boost power supply. Included in the package are the
switching controller, power FETs and support components.
Operating over an input voltage range of 4.5V to 36V, the
LTM4609 supports an output voltage range of 0.8V to
34V, set by a resistor. This high efficiency design delivers
up to 4A continuous current in boost mode (10A in buck
mode). Only the inductor, sense resistor, bulk input and
output capacitors are needed to finish the design.
The low profile package enables utilization of unused space
on the bottom of PC boards for high density point of load
regulation. The high switching frequency and current
mode architecture enable a very fast transient response
to line and load changes without sacrificing stability. The
LTM4609 can be frequency synchronized with an external
clock to reduce undesirable frequency harmonics.
Fault protection features include overvoltage and foldback
current protection. The DC/DC μModule™ is offered in a
small thermally enhanced 15mm × 15mm × 2.8mm LGA
package. The LTM4609 is Pb-free and RoHS compliant.
Single Inductor Architecture Allows V
IN
Above,
Below or Equal to V
OUT
Wide V
IN
Range: 4.5V to 36V
Wide V
OUT
Range: 0.8V to 34V
I
OUT
: 4A DC (10A DC in Buck Mode)
Up to 98% Efficiency
Current Mode Control
Power Good Output Signal
Phase-Lockable Fixed Frequency: 200kHz to 400kHz
Ultra-Fast Transient Response
Current Foldback Protection
Output Overvoltage Protection
Small, Low Profile Surface Mount LGA Package
(15mm × 15mm × 2.8mm)
APPLICATIONS
n
n
n
Telecom, Servers and Networking Equipment
Industrial and Automotive Equipment
High Power Battery-Operated Devices
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.
TYPICAL APPLICATION
30V/2A Buck-Boost DC/DC μModule with 5V to 36V Input
V
IN
6.5V TO 36V
CLOCK SYNC
10μF
50V
ON/OFF
V
IN
RUN
PLLIN V
OUT
FCB
5.6μH
SW1
SW2
R
SENSE
SENSE
+
0.1μF
SS
SGND
PGND
SENSE
–
V
FB
2.74k
4609 TA01a
Efficiency and Power Loss
vs Input Voltage
99
6
5
POWER LOSS (W)
4
3
2
1
EFFICIENCY
POWER LOSS
8
12
16
24
20
V
IN
(V)
28
32
36
0
V
OUT
30V
2A
EFFICIENCY (%)
98
97
96
95
94
93
92
91
LTM4609
10μF
50V
+
330μF
50V
R2
15mΩ
2
4609 TA01b
4609f
1
LTM4609
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
(See Table 6 Pin Assignment)
TOP VIEW
BANK 2
M
L
V
IN
............................................................. –0.3V to 36V
V
OUT
............................................................. 0.8V to 36V
INTV
CC
, EXTV
CC
, RUN, SS, PGOOD .............. –0.3V to 7V
SW1, SW2 .................................................... –5V to 36V
V
FB
, COMP ................................................ –0.3V to 2.4V
FCB, STBYMD ....................................... –0.3V to INTV
CC
PLLIN ........................................................ –0.3V to 5.5V
PLLFLTR.................................................... –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
Solder Temperature (Note 3)................................. 245°C
BANK 4
K
J
H
G
BANK 1
BANK 3
BANK 5
F
E
D
C
BANK 6
B
A
1
2
3
4
5
6
7
8
9
10
11
12
LGA PACKAGE
141-LEAD (15mm 15mm
2.8mm)
T
JMAX
= 125°C,
θ
JP
= 4°C/W, WEIGHT = 1.5g
ORDER INFORMATION
LEAD FREE FINISH
LTM4609EV#PBF
LTM4609IV#PBF
PART MARKING*
LTM4609V
LTM4609V
PACKAGE DESCRIPTION
141-Lead (15mm × 15mm × 2.8mm) LGA
141-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. *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/
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.
SYMBOL
Input Specifications
V
IN(DC)
V
IN(UVLO)
I
Q(VIN)
Input DC Voltage
Undervoltage Lockout Threshold
Input Supply Bias Current
Normal
Standby
Shutdown Supply Current
V
IN
Falling
l
l
ELECTRICAL CHARACTERISTICS
PARAMETER
CONDITIONS
MIN
4.5
TYP
MAX
36
UNITS
V
V
mA
mA
μA
3.4
2.8
1.6
35
4
V
RUN
= 0V, V
STBYMD
> 2V
V
RUN
= 0V, V
STBYMD
= Open
60
4609f
2
LTM4609
ELECTRICAL CHARACTERISTICS
SYMBOL
I
OUTDC
PARAMETER
Output Specifications
Output Continuous Current Range
V
IN
= 32V, V
OUT
= 12V
(See Output Current Derating Curves V
IN
= 6V, V
OUT
= 12V
for Different V
IN
, V
OUT
and T
A
)
Reference Voltage Line Regulation
Accuracy
Load Regulation Accuracy
V
IN
= 4.5V to 36V, V
COMP
= 1.2V (Note 4)
V
COMP
= 1.2V to 0.7V
V
COMP
= 1.2V to 1.8V (Note 4)
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Drain to Source Voltage V
DS
= 12V, Bias
Current I
SW
= 10mA
Bias Current I
SW
= 3A
Bias Current I
SW
= 3A
Bias Current I
SW
= 3A
Bias Current I
SW
= 3A
l
l
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
MIN
TYP
10
4
0.002
0.15
–0.15
50
40
25
20
20
20
50
50
50
50
220
220
10
14
14
14
20
20
20
0.02
0.5
–0.5
MAX
UNITS
A
A
%
%
%
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
mΩ
mΩ
mΩ
mΩ
ΔV
FB
/V
FB(NOM)
ΔV
FB
/V
FB(LOAD)
Switch Section
M1 t
r
M1 t
f
M3 t
r
M3 t
f
M2, M4 t
r
M2, M4 t
f
t
1d
t
2d
t
3d
t
4d
Mode Transition 1
Mode Transition 2
M1 R
DS(ON)
M2 R
DS(ON)
M3 R
DS(ON)
M4 R
DS(ON)
Turn-On Time (Note 5)
Turn-Off Time
Turn-On Time
Turn-Off Time
Turn-On Time
Turn-Off Time
M1 Off to M2 On Delay (Note 5)
M2 Off to M1 On Delay
M3 Off to M4 On Delay
M4 Off to M3 On Delay
M2 Off to M4 On Delay
M4 Off to M2 On Delay
Static Drain-to-Source On-
Resistance
Static Drain-to-Source On-
Resistance
Static Drain-to-Source On-
Resistance
Static Drain-to-Source On-
Resistance
Nominal Frequency
Lowest Frequency
Highest Frequency
PLLIN Input Resistance
Phase Detector Output Current
Oscillator and Phase-Locked Loop
f
NOM
f
LOW
f
HIGH
R
PLLIN
I
PLLFLTR
V
PLLFLTR
= 1.2V
V
PLLFLTR
= 0V
V
PLLFLTR
= 2.4V
f
PLLIN
< f
OSC
f
PLLIN
> f
OSC
260
170
340
300
200
400
50
–15
15
330
220
440
kHz
kHz
kHz
kΩ
μA
μA
4609f
3
LTM4609
ELECTRICAL CHARACTERISTICS
SYMBOL
Control Section
V
FB
V
RUN
I
SS
V
STBYMD(START)
V
STBYMD(KA)
V
FCB
I
FCB
V
BURST
DF
(BOOST, MAX)
DF
(BUCK, MAX)
t
ON(MIN, BUCK)
RFBHI
INTV
CC
ΔV
LDO
/V
LDO
V
EXTVCC
ΔV
EXTVCC(HYS)
ΔV
EXTVCC
V
SENSE(MAX)
V
SENSE(MIN, BUCK)
I
SENSE
PGOOD
ΔV
FBH
ΔV
FBL
ΔV
FB(HYS)
V
PGL
I
PGOOD
PGOOD Upper Threshold
PGOOD Lower Threshold
PGOOD Hysteresis
PGOOD Low Voltage
PGOOD Leakage Current
V
FB
Rising
V
FB
Falling
V
FB
Returning
I
PGOOD
= 2mA
V
PGOOD
= 5V
5.5
–5.5
7.5
–7.5
2.5
0.2
0.3
1
10
–10
%
%
%
V
μA
Feedback Reference Voltage
RUN Pin ON/OFF Threshold
Soft-Start Charging Current
Start-Up Threshold
Keep-Active Power On Threshold
Forced Continuous Threshold
Forced Continuous Pin Current
Burst Inhibit (Constant Frequency)
Threshold
Maximum Duty Factor
Maximum Duty Factor
V
FCB
= 0.85V
Measured at FCB Pin
% Switch M4 On
% Switch M1 On
V
RUN
= 2.2V
V
STBYMD
Rising
V
STBYMD
Rising, V
RUN
= 0V
0.76
–0.3
V
COMP
= 1.2V
l
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.
PARAMETER
CONDITIONS
MIN
0.792
1
1
0.4
TYP
0.8
1.6
1.7
0.7
1.25
0.8
–0.2
5.3
99
99
200
99.5
V
IN
> 7V, V
EXTVCC
= 5V
I
CC
= 0mA to 20mA, V
EXTVCC
= 5V
I
CC
= 20mA, V
EXTVCC
Rising
I
CC
= 20mA, V
EXTVCC
= 6V
Boost Mode
Buck Mode
Discontinuous Mode
V
SENSE–
= V
SENSE+
= 0V
l
l
l
l
MAX
0.808
2.2
UNITS
V
V
μA
V
V
0.84
–0.1
5.5
V
μA
V
%
%
Minimum On-Time for Synchronous Switch M1 (Note 6)
Switch in Buck Operation
Resistor Between V
OUT
and V
FB
Pins
Internal V
CC
Voltage
Internal V
CC
Load Regulation
EXTV
CC
Switchover Voltage
EXTV
CC
Switchover Hysteresis
EXTV
CC
Switch Drop Voltage
Maximum Current Sense Threshold
Minimum Current Sense Threshold
Sense Pins Total Source Current
250
100.5
6.3
2
ns
kΩ
V
%
V
mV
100
6
0.3
5.6
300
60
160
–130
–6
–380
Internal V
CC
Regulator
5.7
5.4
150
190
–150
mV
mV
mV
mV
μA
Current Sensing Section
–95
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 LTM4609E 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 LTM4609I is guaranteed over the full
–40°C to 85°C temperature range.
Note 3:
See Application Note 100.
Note 4:
The LTM4609 is tested in a feedback loop that servos V
COMP
to a
specified voltage and measures the resultant V
FB
.
Note 5:
Turn-on and turn-off time are measured using 10% and 90%
levels. Transition delay time is measured using 50% levels.