LTM4600
10A High Efficiency
DC/DC µModule
FEATURES
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DESCRIPTION
The LTM
®
4600 is a complete 10A, DC/DC step down power
supply. Included in the package are the switching control-
ler, power FETs, inductor, and all support components.
Operating over an input voltage range of 4.5V to 20V, the
LTM4600 supports an output voltage range of 0.6V to 5V,
set by a single resistor. This high efficiency design delivers
10A continuous current (14A peak), needing no heat sinks
or airflow to meet power specifications. Only bulk input
and output capacitors are needed to finish the design.
The low profile package (2.8mm) enables utilization of
unused space on the bottom of PC boards for high density
point of load regulation. High switching frequency and an
adaptive on-time current mode architecture enables a very
fast transient response to line and load changes without
sacrificing stability. Fault protection features include
integrated overvoltage and short circuit protection with
a defeatable shutdown timer. A built-in soft-start timer is
adjustable with a small capacitor.
The LTM4600 is packaged in a thermally enhanced, compact
(15mm
×
15mm) and low profile (2.8mm) over-molded
Land Grid Array (LGA) package suitable for automated
assembly by standard surface mount equipment. The
LTM4600 is Pb-free and RoHS compliant.
Complete Switch Mode Power Supply
Wide Input Voltage Range: 4.5V to 20V
10A DC, 14A Peak Output Current
Parallel Two μModule™ DC/DC Converters for 20A
Output Current
0.6V to 5V Output Voltage
1.5% Output Voltage Regulation
Ultrafast Transient Response
Current Mode Control
Pb-Free (e4) RoHS Compliant Package with Gold-
Pad Finish
Up to 92% Efficiency
Programmable Soft-Start
Output Overvoltage Protection
Optional Short-Circuit Shutdown Timer
Small Footprint, Low Profile (15mm × 15mm ×
2.8mm) Surface Mount LGA Package
APPLICATIONS
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Telecom and Networking Equipment
Servers
Industrial Equipment
Point of Load Regulation
L,
LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
μModule is a trademark of Linear Technology Corporation. All other trademarks are the property
of their respective owners. Protected by U.S. Patents including 5481178, 6100678, 6580258,
5847554, 6304066.
TYPICAL APPLICATION
100
Efficiency vs Load Current
with 12V
IN
(FCB = 0)
90
80
EFFICIENCY (%)
70
60
50
40
4600 TA01a
10A μModule Power Supply with 4.5V to 20V Input
V
IN
4.5V TO 20V
V
IN
C
IN
V
OUT
LTM4600
V
OSET
PGND SGND
C
OUT
V
OUT
1.5V
10A
66.5k
30
20
0
2
6
LOAD CURRENT (A)
4
1.2V
OUT
1.5V
OUT
2.5V
OUT
3.3V
OUT
8
10
4600 TA01b
4600fc
1
LTM4600
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
f
ADJ
SV
IN
EXTV
CC
V
OSET
COMP
SGND
RUN/SS
FCB
PGOOD
PGND
TOP VIEW
FCB, EXTV
CC
, PGOOD, RUN/SS, V
OUT
.......... –0.3V to 6V
V
IN
, SV
IN
, f
ADJ
............................................ –0.3V to 20V
V
OSET
, COMP ............................................. –0.3V to 2.7V
Operating Temperature Range (Note 2).... –40°C to 85°C
Junction Temperature ........................................... 125°C
Storage Temperature Range................... –55°C to 125°C
V
IN
V
OUT
LGA PACKAGE
104-LEAD (15mm
×
15mm
×
2.8mm)
T
JMAX
= 125°C,
θ
JA
= 15°C/W,
θ
JC
= 6°C/W,
θ
JA
DERIVED FROM 95mm
×
76mm PCB WITH 4 LAYERS
WEIGHT = 1.7g
ORDER INFORMATION
LEAD FREE FINISH
LTM4600EV#PBF
LTM4600IV#PBF
PART MARKING
LTM4600EV
LTM4600IV
PACKAGE DESCRIPTION
104-Lead (15mm
×
15mm
×
2.8mm) LGA
104-Lead (15mm
×
15mm
×
2.8mm) LGA
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
This product is only offered in trays. For more information go to:
http://www.linear.com/packaging/
The
l
denotes the specifications which apply over the –40°C to 85°C
temperature range, otherwise specifications are at T
A
= 25°C, V
IN
= 12V. External C
IN
= 120μF C
OUT
= 200μF/Ceramic per typical
,
application (front page) configuration.
SYMBOL
V
IN(DC)
V
OUT(DC)
PARAMETER
Input DC Voltage
Output Voltage
FCB = 0V
V
IN
= 5V or 12V, V
OUT
= 1.5V, I
OUT
= 0A
CONDITIONS
l
ELECTRICAL CHARACTERISTICS
MIN
4.5
1.478
1.470
TYP
MAX
20
UNITS
V
V
V
V
A
A
mA
mA
mA
mA
μA
4600fc
l
1.50
1.50
3.4
0.6
0.7
1.2
42
1.0
52
35
1.522
1.530
4
Input Specifications
V
IN(UVLO)
I
INRUSH(VIN)
Under Voltage Lockout Threshold
Input Inrush Current at Startup
I
OUT
= 0A
I
OUT
= 0A. V
OUT
= 1.5V, FCB = 0
V
IN
= 5V
V
IN
= 12V
I
OUT
= 0A, EXTV
CC
Open
V
IN
= 12V, V
OUT
= 1.5V, FCB = 5V
V
IN
= 12V, V
OUT
= 1.5V, FCB = 0V
V
IN
= 5V, V
OUT
= 1.5V, FCB = 5V
V
IN
= 5V, V
OUT
= 1.5V, FCB = 0V
Shutdown, RUN = 0.8V, V
IN
= 12V
I
Q(VIN)
Input Supply Bias Current
75
2
LTM4600
ELECTRICAL CHARACTERISTICS
SYMBOL
I
S(VIN)
PARAMETER
Input Supply Current
The
l
denotes the specifications which apply over the –40°C to 85°C
temperature range, otherwise specifications are at T
A
= 25°C, V
IN
= 12V. Per typical application (front page) configuration.
CONDITIONS
V
IN
= 12V, V
OUT
= 1.5V, I
OUT
= 10A
V
IN
= 12V, V
OUT
= 3.3V, I
OUT
= 10A
V
IN
= 5V, V
OUT
= 1.5V, I
OUT
= 10A
0
MIN
TYP
1.52
3.13
3.64
10
MAX
UNITS
A
A
A
A
Output Specifications
I
OUTDC
Output Continuous Current Range
V
IN
= 12V, V
OUT
= 1.5V
(See Output Current Derating Curves for
Different V
IN
, V
OUT
and T
A
)
Line Regulation Accuracy
Load Regulation Accuracy
V
OUT
= 1.5V, I
OUT
= 0A, FCB = 0V,
V
IN
= 4.5V to 20V
V
OUT
= 1.5V, I
OUT
= 0A to 10A, FCB = 0V
V
IN
= 5V
V
IN
= 12V (Notes 3, 4)
V
IN
= 12V, V
OUT
= 1.5V, I
OUT
= 0A, FCB = 0V
V
OUT
= 1.5V, I
OUT
= 5A, FCB = 0V
V
OUT
= 1.5V, I
OUT
= 1A
V
IN
= 12V
V
IN
= 5V
V
OUT
= 1.5V, Load Step: 0A/μs to 5A/μs
C
OUT
= 3 • 22μF 6.3V, 470μF 4V POSCAP
,
See Table 2
Load: 10% to 90% to 10% of Full Load
Output Voltage in Foldback
V
IN
= 12V, V
OUT
= 1.5V
V
IN
= 5V, V
OUT
= 1.5V
I
OUT
= 0A, V
OUT
= 1.5V
l
l
ΔV
OUT(LINE)
V
OUT
ΔV
OUT(LOAD)
V
OUT
V
OUT(AC)
fs
t
START
0.15
0.3
%
l
±1
±1.5
10
850
0.5
0.7
36
15
%
%
mV
P-P
kHz
ms
ms
mV
Output Ripple Voltage
Output Ripple Voltage Frequency
Turn-On Time
ΔV
OUTLS
Voltage Drop for Dynamic Load Step
t
SETTLE
I
OUTPK
Settling Time for Dynamic Load Step
Output Current Limit
25
14
14
0.591
0.594
0.8
–0.5
0.8
0.6
0.6
1.5
–1.2
1.8
100
16
100
0.57
0.6
–1
7.5
–7.5
10
–10
2
0.15
0.4
0.63
–2
12.5
–12.5
0.609
0.606
2
–3
3
μs
A
A
V
V
V
μA
μA
mV
mA
kΩ
V
μA
%
%
%
V
Control Stage
V
OSET
V
RUN/SS
I
RUN(C)/SS
I
RUN(D)/SS
V
IN
– SV
IN
I
EXTVCC
R
FBHI
V
FCB
I
FCB
PGOOD Output
ΔV
OSETH
ΔV
OSETL
ΔV
OSET(HYS)
V
PGL
PGOOD Upper Threshold
PGOOD Lower Threshold
PGOOD Hysteresis
PGOOD Low Voltage
V
OSET
Rising
V
OSET
Falling
V
OSET
Returning
I
PGOOD
= 5mA
Current into EXTV
CC
Pin
Resistor Between V
OUT
and V
OSET
Pins
Forced Continuous Threshold
Forced Continuous Pin Current
V
FCB
= 0.6V
Voltage at V
OSET
Pin
RUN ON/OFF Threshold
Soft-Start Charging Current
Soft-Start Discharging Current
V
RUN/SS
= 0V
V
RUN/SS
= 4V
EXTV
CC
= 0V, FCB = 0V
EXTV
CC
= 5V, FCB = 0V, V
OUT
= 1.5V,
I
OUT
= 0A
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The LTM4600E is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTM4600I is guaranteed over the
–40°C to 85°C temperature range.
Note 3:
Test assumes current derating versus temperature.
Note 4:
Guaranteed by correlation.
4600fc
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LTM4600
TYPICAL PERFORMANCE CHARACTERISTICS
Efficiency vs Load Current
with 5V
IN
(FCB = 0)
100
90
80
EFFICIENCY (%)
EFFICIENCY (%)
70
60
50
40
30
0
2
6
4
LOAD CURRENT (A)
100
90
80
70
60
50
40
30
0.6V
OUT
1.2V
OUT
1.5V
OUT
2.5V
OUT
3.3V
OUT
0
2
6
LOAD CURRENT (A)
4
8
10
4600 G02
(See Figure 18 for all curves)
Efficiency vs Load Current
with 18V
IN
(FCB = 0)
100
90
80
70
60
50
40
30
0
2
4
6
LOAD CURRENT (A)
8
10
4600 G03
Efficiency vs Load Current
with 12V
IN
(FCB = 0)
EFFICIENCY (%)
0.6V
OUT
1.2V
OUT
1.5V
OUT
2.5V
OUT
8
10
4600 G01
1.5V
OUT
1.8V
OUT
2.5V
OUT
3.3V
OUT
Efficiency vs Load Current
with Different FCB Settings
90
80
70
EFFICIENCY (%)
60
FCB = GND
50
40
30
20
0.1
V
IN
= 12V
V
OUT
= 1.5V
1
LOAD CURRENT (A)
10
4600 G04
1.2V Transient Response
1.5V Transient Response
FCB > 0.7V
V
OUT
= 50mV/DIV
I
OUT
= 5A/DIV
25μs/DIV
1.2V AT 5A/μs LOAD STEP
C
OUT
= 3 • 22μF 6.3V CERAMICS
470μF 4V SANYO POSCAP
C3 = 100pF
4600 G05
25μs/DIV
1.5V AT 5A/μs LOAD STEP
C
OUT
= 3 • 22μF 6.3V CERAMICS
470μF 4V SANYO POSCAP
C3 = 100pF
4600 G06
1.8V Transient Response
2.5V Transient Response
3.3V Transient Response
25μs/DIV
1.8V AT 5A/μs LOAD STEP
C
OUT
= 3 • 22μF 6.3V CERAMICS
470μF 4V SANYO POSCAP
C3 = 100pF
4600 G07
25μs/DIV
2.5V AT 5A/μs LOAD STEP
C
OUT
= 3 • 22μF 6.3V CERAMICS
470μF 4V SANYO POSCAP
C3 = 100pF
4600 G08
25μs/DIV
3.3V AT 5A/μs LOAD STEP
C
OUT
= 3 • 22μF 6.3V CERAMICS
470μF 4V SANYO POSCAP
C3 = 100pF
4600 G09
4600fc
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LTM4600
TYPICAL PERFORMANCE CHARACTERISTICS
(See Figure 18 for all curves)
Start-Up, I
OUT
= 0A
V
OUT
(0.5V/DIV)
I
IN
(0.5A/DIV)
Start-Up, I
OUT
= 10A
(Resistive Load)
V
OUT
(0.5V/DIV)
I
IN
(0.5A/DIV)
Short-Circuit Protection,
I
OUT
= 0A
V
OUT
(0.5V/DIV)
I
IN
(0.2A/DIV)
200μs/DIV
V
IN
= 12V
V
OUT
= 1.5V
C
OUT
= 200μF
NO EXTERNAL SOFT-START CAPACITOR
4600 G10
200μs/DIV
V
IN
= 12V
V
OUT
= 1.5V
C
OUT
= 200μF
NO EXTERNAL SOFT-START CAPACITOR
4600 G11
20μs/DIV
V
IN
= 12V
V
OUT
= 1.5V
C
OUT
= 2× 200μF/X5R
NO EXTERNAL SOFT-START CAPACITOR
4600 G12
Short-Circuit Protection,
I
OUT
= 10A
5.5
5.0
V
OUT
(0.5V/DIV)
I
IN
(0.5A/DIV)
4.5
4.0
3.5
V
OUT
(V)
3.0
2.5
2.0
1.5
1.0
0.5
0
V
IN
to V
OUT
Step-Down Ratio
f
ADJ
= OPEN
5V
0.00
–0.05
–0.10
LOAD REGULATION %
3.3V
2.5V
1.8V
1.5V
1.2V
0.6V
0
5
10
V
IN
(V)
SEE FREQUENCY ADJUSTMENT DISCUSSION
FOR 12V
IN
TO 5V
OUT
AND 5V
IN
TO 3.3V
OUT
CONVERSION
4600 G14
12V Input Load Regulation vs
Temperature
–0.15
–0.20
–0.25
–0.30
100°C
–0.35
–0.40
–45°C
25°C
20μs/DIV
V
IN
= 12V
V
OUT
= 1.5V
C
OUT
= 2× 200μF/X5R
NO EXTERNAL SOFT-START CAPACITOR
4600 G13
15
20
–0.45
0
5
LOAD CURRENT
10
4600 G15
4600fc
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