E10
E7
E6
E5
E4
DCM
SYNC
FCM
E12
CLKOUT
MODE
JP3
INTVCC
3
2
R1
OPT
R2
OPT
VIN
INTVCC
PHASMD
JP2
RUN
JP1
2
INTVCC
120 DEG
PLLIN
GND
OFF
ON
3
1
5
C9 0.01uF
8
7
6
5
4
VOUT
VOUTSENSE+
TRACK/SS
ITH
RT
SGND
CLKOUT
MODE/PLLIN
PHASEMD
R6
OPT
ISTEP+
ISTEPLOAD STEP
5mV / A
5% DUTY CYCLE MAX
R29
10K
R22
15K
C8 470pF
C10
OPT
R15 22.1K
C6 68pF
R13 137K
FSW = 300kHz
3
2
1
U1
LTC3839EUH
R3
0
INTVCC
S2+
E16
E15
R4
10
C3
1nF
R5
10
S2-
S1-
R32
100K
R33
10K
4
BG1
DRVCC1
VIN
PGND
INTVCC
EXTVCC
DRVCC2
BG2
E14
E13
GND
PULSE
GEN
17
18
19
20
21
C4
4.7uF
16V
0805
VOUT
3
OPT
7343-D15T
COUT9
OPT
7343-D15T
+COUT11
+
4
COUT12
OPT
7343-D15T
+
Q1
OPT
7343-D15T
+COUT10
4
4
4
INFINEON BSC050NE2LS
4
INFINEON BSC010NE2LS
Q2
4
R14 2.2
OPTIONAL COUT
C7
0.1uF
C5
1uF
INFINEON BSC010NE2LS
Q4
23
EXTVCC
22
4
Q3
INFINEON BSC050NE2LS
4
R12
2.2
INTVCC
3
24
CMDSH-3
CMDSH-3
D2
INTVCC
D1
Q9
SUD50N03-12P
1
R34
0.005
2010
VOUT
0.1uF
C12 0.1uF
R23
0
0
R7
C2
LOAD STEP CIRCUIT
1
R35
0
GND
R26 R27
10
10
C11
1nF
SGND
S1+
J1
4
29
SGND
E1
28
RUN
1
4
1
4
32
VRNG
VOUTSENSE-
9
30
SENSE2+
SENSE1+
31
SENSE2SENSE111
DTR
12
27
BOOST2
BOOST1
14
PGOOD
13
3
10
5
4
3
2
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.
2
25
TG2
26
SW2
TG1
15
SW1
16
5
6
7
8
1
2
3
5
6
7
8
1
2
3
PGND
33
5
6
7
8
1
2
3
5
6
7
8
1
2
3
5
6
7
8
1
2
3
CIN4
22uF
16V
1210
0.44uH
L2
R8 OPT
CIN6
OPT
1210
CIN3
22uF
16V
1210
0.44uH
L1
R20 OPT
CIN5
OPT
1210
S1-
R24
OPT
R21
OPT
S1+
S2-
R10
OPT
R9
OPT
S2+
2
0.002
2512
RS1
0.002
2512
RS2
2
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
R17
10
CIN8
1210
OPT
HZ
SCALE = NONE
MIKE S.
VIN-
GND
TECHNOLOGY
E11
E9
E8
MIKE S.
APPROVED
DATE
11-8-11
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
GND
VO_SNS-
VO_SNS+
E22 GND
330uF
2.5V
7343-D15T E21
VOUT
E20 1.5V / 40A
E19
E3
VIN+
VIN
4.5V - 14V
E18
E17
E2
PRODUCTION
LTC3839EUH
1
DEMO CIRCUIT 1632A
Tuesday, January 10, 2012
IC NO.
SHEET 1
OF 1
2
REV.
FAST TRANSIENT STEP-DOWN DC/DC CONVERTER
DATE:
N/A
SIZE
1
DESCRIPTION
REVISION HISTORY
+COUT1
VOUT
330uF
2.5V
7343-D15T
+COUT2
180uF
16V
+CIN1
TITLE: SCHEMATIC
R19
10
VIN
2
REV
OPT
SANYO-F8
+CIN2
__
ECO
330uF
2.5V
7343-D15T
CIN7
1210
OPT
+COUT3
APPROVALS
COUT5
100uF
6.3V
1206
330uF
2.5V
7343-D15T
+COUT4
COUT6
100uF
6.3V
1206
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
CUSTOMER NOTICE
OPTIONAL DCR
SENSE FILTER /
DIVIDER FOR
PHASE 1
Q6
OPT
Q5
OPT
OPTIONAL DCR
SENSE FILTER /
DIVIDER FOR
PHASE 2
Q8
OPT
Q7
OPT
5
6
7
8
1
2
3
5
6
7
8
1
2
3
5
6
7
8
1
2
3
RUN
A
B
C
D
DEMO MANUAL DC1632A
SCHEMATIC DIAGRAM
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DEMO MANUAL DC1632A
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
dc1632af
6
Linear Technology Corporation
LT 0212 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507 ● www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2012