switch mode DC/DC power supply. Included in the pack-
age are the switching controller, power FETs, inductor and
compensation components. Operating over an input voltage
range from 4.5V to 20V, the LTM4627 supports an output
voltage range of 0.6V to 5V, set by a single external resistor.
Only a few input and output capacitors are needed.
Current mode operation allows precision current sharing
of up to four LTM4627 regulators to obtain 60A output.
High switching frequency and a current mode architecture
enable a very fast transient response to line and load
changes without sacrificing stability. The device supports
frequency synchronization, multiphase/current sharing
operation, Burst Mode operation and output voltage track-
ing for supply rail sequencing.
The LTM4627 is offered in a thermally enhanced 15mm
×
15mm
×
4.32mm LGA package. The LTM4627 is PB-free
and RoHS compliant.
L,
LT, LTC, LTM, Linear Technology, the Linear logo, Burst Mode and μModule are registered
trademarks of Linear Technology Corporation. PolyPhase is a registered trademark of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 5481178, 5847554, 6580258, 6304066, 6476589,
6774611, 6677210.
Complete 15A Switch Mode Power Supply
Wide Input Voltage Range: 4.5V to 20V
0.6V to 5V Output Range
±1.5% Total DC Output Error (–40°C to 125°C)
Differential Remote Sense Amplifier for Precision
Regulation
Current Mode Control/ Fast Transient Response
Frequency Synchronization
Parallel Current Sharing (Up to 60A)
Selectable Pulse-Skipping or Burst Mode
®
Operation
Soft-Start/Voltage Tracking
Up to 93% Efficiency (12V
IN
, 3.3V
OUT
)
Overcurrent Foldback Protection
Output Overvoltage Protection
Small Surface Mount Footprint, Low Profile
15mm
×
15mm
×
4.32mm LGA Package
APPLICATIONS
n
n
n
n
Telecom Servers and Networking Equipment
ATCA and Storage Cards
Industrial Equipment
Medical Systems
TYPICAL APPLICATION
1.2V, 15A DC/DC μModule
®
Regulator
V
IN
4.5V TO 16V
95
22μF
16V
×3
90
150pF
10k
0.1μF
V
IN
COMP
TRACK/SS
RUN
f
SET
100k
MODE_PLLIN
SGND
* SEE TABLE 4
** SEE TABLE 1
GND
LTM4627
EXTV
CC
INTV
CC
PGOOD
V
OUT
V
OUT_LCL
DIFF_OUT
V
OSNS+
V
OSNS–
VFB
R
FB
**
60.4k
4627 TA01a
Efficiency vs Load Current
85
EFFICIENCY (%)
V
OUT
1.2V
15A
100μF*
6.3V
80
75
70
65
60
55
50
0
2
4
12V
IN
, 1.2V
OUT
5V
IN
, 1.2V
OUT
6
10 12
8
LOAD CURRENT (A)
14
16
+
82pF
470μF
6.3V
4627 TA01b
4627f
1
LTM4627
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
V
IN
TOP VIEW
MODE_PLLIN
INTV
CC
TRACK/SS
4
5
6
7
8
9
10
11
V
IN
............................................................. –0.3V to 22V
INTV
CC
, V
OUT
(V
OUT
≤ 3.3V with
DIFF AMP), V
OUT_LCL
, PGOOD, EXTV
CC
....... –0.3V to 6V
MODE_PLLIN, f
SET
, TRACK/SS,
V
OSNS –
, V
OSNS+
, DIFF_OUT...................–0.3V to INTV
CC
COMP, V
FB
................................................ –0.3V to 2.7V
RUN (Note 5) ............................................... –0.3V to 5V
INTV
CC
Peak Output Current (Note 6) ..................100mA
Internal Operating Temperature Range
(Note 2).................................................. –40°C to 125°C
Storage Temperature Range .................. –55°C to 125°C
Reflow (Peak Body) Temperature .......................... 250°C
COMP
12
1
A
2
3
V
IN
B
C
D
E
F
RUN
f
SET
INTV
CC
EXTV
CC
PGOOD
V
FB
PGOOD
SGND
V
OSNS+
DIFF_OUT
V
OUT_LCL
V
OSNS–
V
OUT
LGA PACKAGE
133-LEAD (15mm 15mm
4.32mm)
GND
G
H
J
K
L
M
V
OUT
T
J(MAX)
= 125°C,
θ
JA
= 13°C/W,
θ
JCbottom
= 2.3°C/W,
θ
JCtop
= 11°C/W to 13°C/W,
θ
JA
DERIVED FROM 95mm × 76mm PCB WITH 4 LAYERS; WEIGHT = 2.6g
θ
VALUES DETERMINED PER JESD51-12
ORDER INFORMATION
LEAD FREE FINISH
LTM4627EV#PBF
LTM4627IV#PBF
TRAY
LTM4627EV#PBF
LTM4627IV#PBF
PART MARKING*
LTM4627V
LTM4627V
PACKAGE DESCRIPTION
133-Lead (15mm
×
15mm
×
4.32mm) LGA
133-Lead (15mm
×
15mm
×
4.32mm) LGA
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
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/
ELECTRICAL CHARACTERISTICS
SYMBOL
V
IN
V
OUT(DC)
PARAMETER
Input DC Voltage
Output Voltage, Total
Variation with Line and Load
CONDITIONS
The
l
denotes the specifications which apply over the full internal operating
temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, per the typical application in Figure 18.
MIN
l
TYP
1.50
MAX
20
1.523
UNITS
V
V
4.5
1.477
C
IN
= 22μF
×
3
C
OUT
= 100μF Ceramic, 470μF POSCAP
R
FB
= 40.2k, MODE_PLLIN = GND
V
IN
= 5V to 20V, I
OUT
= 0A to 15A (Note 4)
V
RUN
Rising
l
Input Specifications
V
RUN
V
RUNHYS
RUN Pin On Threshold
RUN Pin On Hysteresis
1.1
1.25
130
1.4
V
mV
4627f
2
LTM4627
ELECTRICAL CHARACTERISTICS
SYMBOL
I
Q(VIN)
PARAMETER
Input Supply Bias Current
CONDITIONS
V
IN
= 12V, V
OUT
= 1.5V, Burst Mode Operation, I
OUT
= 0.1A
V
IN
= 12V, V
OUT
= 1.5V, Pulse-Skipping Mode, I
OUT
= 0.1A
V
IN
= 12V, V
OUT
= 1.5V, Switching Continuous, I
OUT
= 0.1A
Shutdown, RUN = 0, V
IN
= 12V
V
IN
= 5V, V
OUT
= 1.5V, I
OUT
= 15A
V
IN
= 12V, V
OUT
= 1.5V, I
OUT
= 15A
V
IN
= 12V, V
OUT
= 1.5V (Note 4)
V
OUT
= 1.5V, V
IN
from 4.5V to 20V
I
OUT
= 0A
V
OUT
= 1.5V, I
OUT
= 0A to 15A, V
IN
= 12V (Note 4)
I
OUT
= 0A, C
OUT
= 100μF Ceramic, 470μF POSCAP
V
IN
= 12V, V
OUT
= 1.5V
C
OUT
= 100μF Ceramic, 470μF POSCAP
,
V
OUT
= 1.5V, I
OUT
= 0A, V
IN
= 12V
C
OUT
= 100μF Ceramic, 470μF POSCAP
,
No Load, TRACK/SS = 0.001μF V
IN
= 12V
,
Load: 0% to 50% to 0% of Full Load
C
OUT
= 100μF Ceramic, 470μF POSCAP
,
V
IN
= 12V, V
OUT
= 1.5V
Load: 0% to 50% to 0% of Full Load V
IN
= 5V,
C
OUT
= 100μF Ceramic, 470μF POSCAP
V
IN
= 12V, V
OUT
= 1.5V
V
IN
= 5V, V
OUT
= 1.5V
I
OUT
= 0A, V
OUT
= 1.5V
(Note 7)
l
l
l
l
The
l
denotes the specifications which apply over the full internal operating
temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, per the typical application in Figure 18.
MIN
TYP
17
25
54
40
5.05
2.13
0
0.02
0.2
15
20
50
60
15
0.06
0.45
MAX
UNITS
mA
mA
mA
μA
A
A
A
%/V
%
mV
P-P
mV
ms
mV
I
S(VIN)
Input Supply Current
Output Specifications
I
OUT(DC)
ΔV
OUT
(Line)
V
OUT
ΔV
OUT
(Load)
V
OUT
V
OUT(AC)
ΔV
OUT(START)
t
START
ΔV
OUTLS
Output Continuous Current
Range
Line Regulation Accuracy
Load Regulation Accuracy
Output Ripple Voltage
Turn-On Overshoot
Turn-On Time
Peak Deviation for Dynamic
Load
Settling Time for Dynamic
Load Step
Output Current Limit
t
SETTLE
I
OUTPK
Control Section
V
FB
I
FB
V
OVL
I
TRACK/SS
t
ON(MIN)
R
FBHI
V
OSNS+
,
V
OSNS– CM RANGE
V
DIFF_OUT(MAX)
V
OS
A
V
SR
GBP
CMRR
I
DIFF_OUT
20
25
25
0.594
0.65
1.0
0.60
–12
0.67
1.2
90
60.05
60.40
60.75
4
0.606
–25
0.69
1.4
μs
A
A
V
nA
V
μA
ns
kΩ
V
V
2
mV
V/V
V/μs
MHz
dB
mA
Voltage at V
FB
Pin
Current at V
FB
Pin
Feedback Overvoltage
Lockout
Track Pin Soft-Start Pull-Up
Current
Minimum On-Time
Resistor Between V
OUT_LCL
and V
FB
Pins
Common Mode Input Range
TRACK/SS = 0V
(Note 3)
V
IN
= 12V, Run > 1.4V
0
INTV
CC
– 1.4
1
2
3
Maximum DIFF_OUT Voltage I
DIFF_OUT
= 300μA
Input Offset Voltage
Differential Gain
Slew Rate
Gain Bandwidth Product
Common Mode Rejection
DIFF_OUT Current
(Note 7)
Sourcing
V
OSNS+
= V
DIFF_OUT
= 1.5V, I
DIFF_OUT
= 100μA
60
2
4627f
3
LTM4627
ELECTRICAL CHARACTERISTICS
SYMBOL
PSRR
R
IN
V
PGOOD
PARAMETER
Power Supply Rejection
Ratio
Input Resistance
PGOOD Trip Level
CONDITIONS
5V < V
IN
< 20V (Note 7)
V
OSNS
+ to GND
V
FB
With Respect to Set Output
V
FB
Ramping Negative
V
FB
Ramping Positive
I
PGOOD
= 2mA
6V < V
IN
< 20V
I
CC
= 0 to 50mA
EXTV
CC
Ramping Positive
I
CC
= 25mA, V
EXTVCC
= 5V
250
V
fSET
= 1.2V
V
fSET
= 1V
V
fSET
≥ 2.4V
450
350
700
9
500
400
770
10
250
2.0
0.8
maximum ambient temperature consistent with these specifications is
determined by specific operating conditions in conjunction with board
layout, the rated package thermal resistance and other environmental
factors.
Note 3:
The minimum on-time condition is specified for a peak-to-peak
inductor ripple current of ~40% of I
MAX
Load. (See the Applications
Information section)
Note 4:
See output current derating curves for different V
IN
, V
OUT
and T
A
.
Note 5:
Limit current into the RUN pin to less than 2mA.
Note 6:
Guaranteed by design.
Note 7:
100% tested at wafer level.
l
The
l
denotes the specifications which apply over the full internal operating
temperature range, otherwise specifications are at T
A
= 25°C (Note 2), V
IN
= 12V, per the typical application in Figure 18.
MIN
TYP
100
80
–10
10
0.1
4.8
4.5
5
0.5
4.7
50
100
800
550
450
850
11
0.3
5.2
MAX
UNITS
dB
kΩ
%
%
V
V
%
V
mV
kHz
kHz
kHz
kHz
μA
kΩ
V
V
V
PGL
V
INTVCC
V
EXTVCC
VLDO Ext
f
SYNC
Frequency
Nominal
Frequency Low
Frequency High
I
FREQ
R
MODE_PLLIN
V
IH_MODE_PLLIN
V
IL_MODE_PLLIN
PGOOD Voltage Low
Internal V
CC
Voltage
External V
CC
Switchover
EXTV
CC
Voltage Drop
SYNC Capture Range
Nominal Frequency
Lowest Frequency
Highest Frequency
Frequency Set Current
Mode_PLLIN Input
Resistance
Clock Input Level High
Clock Input Level Low
INTV
CC
Linear Regulator
V
INTVCC
Load Reg INTV
CC
Load Regulation
Oscillator and Phase-Locked Loop
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 LTM4627 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTM4627E is guaranteed to meet performance specifications
over the 0°C to 125°C internal operating temperature range. Specifications
over the full –40°C to 125°C internal operating temperature range are
assured by design, characterization and correlation with statistical process
controls. The LTM4627I is guaranteed to meet specifications over the
full –40°C to 125°C internal operating temperature range. Note that the
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