LTM4648
Low V
IN
, 10A Step-Down
µModule Regulator
FEATURES
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DESCRIPTION
The
LTM
®
4648
is a 10A low V
IN
step-down
DC/DC µModule
®
(micromodule) regulator. Included in
the package are the switching controller, power FETs,
inductor and all support components. Operating over
an input voltage range of 2.375V to 5.5V, the LTM4648
supports an output voltage range of 0.6V to 5V, set by a
single external resistor. This high efficiency design delivers
up to 10A continuous current. Only bulk input and output
capacitors are needed.
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, programmable multiphase
operation and output voltage tracking for supply rail
sequencing.
Fault protection features include overvoltage protec-
tion, overcurrent protection and thermal shutdown. The
LTM4648 is offered in a small 9mm × 15mm × 4.92mm
BGA package available with SnPb or RoHS compliant ter-
minal finish. For up to 16V
IN
operation, see the LTM4649.
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. Patents, including 5481178, 5705919, 5929620, 6100678, 6144194, 6177787, 6304066
and 6580258. Other patents pending.
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10A DC Output Current
Input Voltage Range: 2.375V to 5.5V
Output Voltage Range: 0.6V to 5V
No Heat Sink or Current Derating Up to 85°C
Ambient Temperature
±1.5% Maximum Total DC Output Error
Multiphase Operation with Current Sharing
Remote Sense Amplifier
Built-In Temperature Monitor
Selectable Pulse-Skipping Mode/Burst Mode
®
Operation for High Efficiency at Light Load
Soft-Start/Voltage Tracking
Protection: Output Overvoltage and Overcurrent
Foldback
See
LTM4649
for Up to 16V
IN
Operation
9mm × 15mm × 4.92mm BGA Package
APPLICATIONS
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Telecom, Networking and Industrial Equipment
Point of Load Regulation
TYPICAL APPLICATION
2.375V to 5.5V Input, 1.5V Output DC/DC
µModule Regulator
V
IN
2.375V TO 5.5V
PINS NOT USED
IN THIS CIRCUIT:
INTV
CC
SW
RUN
PHMODE
TEMP
COMP
PGOOD
CLKIN
CLKOUT
22µF
10V
×2
V
IN
V
OUT
DIFFP
DIFFN
LTM4648
MODE
TRACK/SS
0.1µF
GND
V
OUT_LCL
DIFFOUT
V
FB
6.65k
4648 TA01a
Efficiency and Power Loss
at 5V and 3.3V Input
100
95
90
EFFICIENCY (%)
85
80
75
70
65
0
2
4
6
2.8
2.4
LOAD CURRENT (A)
2.0
1.6
1.2
0.8
V
IN
= 3.3V 0.4
V
IN
= 5V
0
10
8
4648 TA01b
Current Derating, 5V to 1.5V
OUT
with No Heat Sink
12
10
POWER LOSS (W)
8
6
4
2
0
400LFM
200LFM
0LFM
0
40
60
80
100
20
AMBIENT TEMPERATURE (°C)
120
V
OUT
1.5V
100µF
10A
6.3V
×2
LOAD CURRENT (A)
4648 TA01c
Document Feedback
For more information
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1
Rev A
LTM4648
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
A
1
CLKIN
PHMODE
MODE
2
3
4
5
NC
SW
COMP
FB
TRACK/SS
B
GND
TOP VIEW
C D E
V
IN
NC
GND
CLKOUT
FREQ
F
G
V
IN
............................................................... –0.3V to 6V
V
OUT
, INTV
CC
, PGOOD, RUN (Note 5) .......... –0.3V to 6V
MODE, CLKIN, TRACK/SS, DIFFP, DIFFN,
DIFFOUT, PHASMD ............................... –0.3V to INTV
CC
V
FB
............................................................ –0.3V to 2.7V
COMP (Note 6) .......................................... –0.3V to 2.7V
INTV
CC
Peak Output Current (Note 6) ..................100mA
Internal Operating Temperature Range
(Note 2).................................................. –55°C to 125°C
Storage Temperature Range .................. –55°C to 125°C
Peak Solder Reflow Body Temperature ................. 245°C
TEMP 6
PGOOD
7
8
9
10
11
DIFFN
DIFFP
DIFFOUT
V
OUT_LCL
GND
V
OUT
BGA PACKAGE
68-LEAD (9mm
×
15mm
×
4.92mm)
T
JMAX
= 125°C,
θ
JA
= 14°C/W,
θ
JCbottom
= 5°C/W,
θ
JCtop
= 20°C/W
WEIGHT = 1.0g
ORDER INFORMATION
PART MARKING*
PART NUMBER
LTM4648EY#PBF
LTM4648IY#PBF
LTM4648IY
PAD OR BALL FINISH
SAC305 (RoHS)
SnPb (63/37)
DEVICE
LTM4648Y
LTM4648Y
LTM4648Y
FINISH CODE
e1
e0
• This product is not recommended for second side reflow.
This product is moisture sensitive. For more information, go to
Recommended BGA PCB Assembly and Manufacturing Procedures.
PACKAGE
TYPE
BGA
MSL
RATING
3
TEMPERATURE RANGE
(SEE NOTE 2)
–40°C to 125°C
• Device temperature grade is indicated by a label on the shipping container.
• Pad or ball finish code is per IPC/JEDEC J-STD-609.
•
BGA Package and Tray Drawings
2
Rev A
For more information
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LTM4648
ELECTRICAL CHARACTERISTICS
SYMBOL
V
IN
V
OUT(RANGE)
V
OUT(DC)
PARAMETER
Input DC Voltage
Output Voltage Range
Output Voltage, Total Variation with
Line and Load
C
IN
= 10µF × 1,C
OUT
= 100µF Ceramic,
100µF POSCAP R
FB
= 6.65k, MODE = GND,
,
V
IN
= 2.375V to 5.5V, I
OUT
= 0A to 10A
V
RUN
Rising
V
IN
= 5V, V
OUT
= 1.5V, Burst Mode Operation
V
IN
= 5V, V
OUT
= 1.5V, Pulse-Skipping Mode
V
IN
= 5V, V
OUT
= 1.5V, Switching Continuous
Shutdown, RUN = 0, V
IN
= 5V
V
IN
= 5.5V, V
OUT
= 1.5V, I
OUT
= 10A
V
IN
= 5V, V
OUT
= 1.5V (Note 4)
V
OUT
= 1.5V, V
IN
from 2.375V to 5.5V I
OUT
= 0A
V
OUT
= 1.5V, I
OUT
= 0A to 10A, V
IN
= 5V (Note 4)
I
OUT
= 0A, C
OUT
= 100µF Ceramic, 100µF POSCAP
,
V
IN
= 5V, V
OUT
= 1.5V
C
OUT
= 100µF Ceramic, 100µF POSCAP
,
V
OUT
= 1.5V, I
OUT
= 0A, V
IN
= 5V
C
OUT
= 100µF Ceramic, 100µF POSCAP
,
No Load, TRACK/SS = 0.01µF V
IN
= 5V
,
Load: 0% to 50% to 0% of Full Load,
C
OUT
= 100µF Ceramic, 100µF POSCAP
,
V
IN
= 5V, V
OUT
= 1.5V
Load: 0% to 50% to 0% of Full Load,
C
OUT
= 100µF Ceramic, 100µF POSCAP
,
V
IN
= 5V, V
OUT
=1.5V
V
IN
= 5V, V
OUT
= 1.5V (Note 4)
I
OUT
= 0A, V
OUT
= 1.5V
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
= 5V per typical application.
CONDITIONS
l
l
l
MIN
2.375
0.6
1.477
TYP
MAX
5.5
5
UNITS
V
V
V
1.50
1.523
Input Specifications
V
RUN
V
RUN(HYS)
I
Q(VIN)
RUN Pin On Threshold
RUN Pin On Hysteresis
Input Supply Bias Current
1.1
1.25
150
5.5
25
100
2.5
3.3
0
0.010
0.15
15
20
5
60
10
0.04
0.5
1.4
V
mV
mA
mA
mA
mA
A
A
%/V
%
mV
mV
ms
mV
I
S(VIN)
I
OUT(DC)
ΔV
OUT(LINE)
V
OUT
ΔV
OUT(LOAD)
V
OUT
V
OUT(AC)
ΔV
OUT(START)
t
START
ΔV
OUTLS
t
SETTLE
I
OUTPK
V
FB
I
FB
V
OVL
I
TRACK/SS
t
ON(MIN)
R
FBHI
DIFFP DIFFN CM
,
RANGE
V
DIFFOUT(MAX)
V
OS
A
V
SR
Input Supply Current
Output Continuous Current Range
Line Regulation Accuracy
Load Regulation Accuracy
Output Ripple Voltage
Turn-On Overshoot
Turn-On Time
Peak Deviation for Dynamic Load
Output Specifications
Settling Time for Dynamic Load Step
20
µs
Output Current Limit
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
Maximum DIFFOUT Voltage
Input Offset Voltage
Differential Gain
Slew Rate
11
0.593
0.64
1.0
9.90
0.60
–12
l
A
0.607
–25
0.68
1.4
10.10
3.6
V
nA
V
µA
ns
kΩ
V
V
4
1
2
mV
V/V
V/µs
Control Specifications
0.66
1.2
90
10
TRACK/SS = 0V
(Note 3)
V
IN
= 5V, Run > 1.4V
I
DIFFOUT
= 300µA
V
OSNS
+ = V
DIFFOUT
= 1.5V, I
DIFFOUT
= 100µA
0
INTV
CC
– 1.4
For more information
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3
Rev A
LTM4648
ELECTRICAL CHARACTERISTICS
SYMBOL
GBP
CMRR
I
DIFFOUT
R
IN
V
PGOOD
V
PGL
V
INTVCC
PARAMETER
Gain Bandwidth Product
Common Mode Rejection
DIFFOUT Current
Input Resistance
PGOOD Trip Level
(Note 6)
Sourcing
V
OSNS
+ to GND
V
FB
With Respect to Set Output
V
FB
Ramping Negative
V
FB
Ramping Positive
I
PGOOD
= 2mA
2.375V ≤ V
IN
≤ 5V
V
IN
= 5.5V
I
CC
= 0mA to 50mA
250
400
2.0
0.8
Note 3:
The minimum on-time condition is tested at wafer sort.
Note 4:
See output current derating curves for different V
IN
, V
OUT
and T
A
.
Note 5:
Guaranteed by design.
Note 6:
100% tested at wafer level.
450
250
4.8
5.15
2
80
–10
10
0.1
5
5.25
0.5
650
500
0.3
5.2
5.35
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
= 5V per typical application.
CONDITIONS
MIN
TYP
3
60
MAX
UNITS
MHz
dB
mA
kΩ
%
%
V
V
V
%
kHz
kHz
kΩ
V
V
PGOOD Voltage Low
Internal V
CC
Voltage
INTV
CC
Linear Regulator
V
INTVCC
Load Reg INTV
CC
Load Regulation
Oscillator and Phase-Locked Loop
f
SYNC
f
S
R
MODE
V
IH_CLKIN
V
IL_CLKIN
SYNC Capture Range
Nominal Switching Frequency
Mode Input Resistance
Clock Input Level High
Clock Input Level Low
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. Notes are automatically numbered when you apply
the note style.
Note 2:
The LTM4648 is tested under pulsed load conditions such that T
J
≈
T
A
. The LTM4648E is guaranteed to meet performance specifications over
the 0°C to 125°C internal operating temperature range. Specifications over
the –40°C to 125°C internal operating temperature range are assured by
design, characterization and correlation with statistical process controls.
The LTM4648I is guaranteed to meet specifications over the –40°C to
125°C internal operating temperature range. Note that the 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.
4
Rev A
For more information
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LTM4648
TYPICAL PERFORMANCE CHARACTERISTICS
2.5V
IN
Efficiency
100
95
90
EFFICIENCY (%)
EFFICIENCY (%)
85
80
75
70
65
0
2
4
6
V
OUT
= 1V
V
OUT
= 1.2V
V
OUT
= 1.5V
V
OUT
= 1.8V
8
10
4648 G01
3.3V
IN
Efficiency
100
95
90
85
80
75
70
65
0
2
4
6
V
OUT
= 1V
V
OUT
= 1.2V
V
OUT
= 1.5V
V
OUT
= 1.8V
V
OUT
= 2.5V
8
10
4648 G02
5V
IN
Efficiency
100
95
90
EFFICIENCY (%)
85
80
75
70
65
0
2
4
6
V
OUT
= 1V
V
OUT
= 1.2V
V
OUT
= 1.5V
V
OUT
= 1.8V
V
OUT
= 2.5V
V
OUT
= 3.3V
8
10
4648 G03
LOAD CURRENT (A)
LOAD CURRENT (A)
LOAD CURRENT (A)
100
90
80
EFFICIENCY (%)
CCM, Burst Mode and Pulse-
Skipping Mode Efficiency
(V
IN
= 3.3V, V
OUT
= 1.5V)
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
10
4648 G04
CCM, Burst Mode and Pulse-
Skipping Mode Efficiency
(V
IN
= 5V, V
OUT
= 1.5V)
V
OUT
100mV/DIV
AC-COUPLED
I
OUT
5A/DIV
AC-COUPLED
3.3V
IN
, 1V
OUT
Load Transient
70
60
50
40
30
20
10
0
0.01
CCM
Burst Mode OPERATION
PULSE SKIPPING
0.1
1
LOAD CURRENT (A)
0
0.01
CCM
Burst Mode OPERATION
PULSE SKIPPING
0.1
1
LOAD CURRENT (A)
10
4648 G05
4648 G06
20µs/DIV
,
3.3V
IN
, 1V
OUT
, 5A TO 10A LOAD STEP 5A/µs
,
C
OUT
= 1 • 22µF 6.3V, 1210 + 2 • 100µF 1210
CERAMIC CAPACITORS
NO C
FF
CAPACITOR
5V
IN
, 1V
OUT
Load Transient
V
OUT
100mV/DIV
AC-COUPLED
I
OUT
5A/DIV
AC-COUPLED
4648 G07
20µs/DIV
5V
IN
, 1V
OUT
, 5A TO 10A LOAD STEP 5A/µs
,
,
C
OUT
= 1 • 22µF 6.3V, 1210 + 2 • 100µF 6.3V
1210 CERAMIC CAPACITORS
NO C
FF
CAPACITOR
3.3V
IN
, 1.5V
OUT
Load Transient
V
OUT
100mV/DIV
AC-COUPLED
I
OUT
5A/DIV
AC-COUPLED
4648 G08
20µs/DIV
3.3V
IN
, 1.5V
OUT
, 5A TO 10A LOAD STEP 5A/µs
,
,
C
OUT
= 1 • 22µF 6.3V, 1210 + 2 • 100µF 6.3V
1210 CERAMIC CAPACITORS
NO C
FF
CAPACITOR
5V
IN
, 1.5V
OUT
Load Transient
V
OUT
100mV/DIV
AC-COUPLED
I
OUT
5A/DIV
AC-COUPLED
4648 G09
20µs/DIV
5V
IN
, 1.5V
OUT
, 5A TO 10A LOAD STEP 5A/µs
,
,
C
OUT
= 1 • 22µF 6.3V, 1210 + 2 • 100µF 6.3V
1210 CERAMIC CAPACITORS
NO C
FF
CAPACITOR
For more information
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5
Rev A