LTC7150S
20V, 20A Synchronous
Step-Down Regulator
FEATURES
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DESCRIPTION
The
LTC
®
7150S
is a high efficiency monolithic synchronous
buck regulator capable of delivering 20A to the load. It uses
a phase lockable controlled on-time constant frequency,
current mode architecture. PolyPhase operation allows
multiple LTC7150S regulators to run out-of-phase, which
reduces the amount of input and output capacitors required.
The operating supply voltage range is from 3.1V to 20V.
The operating frequency is programmable from 400kHz
to 3MHz with an external resistor. The high frequency ca-
pability allows the use of physically smaller inductor and
capacitor sizes. For switching noise sensitive applications,
the LTC7150S can be externally synchronized from 400kHz
to 3MHz. The PHMODE pin allows the user control of the
phase of the outgoing clock signal. The unique constant
frequency/controlled on-time architecture is ideal for
high step-down ratio applications that operate at high
frequencies while demanding fast transient response.
The LTC7150S uses second generation Silent Switcher
technology including integrated bypass capacitors to
deliver a highly efficient solution at high frequencies with
excellent EMI performance.
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Silent Switcher
®
2 Architecture for Low EMI
V
IN
Range: 3.1V to 20V
V
OUT
Range: 0.6V to 5.5V
Differential V
OUT
Remote Sense
Adjustable Frequency: 400kHz to 3MHz
PolyPhase
®
Operation: Up to 12 Phases
Output Tracking and Soft-Start
Reference Accuracy: 0.6V ±1% Over Temperature
Current Mode Operation for Excellent Line and Load
Transient Response
Accurate 1.2V Run Pin Threshold
Supports Forced Continuous/Discontinuous Modes
42-Lead 6mm × 5mm × 1.3mm BGA Package
APPLICATIONS
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Server Power Applications
Distributed Power Systems
Point of Load Supply for ASIC, FPGA, DSP µP etc.
, ,
All registered trademarks and trademarks are the property of their respective owners.
TYPICAL APPLICATION
12V
IN
to 1.2V
OUT
Application
V
IN
3.1V TO 20V
22µF
×2
0.25µH
RUN
PVIN
SVIN
SW
10k
10k
V
OUT–
PGOOD
MODE/SYNC
SGND
ITH
100µF
×2
100
V
OUT
1.2V/20A
SV
IN
= 5V
95
EFFICIENCY (%)
90
85
80
75
70
22pF
7150S TA01a
Efficiency and Power Loss
12
10
8
6
4
2
0
POWER LOSS (W)
LTC7150S
FB
+
330µF
PHMODE
TRACK/SS
CLKOUT
INTV
CC
4.7µF
RT
162k
10k
1nF
0
4
8
12
I
OUT
(A)
16
20
7150S TA01b
7150sfa
For more information
www.linear.com/LTC7150S
1
LTC7150S
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
TOP VIEW
1
PHMODE
CLKOUT RUN M/S TRACK/SS SGND INTVCC
PV
IN
, SV
IN
................................................. –0.3V to 22V
RUN Voltage............................................. –0.3V to SV
IN
MODE/SYNC, TRACK/SS Voltage ......... –0.3V to INTV
CC
ITH, RT, PGOOD Voltage ........................... –0.3V to 3.6V
PHMODE, CLK Voltage .............................. –0.3V to 3.6V
V
OUT–
Voltage ........................................... –0.3V to 0.3V
FB Voltage ................................................. –0.3V to 3.6V
Operating Junction Temperature Range ................ 125°C
Storage Temperature Range .................. –65°C to 150°C
Maximum Internal Temperature ............................ 125°C
Peak Reflow Solder Body Temperature ................. 260°C
2
PGOOD
3
RT
4
ITH
5
FB
6
V
OUT–
A
B
SVIN
PVIN
PVIN
PVIN
SW
SW
SW
SW
SW
SW
SW
SW
SW
SW
PVIN
PVIN
PVIN
C
PVIN
D
PGND PGND
PGND PGND
PGND PGND
PGND PGND
E
PGND PGND
F
PGND PGND
G
BGA PACKAGE
42-LEAD (6mm
×
5mm
×
1.30mm)
T
JMAX
= 125°C,
θ
JA
= 21°C/W
ORDER INFORMATION
PART NUMBER
LTC7150SEY#PBF
LTC7150SIY#PBF
PAD OR BALL FINISH
SAC305 (RoHS)
SAC305 (RoHS)
http://www.linear.com/product/LTC7150S#orderinfo
PART MARKING*
DEVICE
7150S
7150S
FINISH CODE
e1
e1
PACKAGE
TYPE
BGA
BGA
MSL
RATING
3
3
TEMPERATURE RANGE
(SEE NOTE 2)
–40°C to 125°C
–40°C to 125°C
• Device temperature grade is indicated by a label on the shipping container. • Recommended BGA PCB Assembly and Manufacturing Procedures:
www.linear.com/BGA-assy
• Pad or ball finish code is per IPC/JEDEC J-STD-609.
• Terminal Finish Part Marking:
www.linear.com/leadfree
• This product is not recommended for second side reflow. For more
information, go to
www.linear.com/BGA-assy
• BGA Package and Tray Drawings:
www.linear.com/packaging
• This product is moisture sensitive. For more information, go to:
www.linear.com/BGA-assy
7150sfa
2
For more information
www.linear.com/LTC7150S
LTC7150S
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2). V
IN
= 12V, unless otherwise noted.
SYMBOL
SV
IN
PV
IN
V
OUT
I
Q
V
FB
∆V
FB(LINE+LOAD)
I
FB
g
m
(EA)
t
ON(MIN)
t
OFF(MIN)
I
LIM
I
LIM-ITH
PARAMETER
SV
IN
Operating Voltage
PV
IN
Operating Voltage
V
OUT
Operating Voltage
Input Quiescent Current (Note 3)
Feedback Reference Voltage (Note 4)
Feedback Voltage Line and Load Regulation
(Note 4)
Feedback Pin Input Current
Error Amplifier Transconductance
Minimum On-Time
Minimum Off-Time
Positive Inductor Valley Current Limit
Current Limit at Different ITH Voltage
FB = 0.58V
ITH = 1.4V
ITH = 1V
ITH = 0.6V
ITH = 0.2V
INTV
CC
= 3.3V
INTV
CC
= 3.3V
V
IN
= 20V, V
SW
= 0V
V
IN
= 20V, V
SW
= 20V
INTV
CC
Falling
INTV
CC
Hysteresis (Rising)
2.45
1.15
l
l
l
l
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
l
MIN
3.1
0.6
TYP
MAX
20
20
5.5
UNITS
V
V
V
mA
µA
V
V
%
nA
mS
nS
nS
A
A
A
A
A
mΩ
mΩ
Active Mode
Shutdown Mode; V
RUN
= 0V
ITH = 1.0V
ITH = 1.0V, –40°C to 125°C
l
l
2
20
0.598
0.594
0.600
0.600
0.2
4
40
0.602
0.606
0.5
±50
ITH = 1.0V
l
1.0
1.3
20
50
1.6
25
27
14.5
2.5
–9.5
–21
21
9.5
–2.5
–14.5
–27
24
12
0
–12
–24
6
2.5
0.1
1
2.6
250
1.20
100
3.3
8
10
–8
10
8
6
25
6
R
TOP
R
BOT
I
SW
(Note 5)
V
UVLO
V
RUN
I
RUN
V
INTVCC
OV
UV
R
PGOOD
I
PGOOD
t
PGOOD
I
TRACK/SS
f
OSC
f
SYNC
MODE/SYNC
Top Power NMOS On-Resistance
Bottom Power NMOS On-Resistance
Top Switch Leakage
Bottom Switch Leakage
INTV
CC
Undervoltage Lockout Threshold
RUN Rising
RUN Falling Hysteresis
Run Leakage Current
Internal V
CC
Voltage
Output Overvoltage
PGOOD Upper Threshold
Output Undervoltage
PGOOD Lower Threshold
PGOOD Pull-Down Resistance
PGOOD Leakage
PGOOD Delay
Track Pull-Up Current
Oscillator Frequency
SYNC Capture Range
MODE/SYNC Threshold Input High
MODE/SYNC Threshold Input Low
1
50
2.75
1.25
100
µA
µA
V
mV
V
mV
nA
V
%
mV
%
mV
Ω
µA
cycles
cycles
3.2
V
FB
Rising
V
FB
Falling Hysteresis
V
FB
Falling
V
FB
Rising Hysteresis
V
PGOOD
= 100mV
V
FB
= 0.6V
PGOOD Low to High
PGOOD High to Low
V
TRACK/SS
= 0V
RT = 162kΩ
% of Programmed Frequency
l
3.4
10
–10
15
2
6
–6
10
1.1
130
1
µA
MHz
%
V
V
0.9
70
0.3
1
7150sfa
For more information
www.linear.com/LTC7150S
3
LTC7150S
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C (Note 2). V
IN
= 12V, unless otherwise noted.
SYMBOL
I
MODE/SYNC
V
CLKOUT
PHMODE
PARAMETER
MODE/SYNC Current
Clock Output High Voltage
Clock Output Low Voltage
PHMODE Threshold
180° (2-Phase)
90° (4-Phase)
120° (3-Phase)
V
IN
Rising
V
IN
Falling
CONDITIONS
MODE/SYNC = 0V
V
INTVCC
– 0.2
V
INTVCC
– 0.1
1.0
22.5
20
24.5
21.5
MIN
TYP
6
V
INTVCC
0
MAX
14
0.2
V
INTVCC
– 1
0.1
26.5
23
UNITS
µA
V
V
V
V
V
V
V
ELECTRICAL CHARACTERISTICS
V
INOV
V
IN
Overvoltage Threshold
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 LTC7150S is tested under pulsed load conditions such
that T
J
≈ T
A
. The LTC7150SE is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC7150SI is guaranteed over the –40°C to 125°C operating junction
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
impedance and other environmental factors. The junction temperature
(T
J
, in °C) is calculated from the ambient temperature (T
A
, in °C) and
power dissipation (P
D
, in Watts) according to the formula:
T
J
= T
A
+ (P
D
•
θ
JA
),
where
θ
JA
(in °C/W) is the package thermal impedance.
Note 3:
The quiescent current in forced continuous mode does not include
switching loss of the power FETs.
Note 4:
The LTC7150S is tested in a feedback loop that servos V
ITH
to a
specified voltage and measures the resultant V
FB
.
Note 5:
There is additional switch current due to internal resistor to ground.
7150sfa
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For more information
www.linear.com/LTC7150S
LTC7150S
TYPICAL PERFORMANCE CHARACTERISTICS
otherwise noted.
Efficiency vs Load Current 500kHz
100
95
EFFICIENCY (%)
EFFICIENCY (%)
90
85
80
75
70
V
OUT
= 1.0V
V
OUT
= 1.2V
V
OUT
= 1.5V
0
4
8
12
I
OUT
(A)
16
20
7150S G01
T
A
= 25°C, V
IN
= 12V, V
OUT
= 1.2V, unless
Efficiency vs Load Current 1MHz
100
95
90
85
80
75
70
V
OUT
= 1.0V
V
OUT
= 1.2V
V
OUT
= 1.5V
0
4
8
12
I
OUT
(A)
16
20
7150S G02
Efficiency vs Load Current 2MHz
100
95
EFFICIENCY (%)
90
85
80
75
70
V
OUT
= 1.0V
V
OUT
= 1.2V
V
OUT
= 1.5V
0
4
8
12
I
OUT
(A)
16
20
7150S G03
PV
IN
= 12V, SV
IN
= 5V
L = 0.33µH (DCR = 0.37m )
PV
IN
= 12V, SV
IN
= 5V
L = 0.25µH (DCR = 0.37m )
PV
IN
= 12V, SV
IN
= 5V
L = 0.15µH (DCR = 0.37m )
Transient Response, DCM
V
OUT
AC–COUPLED
50mV/DIV
V
OUT
AC–COUPLED
50mV/DIV
Transient Response, CCM
1.00
0.75
0.50
NORMALIZED (%)
0.25
0
–0.25
–0.50
Load Regulation vs Load Current
V
OUT
= 1.2V
I
L
10A/DIV
I
L
10A/DIV
20µs/DIV
V
IN
= 12V, V
OUT
= 1.2V
I
OUT
= 1.5A to 15A, L = 0.15µH, f
SW
= 1MHz
R
ITH
= 10kΩ, C
ITH
= 1.0nF C
ITHP
= 100pF
,
R
FB1
= 10kΩ, R
FB2
= 10kΩ
C
OUT
= 2 × 100uF + 2 × 330µF
7150S G04
20µs/DIV
7150S G05
–0.75
–1.00
0
4
8
12
I
OUT
(A)
16
20
7150S G06
V
IN
= 12V, V
OUT
= 1.2V
I
OUT
= 1.5A TO 15A, L = 0.15µH, f
SW
= 1MHz
R
ITH
= 20kΩ, C
ITH
= 220pF C
ITHP
= 22pF
,
R
FB1
= 10kΩ, R
FB2
= 10kΩ
C
OUT
= 2 × 100µF + 2 × 330µF
RDS
ON
vs Temperature
10
9
8
7
RDS
ON
(mΩ)
6
5
4
3
2
1
0
–55 –35 –15
BOT FET
TOP FET
5 25 45 65 85 105 125
TEMPERATURE (°C)
7150S G07
Output Tracking
40
V
TRACK/SS
500mV/DIV
V
OUT
1V/DIV
I
L
10A/DIV
Shutdown Current vs V
IN
30
I
Q
(uA)
200µs/DIV
V
IN
= 12V, R
OUT
= 0.1Ω
R
FB1
= 10kΩ, R
FB2
= 10kΩ
V
TRACK
= 0V to 1V
7150S G08
20
10
0
0
5
10
V
IN
(V)
15
20
7150S G09
7150sfa
For more information
www.linear.com/LTC7150S
5