regulator with internal power switch that draws only 12μA
typical DC supply current while maintaining a regulated
output voltage at no load.
The LTC7138 can supply up to 400mA load current and
features a programmable peak current limit that provides
a simple method for optimizing efficiency and for reduc-
ing output ripple and component size. The LTC7138’s
combination of Burst Mode
®
operation, integrated power
switch, low quiescent current, and programmable peak
current limit provides high efficiency over a broad range
of load currents.
With its wide input range of 4V to 140V and programmable
overvoltage lockout, the LTC7138 is a robust regulator
suited for regulating from a wide variety of power sources.
Additionally, the LTC7138 includes a precise run threshold
and soft-start feature to guarantee that the power system
start-up is well-controlled in any environment. A feedback
comparator output enables multiple LTC7138s to be con-
nected in parallel for higher current applications.
The LTC7138 is available in a thermally enhanced high
voltage-capable 16-lead MSE package with four missing pins.
L,
LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
n
n
n
n
n
n
n
n
n
n
Wide Operating Input Voltage Range: 4V to 140V
Internal Low Resistance Power MOSFET
No Compensation Required
Adjustable 100mA to 400mA Maximum Output
Current
Low Dropout Operation: 100% Duty Cycle
Low Quiescent Current: 12µA
Wide Output Range: 0.8V to V
IN
0.8V ±1% Feedback Voltage Reference
Precise RUN Pin Threshold
Internal or External Soft-Start
Programmable 1.8V, 3.3V, 5V or Adjustable Output
Few External Components Required
Programmable Input Overvoltage Lockout
Thermally Enhanced High Voltage MSOP Package
applicaTions
n
n
n
n
n
n
n
Industrial Control Supplies
Medical Devices
Distributed Power Systems
Portable Instruments
Battery-Operated Devices
Avionics
Automotive
Typical applicaTion
5V to 140V Input to 5V Output, 400mA Step-Down Regulator
V
IN
5V TO 140V C
IN
1µF
250V
L1
220µH
V
IN
LTC7138
ANODE
RUN
SS
V
PRG1
V
FB
OVLO
V
PRG2
GND
SW
V
OUT
5V
C
OUT
400mA
22µF
Efficiency and Power Loss vs Load Current
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
7138 TA01a
EFFICIENCY
POWER LOSS (mW)
1000
100
10
POWER LOSS
10
0
0.1
1
V
IN
= 12V
V
IN
= 48V
V
IN
= 140V
10
100
LOAD CURRENT (mA)
1
1000
7138f
7138 TA01b
For more information
www.linear.com/LTC7138
1
LTC7138
absoluTe MaxiMuM raTings
(Note 1)
pin conFiguraTion
TOP VIEW
SW 1
V
IN
3
FBO
V
PRG2
V
PRG1
GND
5
6
7
8
17
GND
16 ANODE
14 RUN
12
11
10
9
OVLO
I
SET
SS
V
FB
V
IN
Supply Voltage ................................... –0.3V to 140V
RUN Voltage............................................. –0.3V to 140V
SS, FBO, OVLO, I
SET
Voltages ...................... –0.3V to 6V
V
FB
, V
PRG1
, V
PRG2
Voltages ......................... –0.3V to 6V
Operating Junction Temperature Range (Notes 2, 3, 4)
LTC7138E, LTC7138I .......................... –40°C to 125°C
LTC7138H .......................................... –40°C to 150°C
LTC7138MP ....................................... –55°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................... 300°C
MSE PACKAGE
VARIATION: MSE16 (12)
16-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 40°C/W,
θ
JC
= 10°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH
LTC7138EMSE#PBF
LTC7138IMSE#PBF
LTC7138HMSE#PBF
LTC7138MPMSE#PBF
TAPE AND REEL
LTC7138EMSE#TRPBF
LTC7138IMSE#TRPBF
LTC7138HMSE#TRPBF
LTC7138MPMSE#TRPBF
PART MARKING*
7138
7138
7138
7138
PACKAGE DESCRIPTION
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–55°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
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/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
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
V
IN
V
OUT
UVLO
PARAMETER
Input Voltage Operating Range
Output Voltage Operating Range
V
IN
Undervoltage Lockout
DC Supply Current (Note 5)
Active Mode
Sleep Mode
Shutdown Mode
RUN Pin Threshold
V
IN
Rising
V
IN
Falling
Hysteresis
l
l
elecTrical characTerisTics
CONDITIONS
MIN
4
0.8
3.5
3.3
TYP
MAX
140
V
IN
UNITS
V
V
V
V
mV
µA
µA
µA
V
V
mV
nA
V
V
mV
7138f
Input Supply (V
IN
)
3.75
3.5
250
200
12
1.4
4.0
3.8
I
Q
No Load
V
RUN
= 0V
RUN Rising
RUN Falling
Hysteresis
RUN = 1.3V
OVLO Rising
OVLO Falling
Hysteresis
1.17
1.06
–10
1.17
1.06
400
22
6
1.25
1.14
10
1.25
1.14
V
RUN
I
RUN
V
OVLO
1.21
1.10
110
0
1.21
1.10
110
RUN Pin Leakage Current
OVLO Pin Threshold
2
For more information
www.linear.com/LTC7138
LTC7138
elecTrical characTerisTics
SYMBOL
V
FB(ADJ)
V
FBH
I
FB
V
FB(FIXED)
PARAMETER
Feedback Comparator Threshold
(Adjustable Output)
Feedback Comparator Hysteresis
(Adjustable Output)
Feedback Pin Current
Feedback Comparator Thresholds
(Fixed Output)
Output Supply (V
FB
)
V
FB
Rising, V
PRG1
= V
PRG2
= 0V
LTC7138E, LTC7138I
LTC7138H, LTC7138MP
V
FB
Falling, V
PRG1
= V
PRG2
= 0V
V
FB
= 1V, V
PRG1
= V
PRG2
= 0V
V
FB
Rising, V
PRG1
= SS, V
PRG2
= 0V
V
FB
Falling, V
PRG1
= SS, V
PRG2
= 0V
V
FB
Rising, V
PRG1
= 0V, V
PRG2
= SS
V
FB
Falling, V
PRG1
= 0V, V
PRG2
= SS
V
FB
Rising, V
PRG1
= V
PRG2
= SS
V
FB
Falling, V
PRG1
= V
PRG2
= SS
Operation
I
PEAK
I
VAL
R
ON
I
LSW
I
SS
t
INT(SS)
Peak Current Comparator Threshold
I
SET
Floating
100k Resistor from I
SET
to GND
I
SET
Shorted to GND
I
SET
Floating
100k Resistor from I
SET
to GND
I
SET
Shorted to GND
I
SW
= –100mA
V
IN
= 140V, SW = 0V
V
SS
< 2.5V
SS Pin Floating
4
l
l
l
l
l
l
l
l
l
l
l
l
l
l
l
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.
CONDITIONS
MIN
TYP
MAX
UNITS
0.792
0.788
3
–10
4.94
4.91
3.25
3.23
1.78
1.77
540
270
140
50
45
45
0.800
0.800
5
0
5.015
4.985
3.31
3.29
1.81
1.80
610
310
170
60
60
60
1.8
0.1
5
1
0.808
0.812
9
10
5.09
5.06
3.37
3.35
1.84
1.83
680
350
200
70
70
75
1
6
V
V
mV
nA
V
V
V
V
V
V
mA
mA
mA
%
%
%
Ω
μA
μA
ms
Valley Current Comparator Threshold
Relative to I
PEAK
Power Switch On-Resistance
Switch Pin Leakage Current
Soft-Start Pin Pull-Up Current
Internal Soft-Start Time
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 LTC7138 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC7138E is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 125°C operating
junction temperature range are assured by design, characterization and
correlation with statistical process controls. The LTC7138I is guaranteed
over the –40°C to 125°C operating junction temperature range, the
LTC7138H is guaranteed over the –40°C to 150°C operating junction
temperature range and the LTC7138MP is tested and guaranteed over the
–55°C to 150°C operating junction temperature range.
High junction temperatures degrade operating lifetimes; operating lifetime
is derated for junction temperatures greater than 125°C. 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.
Note 3:
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
is 40°C/W for the MSOP package.
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.
Note 4:
This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. The maximum
rated junction temperature will be exceeded when this protection is active.
Continuous operation above the specified absolute maximum operating
junction temperature may impair device reliability or permanently damage
the device. The overtemperature protection level is not production tested.
Note 5:
Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
[i=s]This post was last edited by qinyunti on 2022-12-15 13:47[/i]Some netizens are asking why PG2 doesn't light up. Here is an explanation. Because PG2 uses VDDIO2, its VDDIO2 power supply needs to b...
The principle of using common mode inductorsThe inductors with four conductors are different from common inductors.▎Common mode noise suppression Thereare many ways to suppress common mode noise. In a...
Now when I wake up from a nap, I check the company chat room and see that some colleagues have a fever. Before, I couldn’t go out because of the fever, but now I dare not go out because of the fever. ...
I received the MPS POE Ethernet evaluation board for free today. I was a little excited. At first I couldn't find the courier and thought it was a small box, but it turned out to be this big one below...
[i=s]This post was last edited by qwqwqw2088 on 2022-12-15 15:59[/i]The role of DC fast charging (DCFC) in removing barriers to EV adoption is clear. The need for shorter charging times is driving hig...
As the foundation of electronic product design, power supply design is crucial to the development of the electronics industry. With the rapid development of the electronic information industry, power ...
Earlier, there were reports that Huawei will launch a small-screen folding phone with an upside-down flip design equipped with HiSilicon Kirin 9000. The shape may be similar to Samsung Galaxy Z Flip,...[Details]
1. One-way start control circuit
1. Circuit working analysis
1) Close the power switch QS, press the start button SB2, the contactor coil KM is energized, the normally open main con...[Details]
The AVR series of microcontrollers have integrated TWI (Two-wire Serial Interface) bus. This bus has the characteristics of I2C bus, that is, simple wiring, external hardware only needs two pull-up...[Details]
China Energy Storage Network News
: On September 26, 2015, Chinese President Xi Jinping delivered an important speech at the United Nations Development Summit, pointing out that China propose...[Details]
Problem Description:
The microcontroller I have been using before is LPC2109, and I am very familiar with its SPI. Basically, I just used it with
a few minor modifications. For some reason, I need t...[Details]
New flexible consumption model gives businesses access to all Genesys technology Includes low-code tools for orchestrating smooth experiences Beijing, June 30, 2021 - Genesys announced new tools...[Details]
News on the afternoon of October 22, Huawei Developer Conference 2021 (HDC) opened today. Yu Chengdong and other Huawei executives delivered keynote speeches, announcing the HarmonyOS 3 develo...[Details]
Oscilloscopes are like "eyes" to many engineers. Engineers spend more time with oscilloscopes than with their families. Below is a list of possible faults and troubleshooting methods that may occur d...[Details]
It took Momenta 390 days for its assisted driving mileage data to exceed 10 million kilometers; and it took Waymo about ten years to achieve 10 million miles of road test data in 2018. In striking ...[Details]
This will be the best era for autonomous driving, and it will also be the worst era for autonomous driving. Small and exquisite unmanned sales trucks are bumping around "unscrupulously" in closed p...[Details]
This paper proposes a design method for a distributed underwater vehicle controller based on CAN bus, and mainly describes its overall hardware design scheme and implementation method. As a node ...[Details]
Designers can share data between embedded and AI/ML projects, simplifying the creation of edge and endpoint AI applications Beijing, China, September 21, 2023 - Renesas Electronics, a global semico...[Details]
Typical application circuit of TOP414G
Figure TOP414G typical application circuit
The 10W DC/DC converter designed with TOP414G is shown in Figure 1. The DC input voltage range of the convert...[Details]
The PT100 temperature sensor is a temperature measurement device widely used in the industrial field. Its working principle is based on the characteristics of platinum resistance changing with temp...[Details]
stm32/stm8
京公网安备 11010802033920号
EEWORLD
