QUICK START GUIDE FOR DEMONSTRATION CIRCUIT DC667
4A MONOLITHIC SYNCHRONOUS STEP-DOWN REGULATOR WITH TRACKING
LTC3416
DESCRIPTION
Demonstration circuit 667 is a high efficiency, high
frequency buck converter, incorporating the LTC3416
monolithic synchronous regulator. DC667 operates in
forced continuous operation and provides tracking of
another power supply rail. It operates from an input
voltage range of 2.25V to 5.5V and provides a regu-
lated output voltage from 0.8V to 5V. DC667 can de-
liver high power – up to 4A of output current - in a
relatively small circuit, thanks to 67mohm high cur-
rent power switches in the LTC3416. The LTC3416
also incorporates OPTI-LOOP compensation, so that
the DC667 can be optimized to provide fast transient
response over a wide range of line and load condi-
tions. All these features make the DC667 perfectly
suited for battery powered, hand-held applications.
Design files for this circuit board are available. Call
the LTC factory.
QUICK START PROCEDURE
Demonstration circuit DC667 is easy to set up to
evaluate the performance of the LTC3416EFE. Refer
to Figure 1 for proper measurement equipment setup
and follow the procedure below:
NOTE:
When measuring the input or output voltage
NOTE:
Make sure that the input voltage VIN does not
exceed 5.5V.
6.
Check for the output voltages VOUT = 2.5V
ripple, care must be taken to avoid a long ground lead
on the oscilloscope probe. Measure the input or out-
put voltage ripple by touching the probe tip directly
across the VIN or VOUT and GND terminals. See Fig-
ure 2 for proper scope probe technique.
1.
Place jumper JP1 in the ON position.
2.
Connect Jumper JP4 for 2.5V Output Voltage.
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 voltages are established,
adjust the loads within 4A range and observe the
output voltage regulation, ripple voltage, efficiency
and other parameters.
8.
To test tracking functions, place JP2 to ON posi-
Leave JP3, JP5 and JP6 unconnected.
3.
With power off, connect the input power supply
tion, and connect TRACK terminal to 1.25V Voltage
supply (through a voltage divider, the voltage on
Track pin of the IC is about 550mV), the output
voltage will be regulated at 1.75V.
9.
Connect TRACK terminal to GND, the VOUT should
VIN to VIN and GND.
4.
Connect TRACK terminal to VIN (JP2 to Off posi-
be less than 200mV in normal operation.
10.
To test 1.8V output voltage, connect JP3 and leave
tion), tracking function is disabled.
5.
Apply input power at the VIN slowly, by increasing
VIN from 0V to 5.5V.
JP4, JP5 and JP6 unconnected. Repeat the proce-
dure 3 to 7. Follow the similar procedure for other
output voltage tests.
1
5
4
3
2
1
U1
LTC3416EFE
D
TP1
VIN
2.5-5.5V
TP2
GND
7
CIN1
100uF
6.3V
1210
CIN2
100uF
6.3V
1210
CIN3
100uF
6.3V
7343
OPT
CIN4
1210
OPT
RSS
2.2M
6
14
15
16
RPG
100K
17
JP1
VOUT
OFF
ON
4
3
PVIN
NC
PVIN
NC
SVIN
SW 8
SW 9
SW 12
SW 13
VISHAY
IHLP-2525CZ-47
L1
0.47uH
COUT1
100uF
6.3V
1210
COUT2
100uF
6.3V
1210
CFF
22pF
R1
200K
1%
RFB1
255K 1%
RFB2
432K 1%
RFB3
634K 1%
RFB4
OPT
1.8V
JP3
2.5V
JP4
3.3V
JP5
COUT3
100uF
6.3V
7343
OPT
TP3
VOUT
4A MAX
D
TP4
GND
TP5
PGOOD
PGOOD
RUN/SS
TRACK
SGND
PGND
PGND
PGND
VFB 19
ITH 18
RT 2
PGND
RITH
7.5K
1%
RT
294K
1%
CITH
820pF
C1
47pF
C
10
11
JP2
TRACK
ON
OFF
R3
255K
1%
20
5
1
TRACK
TP6
C
USER SELECT
R2
200K
1%
JP6
B
B
BOARD LAYOUT
CITH
RT
R1
R2
C1
NOTES: UNLESS OTHERWISE SPECIFIED
1. ALL RESISTORS ARE IN OHMS, 0402.
2. ALL CAPACITORS ARE IN MICROFARAD, 0402.
3. INSTALL SHUNTS ON JP1 AND JP2 PIN 2 AND 3, JP4 PIN 1 AND 2.
RITH
RSS
CIN1
U1
RPG
COUT1
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
CIRUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
CONTRACT NO.
APPROVALS
DRAWN:
CHECKED:
APPROVED:
ENGINEER:
RAYMOND Z.
SIZE
DESIGNER:
KIM T.
CIN2
L1
TECHNOLOGY
TITLE: SCHEMATIC
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
A
A
4A, MONOLITHIC, SYNCHRONOUS STEP-DOWN
REGULATOR WITH TRACKING
DWG NO.
A
DC667A-1 * LTC3416EFE
SHEET 1
1
REV
A
OF 1
DATE:
Friday, January 09, 2004
2
5
4
3
Linear Technology Corporation
LTC3416EFE
4A, MONOLITHIC, SYNCHRONOUS STEP-DOWN REGULATOR WITH TRACKING
ENG: RAYMOND ZHENG (23-30)
BILL OF MATERIALS
DC667A-1
6/20/2005
Item
Qty Reference
Part Description
Manufacture / Part #
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
1
4
0
0
1
1
0
2
4
3
1
2
1
1
0
1
1
1
1
2
0
6
1
4
4
1
CFF
CIN1,CIN2, COUT1,COUT2
CIN3,COUT3 (OPT)
CIN4 (OPT)
CITH
C1
C2 (OPT)
JP1,JP2
JP3,JP4,JP5,JP6
SHUNTS FOR JP1,JP2,JP4
L1
RFB1,R3
RFB2
RFB3
RFB4,RFB5
RITH
RPG
RSS
RT
R1,R2
R4 (OPT)
TP1-TP6
U1
Cap., NPO 22pF 25V 10%
Cap., X5R 100uF 6.3V 20%,1210
Cap., X5R 100uF 6.3V 20%,7343-1812
Cap., X5R,1210
Cap., X7R 820pF 25V 20%
Cap., NPO 47pF 25V 10%
Cap., NPO 39pF 25V 10%
Headers, 3 Pins 2mm Ctrs.
Jumper, 2pins 2mm Ctrs.
Shunt, 2 Pins 2mm Ctrs.
Inductor, 0.47uH
Res., Chip 255K 1/16W 1%
Res., Chip 432K 1/16W 1%
Res., Chip 634K 1/16W 1%
Jumper, Chip 0 1/16W 5%
Res., Chip 7.5K 1/16W 1%
Res., Chip 100K 0.06W 5%
Res., Chip 2.2M 1/16W 5%
Res., Chip 294K 0.06W 1%
Res., Chip 200K 1/16W 1%
Res., Chip 1K 0.06W 5%
Turret, Testpoint
I.C., Step-Down Reg., TSSOP20FE
SCREW, #4-40, 1/4"
STANDOFF, #4-40 1/4"
AVX 04023A220KAT2A
TDK C3225X5R0J107M
TDK C3225X5R0J107M
or POSCAP 6TPE150M
OPT
AVX 04023C821MAT2A
AVX 04023A470KAT2A
AVX 04023A390KAT2A
CommConn Con. Inc. 2802S-03G2
CommConn Con. Inc. 2802s-02g2
CommConn Con. Inc. CCIJ2MM-138G
VISHAY IHLP-2525CZ-47
AAC CR05-2553FM
AAC CR05-4323FM
AAC CR05-6343FM
OPT
AAC CR05-7501FM
AAC CR05-104JM
AAC CR05-225JM
AAC CR05-2943FM
AAC CR05-2003FM
AAC CR05-102JM
Mill Max 2501-2
Linear Tech. Corp. LTC3416EFE
ANY
MICRO PLASTICS 14HTSP101
STENCIL FOR TOP SIDE
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