LINER LTM8027IV 60v, 4a dc/dc module regulator Datasheet

LTM8027
60V, 4A DC/DC µModule
Regulator
FEATURES
DESCRIPTION
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The LTM®8027 is a complete 4A, DC/DC step-down power
supply. Included in the package are the switching controller, power switches, inductor and all support components.
Operating over an input voltage range of 4.5V to 60V (7.5V
minimum voltage to start), the LTM8027 supports output
voltages up to 24V, and a switching frequency range of
100kHz to 500kHz, each set by a single resistor. Only the
bulk input and output filter capacitors are needed to finish
the design.
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Complete Switch Mode Power Supply
Wide Input Voltage Range: 4.5V to 60V
(7.5V Minimum Voltage to Start)
Wide Output Voltage Range: 2.5V to 24V
(See Table 2)
4A Output Current
Programmable Soft-Start
10μA Shutdown Supply Current
Selectable Switching Frequency Current Mode
Control
Up to 95% Efficiency
Pb-Free (e4) RoHS Compliant Package with
Gold Pad Finish
Tiny, Low Profile (15mm × 15mm × 4.32mm)
Surface Mount LGA Package
The low profile package (4.32mm) enables utilization of
unused space on the bottom of PC boards for high density point of load regulation. A built-in soft-start timer is
adjustable with a small capacitor.
The LTM8027 is packaged in a thermally enhanced, compact
(15mm × 15mm) and low profile (4.32mm) over-molded
land grid array (LGA) package suitable for automated
assembly by standard surface mount equipment. The
LTM8027 is Pb-free and RoHS compliant.
APPLICATIONS
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12V and 42V Automotive and Heavy Equipment
48V Telecom Power Supplies
Avionics and Industrial Control Systems
Distributed Power Converters
L, LT, LTC, LTM, μModule, Linear Technology and the Linear logo are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
48W, 16VIN to 60VIN DC/DC μModule® Regulator
4.7μF
s2
VIN
1M
48.7k
VOUT
12V
4A
VOUT
LTM8027
RUN
BIAS1
SS
BIAS2
SYNC
AUX
RT
ADJ
GND
100
24VIN
90
80
22μF
s4
56.2k
EFFICIENCY (%)
VIN
16V TO 60V
Efficiency vs Load
70
60
50
40
30
3845 TA01a
20
10
0
0
1
2
LOAD (A)
3
4
8027 TA01b
8027f
1
LTM8027
ABSOLUTE MAXIMUM RATINGS
PIN CONFIGURATION
(Note 1)
VIN Voltage ................................................................65V
BIAS1, BIAS2 ............................................................15V
SYNC, ADJ, RT, RUN, SS Voltages ..............................5V
Current Into RUN Pin (Note 2) .................................1mA
VOUT, AUX .................................................................25V
Current Out of AUX ............................................. 200mA
Internal Operating Temperature
(Note 3).................................................. –40°C to 125°C
Maximum Soldering Temperature ......................... 245°C
Storage Temperature Range .................. –55°C to 125°C
TOP VIEW
11
10
9
8
AUX 7
BIAS1 6
SS 5
RUN 4
BIAS2 3
ADJ 2
1
VOUT
BANK 1
GND
BANK 2
VIN
BANK 3
A B C D E F G H J K L
SYNC
RT
LGA PACKAGE
113-LEAD (15mm s 15mm s 4.32mm)
TJMAX = 125°C, θJA = 12.2°C/W, θJC(TOP) = 9.3°C/W,
θJC(BOTTOM) = 3.6°C/W, θJBOARD = 7.54°C/W
θ VALUES DETERMINED PER JESD 51-9
WEIGHT = 2.6 GRAMS
ORDER INFORMATION
LEAD FREE FINISH
TRAY
PART MARKING
PACKAGE DESCRIPTION
INTERNAL TEMPERATURE RANGE
LTM8027EV#PBF
LTM8027EV#PBF
LTM8027V
113-Lead (15mm × 15mm × 4.32mm) LGA –40°C to 125°C
LTM8027IV#PBF
LTM8027IV#PBF
LTM8027V
113-Lead (15mm × 15mm × 4.32mm) LGA –40°C to 125°C
LTM8027MPV#PBF
LTM8027MPV#PBF
LTM8027V
113-Lead (15mm × 15mm × 4.32mm) LGA –55°C to 125°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://linear.com/packaging/
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 20V, BIAS1 = BIAS2 = 10V, RUN = 2V, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
VIN
Input DC Voltage
(Note 5)
VOUT
Maximum Output DC Voltage
0 < IOUT ≤ 4A, VIN = 48V
IOUT
Output DC Current
VIN ≤ 60V, VOUT = 12V, (Note 4)
VIN(START)
Minimum Start Voltage
ΔVOUT/ΔVIN
Line Regulation
VOUT = 12V, 15V< VIN < 60V, ILOAD = 4A
MIN
l
TYP
4.5
MAX
60
24
0
UNITS
V
V
4
A
7.5
V
0.2
%
ΔVOUT/ΔILOAD
Load Regulation
VOUT = 12V, VIN = 24V, 0A < ILOAD ≤ 4A
0.2
%
VUVLO(RISING)
Input Undervoltage Lockout Threshold
(Rising)
(Note 5)
4.6
V
VUVLO(FALLING)
Input Undervoltage Lockout Threshold
(Falling)
(Note 5)
3.7
V
8027f
2
LTM8027
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VIN = 20V, BIAS1 = BIAS2 = 10V, RUN = 2V, unless otherwise noted.
SYMBOL
PARAMETER
VADJ
ADJ Voltage
IQVIN
Quiescent Current into IN
VBIAS1
BIAS1 Undervoltage Lockout (Rising)
BIAS1 Undervoltage Lockout (Falling)
IBIAS1
Current into BIAS1
VBIAS2
CONDITIONS
MIN
l
TYP
1.224
1.215
VBIAS = VAUX, VOUT = 12VDC, No Load
VRUN = 0V
MAX
UNITS
1.238
1.245
V
V
39
9
mA
μA
6.5
6
V
V
25
25
mA
μA
Minimum BIAS2 Voltage
6
V
IBIAS2
Current Into BIAS2
1
μA
VBIAS(MINOV)
Minimum Voltage to Overdrive INTVCC
Regulator
8.5
V
RFB
Internal Feedback Resistor
499
kΩ
VRUN(RISING)
RUN Enable Voltage (Rising)
1.4
V
VRUN(FALLING)
RUN Enable Voltage (Falling)
1.2
V
fSW
Switching Frequency
100
500
kHz
kHz
RSYNC
SYNC Input Resistance
40
kΩ
VSYNC(TH)
SYNC Voltage Threshold
ISS
Soft-Start Charging Current
No Load
RUN = 0V
RT = 187kΩ
RT = 23.7kΩ
fSYNC = 350kHz
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 RUN pin is internally clamped to 5V
Note 3: The LTM8027E is guaranteed to meet performance specifications
from 0°C to 125°C internal operating temperature. 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 LTM8027I is guaranteed to meet specifications over the full
l
2.3
V
2
μA
–40°C to 125°C internal operating temperature range. The LTM8027MP
is guaranteed to meet specifications over the full –55°C to 125°C
internal operating range. Note that the maximum internal temperature is
determined by specific operating conditions in conjunction with board
layout, the rated package thermal resistance and other environmental
factors.
Note 4: The maximum continuous output current may be derated by the
LTM8027 junction temperature.
Note 5: VIN voltages below the start-up threshold (7.5V) are only
supported when the VCC is externally driven above 6.5V.
8027f
3
LTM8027
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Efficiency vs Load, VOUT = 3.3V
100
90
90
90
80
80
70
70
60
50
40
60
50
40
5VIN
12VIN
24VIN
36VIN
48VIN
60VIN
30
5VIN
12VIN
24VIN
36VIN
20
10
0
0
1
2
LOAD (A)
20
10
0
4
3
0
1
2
LOAD (A)
60
50
40
20
10
0
8027 G03
Efficiency vs Load, VOUT = 12V
Efficiency vs Load, VOUT = 15V
90
90
90
80
80
80
70
70
70
30
10
0
0
1
2
LOAD (A)
50
40
10
0
0
1
2
LOAD (A)
90
80
80
70
70
50
40
30
1
2
LOAD (A)
3
8027 G06
2500
60
50
40
36VIN
48VIN
60VIN
10
8027 G07
4
3
3000
20
4
2
LOAD (A)
1
0
Input Current
vs VIN Output Shorted
30
24VIN
36VIN
48VIN
60VIN
0
0
INPUT CURRENT (mA)
90
EFFICIENCY (%)
100
60
24VIN
36VIN
48VIN
60VIN
10
Efficiency vs Load, VOUT = 24V
100
0
40
8027 G05
Efficiency vs Load, VOUT = 18V
10
50
20
4
3
8027 G04
20
60
30
24VIN
36VIN
48VIN
60VIN
20
4
3
60
30
12VIN
24VIN
36VIN
48VIN
60VIN
20
EFFICIENCY (%)
100
EFFICIENCY (%)
100
40
4
3
8027 G02
Efficiency vs Load, VOUT = 8V
50
2
LOAD (A)
1
0
100
60
12VIN
24VIN
36VIN
48VIN
60VIN
30
4
3
8027 G01
EFFICIENCY (%)
EFFICIENCY (%)
80
70
30
EFFICIENCY (%)
Efficiency vs Load, VOUT = 5V
100
EFFICIENCY (%)
EFFICIENCY (%)
Efficiency vs Load, VOUT = 2.5V
100
0
0
1
2
LOAD (A)
3
2000
1500
1000
500
4
8027 G08
0
0
10
20
30
VIN (V)
40
50
60
8027 G09
8027f
4
LTM8027
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Input Current vs Load,
VOUT = 2.5V
Input Current vs Load,
VOUT = 3.3V
3500
5VIN
12VIN
24VIN
36VIN
3000
INPUT CURRENT (mA)
2500
2000
5VIN
12VIN
24VIN
36VIN
48VIN
60VIN
2000
1500
1000
2500
1600
1500
1000
1000
800
600
400
500
0
0
1
2
LOAD (A)
3
200
0
4
1
2
3
2500
INPUT CURRENT (mA)
1500
1000
3000
24VIN
36VIN
48VIN
60VIN
2000
2000
1500
1000
500
0
2
3
0
4
0
1
2
3
3500
1000
500
0
4
8027 G15
3
15.00
2500
2000
1500
1000
14.50
14.00
13.50
13.00
36VIN
24VIN
12VIN
12.50
0
1
4
15.50
0
3
2
LOAD (A)
Bias Current vs Load,
VOUT = 2.5V
500
2
LOAD (A)
1
8027 G14
BIAS CURRENT (mA)
1500
1
0
36VIN
48VIN
60VIN
3000
2000
0
0
4
8027 G13
INPUT CURRENT (mA)
2500
1000
Input Current vs Load,
VOUT = 24V
24VIN
36VIN
48VIN
60VIN
3000
1500
LOAD (A)
8027 G12
3500
2000
500
LOAD (A)
Input Current vs Load,
VOUT = 18V
4
3
24VIN
36VIN
48VIN
60VIN
2500
500
1
2
LOAD (A)
Input Current vs Load,
VOUT = 15V
INPUT CURRENT (mA)
12VIN
24VIN
36VIN
48VIN
60VIN
0
1
8027 G11
Input Current vs Load,
VOUT = 12V
3500
2500
0
8027 G10
Input Current vs Load,
VOUT = 8V
3000
0
4
LOAD (A)
8027 G43
INPUT CURRENT (mA)
1400
1200
2000
500
0
INPUT CURRENT (mA)
12VIN
24VIN
36VIN
48VIN
60VIN
1800
INPUT CURRENT (mA)
3000
INPUT CURRENT (mA)
Input Current vs Load,
VOUT = 5V
2
LOAD (A)
3
4
12.00
0
1
2
3
4
LOAD (A)
8027 G16
8027 G17
8027f
5
LTM8027
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Bias Current vs Load,
VOUT = 3.3V
Bias Current vs Load,
VOUT = 5V
18.0
Bias Current vs Load,
VOUT = 8V
26.0
16.0
17.5
25.5
16.5
16.0
15.5
15.0
48VIN
36VIN
24VIN
12VIN
14.5
14.0
0
1
2
LOAD (A)
BIAS CURRENT (mA)
17.0
BIAS CURRENT (mA)
BIAS CURRENT (mA)
15.5
15.0
14.5
14.0
13.0
4
3
1
2
0
1
2
3
38
29.0
37
28.5
36
4
LOAD (A)
8027 G20
Bias Current vs Load,
VOUT = 15V
Bias Current vs Load,
VOUT = 18V
45
44
28.0
27.5
27.0
26.5
BIAS CURRENT (mA)
43
BIAS CURRENT (mA)
BIAS CURRENT (mA)
4
3
48VIN
36VIN
24VIN
22.5
8027 G19
29.5
35
34
33
42
41
40
39
38
32
26.0
48VIN
36VIN
24VIN
25.5
0
1
2
30
4
3
0
1
2
3
0
1
42
VIN (V)
38
36
34
48VIN
36VIN
3
6.0
10.0
5.9
9.8
5.8
9.6
5.7
9.4
5.6
9.2
5.5
8.8
5.3
8.6
5.2
8.4
5.1
8.2
LOAD (A)
8027 G44
0
1
2
LOAD (A)
4
9.0
5.4
5.0
4
3
Minimum VIN vs Load,
VOUT = 8V
VIN (V)
44
40
2
LOAD (A)
8027 G23
Minimum VIN vs Load,
VOUT = 5V
46
2
35
4
8027 G22
Bias Current vs Load,
VOUT = 24V
1
48VIN
36VIN
36
LOAD (A)
8027 G21
0
37
48VIN
36VIN
24VIN
31
LOAD (A)
BIAS CURRENT (mA)
23.5
LOAD (A)
Bias Current vs Load,
VOUT = 12V
32
24.0
22.0
0
8027 G18
25.0
24.5
23.0
48VIN
36VIN
24VIN
12VIN
13.5
25.0
3
4
8027 G25
8.0
0
1
2
LOAD (A)
3
4
8027 G26
8027f
6
LTM8027
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Minimum VIN vs Load,
VOUT = 15V
19.0
15.5
18.5
15.0
18.0
14.5
17.5
14.0
16.5
13.0
16.0
12.5
15.5
0
1
2
3
15.0
4
24
23
22
17.0
13.5
12.0
Minimum VIN vs Load,
VOUT = 18V
VIN (V)
16.0
VIN (V)
VIN (V)
Minimum VIN vs Load,
VOUT = 12V
21
20
19
18
0
2
1
LOAD (A)
0
4
3
1
LOAD (A)
8027 G27
2
LOAD (A)
3
8027 G29
8027 G28
Minimum VIN vs Load,
VOUT = 24V
Minimum VIN vs VOUT,
IOUT = 4A
Minimum VIN vs Load,
VOUT = –3.3V
35
9
30
30
8
28
25
26
20
32
4
24
6
VIN (V)
VIN (V)
VIN (V)
7
15
22
10
20
5
18
0
5
4
3
2
0
1
2
3
1
0
4
5
10
15
20
0
25
0
1
VOUT (V)
LOAD (A)
2
3
8027 G31
8027 G30
Minimum VIN vs Load,
VOUT = –5V
8027 G45
Minimum VIN vs Load,
VOUT = –8V
12
30
10
25
8
20
4
LOAD (A)
Minimum VIN vs Load,
VOUT = –12V
50
6
40
35
VIN (V)
VIN (V)
VIN (V)
45
15
30
25
20
4
10
2
5
15
10
5
0
0
1
2
LOAD (A)
3
4
8027 G32
0
0
0
1
2
LOAD (A)
3
4
8027 G33
0
1
2
LOAD (A)
3
4
8027 G34
8027f
7
LTM8027
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Temperature Rise vs Load,
VOUT = 3.3V
36VIN
24VIN
12VIN
5VIN
32
60VIN
48VIN
36VIN
24VIN
12VIN
5VIN
40
TEMPERATURE RISE (°C)
TEMPERATURE RISE (°C)
37
27
22
17
12
7
2
50
45
42
Temperature Rise vs Load,
VOUT = 5V
35
30
25
20
15
10
0
2
1
3
4
0
1
2
0
60VIN
48VIN
36VIN
24VIN
16VIN
30
20
10
60
50
40
30
20
10
0
2
3
0
4
4
60VIN
48VIN
36VIN
24VIN
20.5VIN
80
TEMPERATURE RISE (°C)
70
40
3
Temperature Rise vs Load,
VOUT = 15V
90
80
60VIN
48VIN
36VIN
24VIN
12VIN
70
60
50
40
30
20
10
0
0
1
LOAD (A)
2
4
3
0
2
1
3
4
LOAD (A)
LOAD (A)
8027 G38
8027 G40
8027 G39
Temperature Rise vs Load,
VOUT = 24V
Temperature Rise vs Load,
VOUT = 18V
100
100
60VIN
48VIN
36VIN
26VIN
80
70
60
50
40
30
80
70
60
50
40
30
20
20
10
10
0
0
1
60VIN
48VIN
36VIN
90
TEMPERATURE RISE (°C)
90
TEMPERATURE RISE (°C)
2
LOAD (A)
1
8027 G37
Temperature Rise vs Load,
VOUT = 12V
TEMPERATURE RISE (°C)
TEMPERATURE RISE (°C)
15
8027 G36
70
1
20
LOAD (A)
Temperature Rise vs Load,
VOUT = 8V
0
25
0
4
3
8027 G35
50
35
30
5
LOAD (A)
60
40
10
5
0
60VIN
48VIN
36VIN
24VIN
12VIN
45
TEMPERATURE RISE (°C)
Temperature Rise vs Load,
VOUT = 2.5V
2
LOAD (A)
3
4
8027 G41
0
0
1
2
LOAD (A)
3
4
8027 G42
8027f
8
LTM8027
PIN FUNCTIONS
VIN (Bank 3): The VIN pin supplies current to the LTM8027’s
internal regulator and to the internal power switch. This
pin must be locally bypassed with an external, low ESR
capacitor (see Table 2).
VOUT (Bank 1): Power Output Pins. Apply the output filter
capacitor and the output load between these and the GND
pins.
AUX (Pin A7): Low Current Voltage Source for BIAS1and
BIAS2. In many designs, the BIAS pins are simply connected
to VOUT. The AUX pin is internally connected to VOUT and
is placed near the BIAS pins to ease printed circuit board
routing. Although this pin is internally connected to VOUT,
do NOT connect this pin to the load. If this pin is not tied
to BIAS1 and BIAS2, leave it floating.
BIAS1 (Pin A6): The BIAS1 pin connects to the internal
power bus. Connect to a power source greater than 8.5V.
If the output is greater than 8.5V, connect it to this pin. If
the output voltage is less, connect this to a voltage source
between 8.5V and 15V. For proper operation, connect this
pin to the same power source as BIAS2.
BIAS2 (Pin A3): Internal Biasing Power. This pin must be
connected to the same power source as BIAS1 for proper
operation. Always connect this pin to a voltage source
above 8.5V. Do not leave BIAS2 floating.
RUN (Pin A4): Tie the RUN pin to ground to shut down the
LTM8027. Tie to 1.4V or more for normal operation. The
RUN pin is internally clamped to 5V, so when it is pulled
up, be sure to use a pull-up resistor that limits the current in to the RUN pin to less than 1mA. If the shutdown
feature is not used, tie this pin to the VIN pin through a
pull-up resistor.
GND (Bank 2): Tie these GND pins to a local ground plane
below the LTM8027 and the circuit components.
RT (Pin B1): The RT pin is used to program the switching
frequency of the LTM8027 by connecting a resistor from
this pin to ground. The Applications Information section of
the data sheet includes a table to determine the resistance
value based on the desired switching frequency. Minimize
capacitance at this pin.
SYNC (Pin C1): The SYNC pin provides an external clock
input for synchronization of the internal oscillator. The
RT resistor should be set such that the internal oscillator frequency is 10% to 25% below the external clock
frequency. If unused, the SYNC pin is connected to GND.
For more information see Oscillator Sync in the Application
Information section of this data sheet.
ADJ (Pin A2): The LTM8027 regulates its ADJ pin to 1.23V.
Connect the adjust resistor from this pin to ground. The
value of RADJ is given by the equation:
RADJ = 613.77/(VOUT – 1.23)
where RADJ is in kΩ.
SS (Pin A5): The soft-start pin is used to program the
supply soft-start function. Use the following formula to
calculate CSS for a given output voltage slew rate:
CSS = 2μA(tSS/1.231V)
The pin should be left unconnected when not using the
soft-start function.
8027f
9
LTM8027
BLOCK DIAGRAM
VIN
VOUT
6.8μH
499k
4.7pF
2.2μF
RUN
SS
INTERNAL
CONNECTION
TO VOUT
CURRENT
MODE
CONTROLLER
SYNC
VIN
INTERNAL
LINEAR
REGULATOR
AUX
BIAS1
INTVCC
BIAS2
GND
RT
ADJ
8027 BD
OPERATION
The LTM8027 is a standalone nonisolated step-down
switching DC/DC power supply with an input voltage
range of 4.5V to 60V that can deliver up to 4A of output
current. This module provides a precisely regulated output
voltage up to 24V, programmable via one external resistor.
Given that the LTM8027 is a step-down converter, make
sure that the input voltage is high enough to support the
desired output voltage and load current. A simplified block
diagram is given above. The LTM8027 contains a current
mode controller, power switching element, power inductor, power MOSFETs and a modest amount of input and
output capacitance.
The LTM8027 is a fixed frequency PWM regulator. The
switching frequency is set by simply connecting the appropriate resistor from the RT pin to GND.
A linear regulator provides internal power (shown as
INTVCC on the Block Diagram) to the control circuitry. The
bias regulator normally draws power from the VIN pin, but
if the BIAS1and BIAS2 pins are connected to an external
voltage higher than 8.5V, bias power will be drawn from
the external source (typically the regulated output voltage).
This improves efficiency. The RUN pin is used to enable
or place the LTM8027 in shutdown, disconnecting the
output and reducing the input current to less than 10μA.
8027f
10
LTM8027
APPLICATIONS INFORMATION
For most applications, the design process is straight
forward, summarized as follows:
1. Look at Table 2 and find the row that has the desired
input range and output voltage.
2. Apply the recommended CIN, COUT, RADJ and RT values.
3. Connect the BIAS pins as indicated.
While these component and connection combinations have
been tested for proper operation, it is incumbent upon the
user to verify proper operation over the intended system’s
line, load and environmental conditions.
Capacitor Selection Considerations
The CIN and COUT capacitor values in Table 2 are the
minimum recommended values for the associated operating conditions. Applying capacitor values below those
indicated in Table 2 is not recommended, and may result
in undesirable operation. Using larger values is generally
acceptable, and can yield improved dynamic response, if
it is necessary. Again, it is incumbent upon the user to
verify proper operation over the intended system’s line,
load and environmental conditions.
Ceramic capacitors are small, robust and have very low
ESR. However, not all ceramic capacitors are suitable.
X5R and X7R types are stable over temperature and applied voltage and give dependable service. Other types,
including Y5V and Z5U have very large temperature and
voltage coefficients of capacitance. In an application circuit they may have only a small fraction of their nominal
capacitance resulting in much higher output voltage ripple
than expected.
Ceramic capacitors are also piezoelectric. The LTM8027’s
switching frequency depends on the load current, and
at light loads it can excite a ceramic capacitor at audio
frequencies, generating audible noise.
A final precaution regarding ceramic capacitors concerns
the maximum input voltage rating of the LTM8027. A
ceramic input capacitor combined with trace or cable
inductance forms a high Q (under damped) tank circuit.
If the LTM8027 circuit is plugged into a live supply, the
input voltage can ring to twice its nominal value, possibly exceeding the device’s rating. This situation is easily
avoided; see the Hot-Plugging Safely section.
Input Power Requirements
The LTM8027 is biased using an internal linear regulator to generate operational voltages from the VIN pin.
Virtually all of the circuitry in the LTM8027 is biased via
this internal linear regulator output (INTVCC). This pin is
internally decoupled with a low ESR capacitor to GND.
The VCC regulator generates an 8V output provided there
is ample voltage on the VIN pin. The VCC regulator has
approximately 1V of dropout, and will follow the VIN pin
with voltages below the dropout threshold.
The LTM8027 has a typical start-up requirement of VIN >
7.5V. This assures that the onboard regulator has ample
headroom to bring INTVCC above its UVLO threshold.
The INTVCC regulator can only source current, so forcing
the BIAS pin above 8.5V allows use of externally derived
power for the IC. This effectively shuts down the internal
linear regulator and reduces power dissipation within the
LTM8027. Using the onboard regulator for start-up, then
deriving power for VCC from the converter output maximizes conversion efficiencies and is common practice. If
VCC is maintained above 6.5V using an external source, the
LTM8027 can continue to operate with VIN as low as 4V.
BIAS Power
The internal circuitry of the LTM8027 is powered by the
INTVCC bus, which is derived either from the afore mentioned internal linear regulator or the BIAS1 and BIAS2
pins, if it is greater than 8.5V. Since the internal linear
regulator is by nature dissipative, deriving INTVCC from
an external source through the BIAS pins reduces the
power lost within the LTM8027 and can increase overall
system efficiency.
8027f
11
LTM8027
APPLICATIONS INFORMATION
For example, suppose the LTM8027 needs to provide 5V
from an input voltage source that is nominally 12V. From
Table 2, the recommended RT value is 162k, which corresponds to an operating frequency of 210kHz. From the
graphs in the Typical Performance Characteristics, the
typical INTVCC current at 12VIN and 210kHz is 15mA. The
power dissipated by the internal linear regulator at 12VIN
is given by the equation:
Operating Frequency Tradeoffs
The LTM8027 uses a constant frequency architecture that
can be programmed over a 100kHz to 500kHz range with
a single resistor from the RT pin to ground. The nominal
voltage on the RT pin is 1V and the current that flows from
this pin is used to charge an internal oscillator capacitor.
The value of RT for a given operating frequency can be
chosen from Figure 1 or Table 1.
PINTVCC = (VIN – 8.5) • IINTVCC
600
or only 54mW. This has a small but probably acceptable
effect on the operating temperature of the LTM8027.
Soft-Start
The soft-start function controls the slew rate of the power
supply output voltage during start-up. A controlled output
voltage ramp minimizes output voltage overshoot, reduces
inrush current from the VIN supply, and facilitates supply
sequencing. A capacitor connected from the SS pin to GND
programs the slew rate. The capacitor is charged from an
internal 2μA current source producing a ramped voltage
that overrides the command reference to the controller,
resulting in a smooth output voltage ramp. The soft-start
circuit is disabled once the SS pin voltage has been charged
to 200mV above the internal reference of 1.231V.
During a VIN UVLO, INTVCC undervoltage or RUN event,
the SS pin voltage is discharged with a 50μA. Therefore,
the value of the SS capacitor determines how long one
of these events must be in order to completely discharge
the soft-start capacitor. In the case of an output overload
or short circuit, the SS pin voltage is clamped to a diode
drop above the ADJ pin. Once the short has been removed
the VADJ pin voltage starts to recover. The soft-start circuit
takes control of the output voltage slew rate once the
VADJ pin voltage has exceeded the slowly ramping SS pin
voltage, reducing the output voltage overshoot during a
short-circuit recovery.
FREQUENCY (kHz)
If the input rises to 60V, however, the power dissipation is
a lot higher, over 750mW. This can cause unnecessarily
high junction temperatures if the INTVCC regulator must
dissipate this amount of power for very long.
500
400
300
200
100
0
0
50
100
RT (kΩ)
150
200
8027 F01
Figure 1. Timing Resistor (RT) Value
Table 1 lists typical resistor values for common operating
frequencies.
Table 1. RT Resistor Values vs Frequency
RT (kΩ)
fSW (kHz)
187
100
118
150
82.5
200
63.4k
250
48.7k
300
40.2k
350
31.6k
400
27.4k
450
23.7k
500
8027f
12
LTM8027
APPLICATIONS INFORMATION
It is recommended that the user apply the RT value given
in Table 2 for the input and output operating condition.
System level or other considerations, however, may necessitate another operating frequency. While the LTM8027
is flexible enough to accommodate a wide range of operating frequencies, a haphazardly chosen one may result
in undesirable operation under certain operating or fault
conditions. A frequency that is too high can damage the
LTM8027 if the output is overloaded or short circuited.
A frequency that is too low can result in a final design
that has too much output ripple or too large of an output
capacitor.
The maximum frequency (fMAX) at which the LTM8027
should be allowed to switch and the minimum frequency
set resistor value that should be used for a given set of
input and output operating condition is given in Table 2
as RT(MIN). There are additional conditions that must be
satisfied if the synchronization function is used. Please
refer to the Synchronization section for details.
Output Voltage Programming
The LTM8027 regulates its ADJ pin to 1.23V. Connect the
adjust resistor from this pin to ground. The value of RADJ
is given by the equation RADJ = 613.77/(VOUT – 1.23),
where RADJ is in kΩ.
RUN Control
The LTM8027 RUN pin uses a reference threshold of
1.4V. This precision threshold allows use of the RUN pin
for both logic-level controlled applications and analog
monitoring applications such as power supply sequencing.
The LTM8027 operational status is primarily controlled
by a UVLO circuit on internal power source. When the
LTM8027 is enabled via the RUN pin, only the VCC regulator is enabled. Switching remains disabled until the UVLO
threshold is achieved at the VCC pin, when the remainder
of the LTM8027 is enabled and switching commences.
Because the LTM8027 high power converter is a power
transfer device, a voltage that is lower than expected on
the input supply could require currents that exceed the
sourcing capabilities of that supply, causing the system
to lock up in an undervoltage state. Input supply startup protection can be achieved by enabling the RUN pin
using a resistive divider from the VIN supply to ground.
Setting the divider output to 1.4V when that supply is at
an adequate voltage prevents an LTM8027 converter from
drawing large currents until the input supply is able to
provide the required power. 200mV of input hysteresis on
the RUN pin allows for about 15% of input supply droop
before disabling the converter.
Input UVLO and RUN
The RUN pin has a precision voltage threshold with hysteresis which can be used as an undervoltage lockout
threshold (UVLO) for the power supply. Undervoltage
lockout keeps the LTM8027 in shutdown until the supply
input voltage is above a certain voltage programmed by
the user. The hysteresis voltage prevents noise from falsely
tripping UVLO. Resistors are chosen by first selecting RB
(refer to Figure 2). Then:
⎛ VIN(ON) ⎞
RA = RB • ⎜
– 1⎟
⎝ 1.4V
⎠
where VIN(ON) is the input voltage at which the undervoltage
lockout is disabled and the supply turns on.
VSUPPLY
RA
RUN PIN
RB
8027 F02
Figure 2. Undervoltage Lockout Resistive Divider
8027f
13
LTM8027
APPLICATIONS INFORMATION
Example: Select RB = 49.9k, VIN(ON) = 14.5V (based upon
a 15V minimum input voltage)
⎛ 14.5V ⎞
RA = 49.9k • ⎜
– 1⎟ = 464k
⎝ 1.4V
⎠
The VIN turn off voltage is 15% below turn on. In the example the VIN(OFF) would be 12.3V. The shutdown function
can be disabled by connecting the RUN pin to the VIN pin
through a large value pull-up resistor. This pin contains
a low impedance clamp at 6V, so the RUN pin will sink
current from the pull-up resistor (RPU):
IRUN =
VIN – 6V
RPU
Because this arrangement will clamp the RUN pin to 6V,
it will violate the 5V absolute maximum voltage rating of
the pin. This is permitted, however, as long as the absolute
maximum input current rating of 1mA is not exceeded.
Input RUN pin currents of <100μA are recommended: a
1M or greater pull-up resistor is typically used for this
configuration.
Soft-Start
The desired soft-start time (tSS) is programmed via the
CSS capacitor as follows:
CSS =
2µA • tSS
1.231V
The amount of time in which the power supply must be
under a VIN, VCC or VSHDN UVLO fault condition (tFAULT)
before the SS pin voltage enters its active region is approximated by the following formula:
tFAULT =
CSS • 0.65V
50µA
Hot-Plugging Safely
The small size, robustness and low impedance of ceramic
capacitors make them an attractive option for the input
bypass capacitor of LTM8027. However, these capacitors
can cause problems if the LTM8027 is plugged into a live
supply (see Linear Technology Application Note 88 for
a complete discussion). The low loss ceramic capacitor
combined with stray inductance in series with the power
source forms an under damped tank circuit, and the voltage at the VIN pin of the LTM8027 can ring to twice the
nominal input voltage, possibly exceeding the LTM8027’s
rating and damaging the part. If the input supply is poorly
controlled or the user will be plugging the LTM8027 into an
energized supply, the input network should be designed to
prevent this overshoot by introducing a damping element
into the path of current flow. This is often done by adding
an inexpensive electrolytic bulk capacitor across the input
terminals of the LTM8027. The criteria for selecting this
capacitor is that the ESR is high enough to damp the ringing,
and the capacitance value is several times larger than the
LTM8027 ceramic input capacitor. The bulk capacitor does
not need to be located physically close to the LTM8027;
it should be located close to the application board’s input
connector, instead.
Synchronization
The oscillator can be synchronized to an external clock.
Choose the RT resistor such that the resultant frequency is
at least 10% below the desired synchronization frequency.
It is recommended that the SYNC pin be driven with a
square wave that has amplitude greater than 2.3V, pulse
width greater than 1μs and rise time less than 500ns. The
rising edge of the sync wave form triggers the discharge
of the internal oscillator capacitor.
8027f
14
LTM8027
APPLICATIONS INFORMATION
PCB Layout
Most of the headaches associated with PCB layout have
been alleviated or even eliminated by the high level of
integration of the LTM8027. The LTM8027 is nevertheless a switching power supply, and care must be taken to
minimize EMI and ensure proper operation. Even with the
high level of integration, you may fail to achieve specified
operation with a haphazard or poor layout. See Figure 3
for a suggested layout.
Ensure that the grounding and heatsinking are acceptable.
A few rules to keep in mind are:
1. Place the RADJ and RT resistors as close as possible to
their respective pins.
2. Place the CIN capacitor as close as possible to the VIN
and GND connection of the LTM8027.
3. Place the COUT capacitor as close as possible to the
VOUT and GND connection of the LTM8027.
4. Place the CIN and COUT capacitors such that their
ground current flow directly adjacent to or underneath
the LTM8027.
5. Connect all of the GND connections to as large a copper
pour or plane area as possible on the top layer. Avoid
breaking the ground connection between the external
components and the LTM8027.
Use vias to connect the GND copper area to the board’s
internal ground planes. Liberally distribute these GND vias
to provide both a good ground connection and thermal
path to the internal planes of the printed circuit board. Pay
attention to the location and density of the thermal vias in
Figure 3. The LTM8027 can benefit from the heat sinking
afforded by vias that connect to internal GND planes at
these locations, due to their proximity to internal power
handling components. The optimum number of thermal
vias depends upon the printed circuit board design. For
example, a board might use very small via holes. It should
employ more thermal vias than a board that uses larger
holes.
Thermal Considerations
The LTM8027 output current may need to be derated if it is
required to operate in a high ambient temperature or deliver
a large amount of continuous power. The amount of current
derating is dependent upon the input voltage, output power
and ambient temperature. The temperature rise curves
given in the Typical Performance Characteristics section
can be used as a guide. These curves were generated by a
LTM8027 mounted to a 58cm2 4-layer FR4 printed circuit
board. Boards of other sizes and layer count can exhibit
different thermal behavior, so it is incumbent upon the user
to verify proper operation over the intended system’s line,
load and environmental operating conditions.
VOUT
COUT
COUT
GND
AUX
BIAS1
SS
RUN
CIN
BIAS2
VIN
RADJ
RT
GND
SYNC
8027 F03
Figure 3. Suggested Layout
8027f
15
LTM8027
APPLICATIONS INFORMATION
The junction-to-air and junction-to-board thermal resistances given in the Pin Configuration diagram may also
be used to estimate the LTM8027 internal temperature.
These thermal coefficients are determined per JESD 51-9
(JEDEC standard, test boards for area array surface mount
package thermal measurements) through analysis and
physical correlation. Bear in mind that the actual thermal
resistance of the LTM8027 to the printed circuit board
depends upon the design of the circuit board.
The die temperature of the LTM8027 must be lower than
the maximum rating of 125°C, so care should be taken in
the layout of the circuit to ensure good heat sinking of the
LTM8027. The bulk of the heat flow out of the LTM8027
is through the bottom of the module and the LGA pads
into the printed circuit board. Consequently a poor printed
circuit board design can cause excessive heating, resulting in impaired performance or reliability. Please refer to
the PCB Layout section for printed circuit board design
suggestions.
Table 2. Recommended Component Values and Configuration
(TA = 25°C. See Typical Performance Characteristics for load Conditions)
VIN RANGE
(V)
VOUT
(V)
BIAS1/BIAS2
RADJ
(kΩ)
fOPTIMAL
(kHz)
ROPTIMAL
(kΩ)
fMAX
(kHz)
RMAX
(kΩ)
4.5 to 60
3.3
2 × 4.7μF 2220 100V 5 × 100μF 1812 6.3V
8.5V to 15V
301
115
154
160
107
7.5 to 60
5
2 × 4.7μF 2220 100V 4 × 100μF 1210 6.3V
8.5V to 15V
162
210
75.0
230
68.2
10.5 to 60
8
2 × 4.7μF 2220 100V
4 × 47μF 1210 10V
8.5V to 15V
90.9
260
59.0
350
40.2
CIN
COUT
16 to 60
12
2 × 4.7μF 2220 100V
4 × 22μF 1210 16V
AUX
56.2
300
48.7
500
23.7
20.5 to 60
15
2 × 4.7μF 2220 100V
4 × 22μF 1210 16V
AUX
44.2
350
40.2
500
23.7
26 to 60
18
2 × 4.7μF 2220 100V
4 × 10μF 1812 25V
8.5V to 15V
36.5
400
31.6
500
23.7
34 to 60
24
2 × 4.7μF 2220 100V
4 × 10μF 1812 25V
8.5V to 15V
26.7
430
28.7
500
23.7
4.5 to 40
2.5
2 × 10μF 2220 50V
5 × 100μF 1812 6.3V
8.5V to 15V
487
145
124
185
88.7
4.5 to 40
3.3
2 × 10μF 2220 50V
4 × 100μF 1812 6.3V
8.5V to 15V
301
165
102
240
64.9
7.5 to 40
5
2 × 10μF 2220 50V
4 × 100μF 1210 6.3V
8.5V to 15V
162
210
75.0
315
45.3
10.5 to 40
8
2 × 10μF 2220 50V
4 × 47μF 1210 10V
8.5V to 15V
90.9
260
59.0
500
23.7
16 to 40
12
2 × 10μF 2220 50V
4 × 22μF 1210 16V
AUX
56.2
300
48.7
500
23.7
20.5 to 40
15
1 × 10μF 2220 50V
4 × 22μF 1210 16V
AUX
44.2
350
40.2
500
23.7
26 to 40
18
1 × 10μF 2220 50V
4 × 10μF 1812 25V
8.5V to 15V
36.5
400
31.6
500
23.7
34 to 40
24
1 × 10μF 2220 50V
4 × 10μF 1812 25V
8.5V to 15V
26.7
430
28.7
500
23.7
4.5 to 56
–3.3
301
115
154
155
115
2 × 4.7μF 2220 100V 5 × 100μF 1812 6.3V 8.5V to 15V Above Output
4.5 to 55
–5
2 × 4.7μF 2220 100V 4 × 100μF 1210 6.3V 8.5V to 15V Above Output
162
190
90.9
230
68.2
10.5 to 52
–8
2 × 4.7μF 2220 100V
4 × 47μF 1210 10V
8.5V to 15V Above Output
90.9
260
59.0
350
40.2
16 to 48
–12
2 × 4.7μF 2220 100V
4 × 22μF 1210 16V
AUX
56.2
300
48.7
500
23.7
8027f
16
LTM8027
TYPICAL APPLICATIONS
5V VOUT Step-Down Converter
3.3V VOUT Step-Down Converter
VIN*
4.5V TO 40V
10μF
s2
VIN
VOUT
3.3V
4A
VOUT
1M
LTM8027
RUN
BIAS1
SS
BIAS2
RT
301k
4.7μF
s2
1M
ADJ
GND
162k
3845 TA03
VOUT
15V
3.5A
4A SURGE
VIN
26V TO 60V
VIN
4.7μF
s2
1M
LTM8027
BIAS1
RUN
BIAS1
SS
BIAS2
SS
BIAS2
22μF
s4
AUX
RT
44.2k
31.6k
3845 TA04
9V
10μF
s4
AUX
SYNC
ADJ
VOUT
18V
3A
4A SURGE
VOUT
RUN
GND
100μF
s4
AUX
18V VOUT Step-Down Converter
LTM8027
RT
9V
3845 TA02
VOUT
SYNC
40.2k
BIAS2
75k
15V VOUT Step-Down Converter
VIN
BIAS1
SS
RT
*RUNNING VOLTAGE. SEE APPLICATIONS
INFORMATION FOR START-UP DETAILS
VIN
20.5V TO 60V
LTM8027
RUN
SYNC
ADJ
VOUT
5V
4A
VOUT
1M
100μF
s4
GND
102k
VIN
4.7μF
s2
9V
AUX
SYNC
VIN
7.5V TO 60V
ADJ
GND
36.5k
3845 TA05
–12V VOUT Postitive-to-Negative Converter
VIN
20V TO 48V
4.7μF
s2
VIN
1M
VOUT
LTM8027
RUN
BIAS1
SS
BIAS2
RT
48.7k
22μF
s4
AUX
SYNC
ADJ
GND
56.2k
3845 TA07
VOUT
–12V
3A
8027f
17
4
PACKAGE TOP VIEW
15
BSC
2.540
2.540
SUGGESTED PCB LAYOUT
TOP VIEW
3.810
3.810
5.080
6.350
15
BSC
Y
DETAIL A
0.27 – 0.37
SUBSTRATE
eee S X Y
DETAIL B
0.635 p0.025 SQ. 113x
aaa Z
3.95 – 4.05
MOLD
CAP
DETAIL B
4.22 – 4.42
6.350
5.080
3.810
2.540
1.270
DETAILS OF PAD #1 IDENTIFIER ARE OPTIONAL,
BUT MUST BE LOCATED WITHIN THE ZONE INDICATED.
THE PAD #1 IDENTIFIER MAY BE EITHER A MOLD OR
MARKED FEATURE
4
SYMBOL TOLERANCE
aaa
0.15
bbb
0.10
eee
0.05
6. THE TOTAL NUMBER OF PADS: 113
5. PRIMARY DATUM -Z- IS SEATING PLANE
LAND DESIGNATION PER JESD MO-222, SPP-010
3
1.27
BSC
12.70
BSC
3
L
TRAY PIN 1
BEVEL
COMPONENT
PIN “A1”
PADS
SEE NOTES
2. ALL DIMENSIONS ARE IN MILLIMETERS
5.080
0.000
6.350
NOTES:
1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M-1994
X
// bbb Z
1.270
2.540
3.810
5.080
6.350
PAD 1
CORNER
1.270
aaa Z
0.000
(Reference LTC DWG # 05-08-1756 Rev Ø)
Z
18
1.270
LGA Package
113-Lead (15mm × 15mm × 4.32mm)
K
J
G
F
E
D
C
B
LGA 113 0807 REV Ø
A
DETAIL A
PACKAGE IN TRAY LOADING ORIENTATION
LTMXXXXXX
MModule
PACKAGE BOTTOM VIEW
H
12.70
BSC
1
2
3
4
5
6
7
8
9
C(0.30)
PAD 1
10
11
LTM8027
PACKAGE DESCRIPTION
8027f
LTM8027
PACKAGE DESCRIPTION
Pin Assignment Table
(Arranged by Pin Number)
PIN NAME
PIN NAME
PIN NAME
A1
GND
D6
GND
H5
GND
A2
ADJ
D7
GND
H6
GND
A3
BIAS2
D8
GND
H7
GND
A4
RUN
D9
GND
H8
GND
A5
SS
D10
GND
H9
VOUT
A6
BIAS1
D11
GND
H10
VOUT
A7
AUX
E1
GND
H11
VOUT
A8
GND
E2
GND
J1
VIN
A9
GND
E3
GND
J2
VIN
A10
GND
E4
GND
J3
VIN
A11
GND
E5
GND
J5
GND
B1
RT
E6
GND
J6
GND
B2
GND
E7
GND
J7
GND
B3
GND
E8
GND
J8
GND
B4
GND
E9
VOUT
J9
VOUT
B5
GND
E10
VOUT
J10
VOUT
B6
GND
E11
VOUT
J11
VOUT
B7
GND
F1
GND
K1
VIN
B8
GND
F2
GND
K2
VIN
B9
GND
F3
GND
K3
VIN
B10
GND
F4
GND
K5
GND
B11
GND
F5
GND
K6
GND
C1
SYNC
F6
GND
K7
GND
C2
GND
F7
GND
K8
GND
C3
GND
F8
GND
K9
VOUT
C4
GND
F9
VOUT
K10
VOUT
C5
GND
F10
VOUT
K11
VOUT
C6
GND
F11
VOUT
L1
VIN
C7
GND
G5
GND
L2
VIN
C8
GND
G6
GND
L3
VIN
C9
GND
G7
GND
L5
GND
C10
GND
G8
GND
L6
GND
C11
GND
G9
VOUT
L7
GND
D1
GND
G10
VOUT
L8
GND
D2
GND
G11
VOUT
L9
VOUT
D3
GND
H1
VIN
L10
VOUT
D4
GND
H2
VIN
L11
VOUT
D5
GND
H3
VIN
8027f
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
19
LTM8027
PACKAGE PHOTOGRAPH
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTM4600
10A DC/DC μModule Regulator
Basic 10A DC/DC μModule, 15mm × 15mm × 2.8mm LGA
LTM4600HVMPV
Military Plastic 10A DC/DC μModule Regulator
–55°C to 125°C Operation, 15mm × 15mm × 2.8mm LGA
LTM4601/
LTM4601A
12A DC/DC μModule with PLL, Output Tracking/
Margining and Remote Sensing
Synchronizable, PolyPhase Operation, LTM4601-1 Version has no Remote
Sensing
LTM4602
6A DC/DC μModule Regulator
Pin Compatible with the LTM4600
LTM4603
6A DC/DC μModule with PLL and Output Tracking/
Margining and Remote Sensing
Synchronizable, PolyPhase Operation, LTM4603-1 Version has no Remote
Sensing, Pin Compatible with the LTM4601
LTM4604
4A Low VIN DC/DC μModule Regulator
2.375V ≤ VIN ≤ 5V, 0.8V ≤ VOUT ≤ 5V, 9mm × 15mm × 2.3mm LGA
LTM4608
8A Low VIN DC/DC μModule Regulator
2.375V ≤ VIN ≤ 5V, 0.8V ≤ VOUT ≤ 5V, 9mm × 15mm × 2.8mm LGA
LTM8020
200mA, 36V DC/DC μModule Regulator
Fixed 450kHz Frequency, 1.25V ≤ VOUT ≤ 5V, 6.25mm × 6.25mm × 2.32mm LGA
LTM8022
1A, 36V DC/DC μModule Regulator
Adjustable Frequency, 0.8V ≤ VOUT ≤ 5V, 11.25mm × 9mm × 2.82mm LGA,
Pin Compatible to the LTM8023
LTM8023
2A, 36V DC/DC μModule Regulator
Adjustable Frequency, 0.8V ≤ VOUT ≤ 5V, 11.25mm × 9mm × 2.82mm LGA,
Pin Compatible to the LTM8022
LTM8025
3A, 36V DC/DC μModule Regulator
0.8V ≤ VOUT ≤ 24V, 9mm × 15mm × 4.32mm LGA
8027f
20 Linear Technology Corporation
LT 1009 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
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© LINEAR TECHNOLOGY CORPORATION 2009
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