OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

LT3581EMSE#TRPBF

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P33P34-P36
LT3581
1
3581fb
For more information www.linear.com/LT3581
TYPICAL APPLICATION
DESCRIPTION
3.3A Boost/Inverting DC/DC
Converter with Fault Protection
The LT
®
3581 is a PWM DC/DC converter with built-in fault
protection features to aid in protecting against output
shorts, input/output overvoltages, and overtemperature
conditions. The part consists of a 42V master switch, and
a 42V slave switch that can be tied together for a total
current limit of 3.3A.
The LT3581 is ideal for many local power supply designs. It
can be easily configured in Boost, SEPIC, Inverting or Flyback
configurations, and is capable of generating 12V at 830mA,
or –12V at 625mA from a 5V input. In addition, the LT3581’s
slave switch allows the part to be configured in high voltage,
high power charge pump topologies that are very efficient
and require fewer components than traditional circuits.
The LT3581’s switching frequency range can be set bet ween
200kHz and 2.5MHz. The part may be clocked internally at
a frequency set by the resistor from the RT pin to ground,
or it may be synchronized to an external clock. A buffered
version of the clock signal is driven out of the CLKOUT
pin, and may be used to synchronize other compatible
switching regulator ICs to the LT3581.
The LT3581 also features innovative SHDN pin circuitry that
allows for slowly varying input signals and an adjustable
undervoltage lockout function. Additional features such
as frequency foldback and soft-start are integrated. The
LT3581 is available in 14-Pin 4mm × 3mm DFN and 16-
Lead MSE packages.
Output Short Protected, 5V to 12V Boost Converter Operating at 2MHz
FEATURES
APPLICATIONS
n
3.3A, 42V Combined Power Switch
n
Master/Slave (1.9A/1.4A) Switch Design
n
Output Short Circuit Protection
n
Wide Input Range: 2.5V to 22V Operating,
40V Maximum Transient
n
Switching Frequency Up to 2.5MHz
n
Easily Configurable as a Boost, SEPIC, Inverting or
Flyback Converter
n
User Configurable Undervoltage Lockout
n
Low V
CESAT
Switch: 250mV at 2.75A (Typical)
n
Can be Synchronized to External Clock
n
Can Be Synchronized to other Switching Regulators
n
High Gain SHDN Pin Accepts Slowly Varying Input
Signals
n
14-Pin 4mm × 3mm DFN and 16-Lead MSE Packages
n
Local Power Supply
n
Vacuum Fluorescent Display (VFD) Bias Supplies
n
TFT-LCD Bias Supplies
n
Automotive Engine Control Unit (ECU) Power
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 7579816.
V
IN
5V
V
IN
6.04k
100k
130k
43.2k
4.7µF
1.5µH
1nF
3581 TA01
0.1µF
4.7µF
10.5k
4.7µF
V
OUT
12V
830mA
SW1 SW2
FB
CLKOUT
GATE
V
C
SS
V
IN
RT
GND
SYNC
FAULT
SHDN
LT3581
56pF
18.7k
10k
LOAD CURRENT (mA)
0
50
EFFICIENCY (%)
POWER LOSS (mW)
55
65
70
75
400
100
95
3581 TA01b
60
200 1000800600
80
85
90
0
200
600
2000
1200
1400
1600
1800
400
800
1000
Efficiency and Power Loss vs
Load Current
LT3581
2
3581fb
For more information www.linear.com/LT3581
PIN CONFIGURATION
ABSOLUTE MAXIMUM RATINGS
V
IN
Voltage ................................................. –0.3V to 40V
SW1/SW2 Voltage ..................................... –0.4V to 42V
RT Voltage ................................................... –0.3V to 5V
SS, FB Voltage .......................................... –0.3V to 2.5V
V
C
Voltage .................................................... –0.3V to 2V
SHDN Voltage ............................................ –0.3V to 40V
SYNC Voltage ............................................ –0.3V to 5.5V
GATE Voltage ............................................. –0.3V to 80V
FA ULT Voltage ............................................ –0.3V to 40V
(Note 1)
1
2
3
4
5
6
7
14
13
12
11
10
9
8
SYNC
SS
RT
SHDN
CLKOUT
SW2
SW2
FB
V
C
GATE
FAULT
V
IN
SW1
SW1
TOP VIEW
DE14 PACKAGE
14-PIN (4mm × 3mm) PLASTIC DFN
15
GND
T
JMAX
= 125°C, θ
JA
= 43°C/W, θ
JC
= 4.3°C/W
EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB
1
2
3
4
5
6
7
8
FB
V
C
GATE
FAULT
V
IN
SW1
SW1
SW1
16
15
14
13
12
11
10
9
SYNC
SS
RT
SHDN
CLKOUT
SW2
SW2
SW2
TOP VIEW
MSE PACKAGE
16-LEAD PLASTIC MSOP
17
GND
T
JMAX
= 125°C, θ
JA
= 45°C/W, θ
JC
= 10°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LT3581EDE#PBF LT3581EDE#TRPBF 3581
14-Lead (4mm × 3mm) Plastic DFN
–40°C to 125°C
LT3581IDE#PBF LT3581IDE#TRPBF 3581
14-Lead (4mm × 3mm) Plastic DFN
–40°C to 125°C
LT3581HDE#PBF LT3581HDE#TRPBF 3581
14-Lead (4mm × 3mm) Plastic DFN
–40°C to 150°C
LT3581EMSE#PBF LT3581EMSE#TRPBF 3581 16-Lead Plastic MSOP –40°C to 125°C
LT3581IMSE#PBF LT3581IMSE#TRPBF 3581 16-Lead Plastic MSOP –40°C to 125°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/
FA ULT Current .....................................................±500µA
CLKOUT Voltage .......................................... –0.3V to 3V
CLKOUT Current.......................................................1mA
Operating Junction Temperature Range
LT3581E (Notes 2, 4)
......................... –40°C to 125°C
LT3581I (Notes 2, 4)
.......................... –40°C to 125°C
LT3581H (Notes 2, 4) .........................–40°C to 150°C
Storage Temperature Range ..................–65°C to 150°C
LT3581
3
3581fb
For more information www.linear.com/LT3581
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS
Minimum Input Voltage
l
2.3 2.5 V
V
IN
Overvoltage Lockout 22.1 23.5 25 V
Positive Feedback Voltage
l
1.195 1.215 1.230 V
Negative Feedback Voltage
l
3 9 16 mV
Positive FB Pin Bias Current V
FB
= Positive Feedback Voltage, Current into Pin
l
81 83.3 85 µA
Negative FB Pin Bias Current V
FB
= Negative Feedback Voltage, Current out of Pin
l
81 83.3 85.5 µA
Error Amp Transconductance ΔI = 10μA 270 µmhos
Error Amp Voltage Gain 70 V/V
Quiescent Current Not Switching 1.9 2.3 mA
Quiescent Current in Shutdown V
SHDN
= 0V 0 1 µA
Reference Line Regulation 2.5V ≤ V
IN
≤ 20V 0.01 0.05 %/V
Switching Frequency, f
OSC
R
T
= 34k
l
2.25 2.5 2.75 MHz
R
T
= 432k
l
180 200 220 kHz
Switching Frequency in Foldback Compared to Normal f
OSC
1/6 ratio
Switching Frequency Range Free-Running or Synchronizing
l
200 2500 kHz
SYNC High Level for Synchronization
l
1.3 V
SYNC Low Level for Synchronization
l
0.4 V
SYNC Clock Pulse Duty Cycle V
SYNC
= 0V to 2V 20 80 %
Recommended Minimum SYNC Ratio
f
SYNC
/f
OSC
3/4
Minimum Off-Time 45 ns
Minimum On-Time 55 ns
SW1 Current Limit At All Duty Cycles
l
1.9 2.4 3 A
Current Sharing (SW2/SW1) 78 %
SW1 + SW2 Current Limit At All Duty Cycles, SW2/SW1 = 78% (Note 3)
l
3.3 4.3 5.4 A
Switch V
CESAT
SW1 & SW2 Tied Together, I
SW1
+ I
SW2
= 2.75A 250 mV
SW1 Leakage Current V
SW1
= 5V 0.01 1 µA
SW2 Leakage Current V
SW2
= 5V 0.01 1 µA
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 5V, V
SHDN
= V
IN
, V
FAULT
= V
IN
, unless otherwise noted. (Note 2).
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P33P34-P36

LT3581EMSE#TRPBF

Mfr. #:
Buy LT3581EMSE#TRPBF
Manufacturer:
Analog Devices / Linear Technology
Description:
Switching Voltage Regulators 3A Boost/Inverting DC/DC Converter with Fault Protection
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet