LT3507A Datasheet PDF - Linear
Part Number | LT3507A | |
Description | Triple Monolithic Step-Down Regulator | |
Manufacturers | Linear | |
Logo | ||
There is a preview and LT3507A download ( pdf file ) link at the bottom of this page. Total 28 Pages |
Preview 1 page No Preview Available ! FEATURES
n Wide Input Range: 4V to 36V
n One 2.7A and Two 1.8A Output Switching
Regulators with Internal Power Switches
n Low Dropout Linear Regulator with External
Transistor
n Antiphase Switching Reduces Ripple
n Independent Run, Tracking/Soft-Start, and Power
Good Indicators Ease Supply Sequencing
n Uses Small Inductors and Ceramic Capacitors
n Adjustable, 250kHz to 2.5MHz Switching Frequency,
Synchronizable Over the Full Range
n User Programmable Overvoltage and Undervoltage
Lockouts
n Thermally Enhanced, 38-Lead TSSOP and
5mm × 7mm QFN Packages
APPLICATIONS
n Automotive
n Industrial Supplies
n Distributed Power Regulation
n DSP Power
LT3507A
Triple Monolithic Step-Down
Regulator with LDO
DESCRIPTION
The LT®3507A is a triple, current mode, DC/DC converter
with internal power switches and a low dropout regulator.
The switching converters are step-down converters capable
of generating one 2.7A output and two 1.8A outputs. All
three converters are synchronized to a single oscillator.
The 2.7A output runs with opposite phase to the other two
converters, reducing input ripple current. Each regulator
has independent shutdown and soft-start circuits, and
generates a power good signal when its output is in regu-
lation, easing power supply sequencing and interfacing
with microcontrollers and DSPs.
The switching frequency is set with a single resistor yielding
a range of 250kHz to 2.5MHz. The high switching frequency
allows the use of small inductors and capacitors resulting
in a very small triple output supply. The constant switching
frequency, combined with low impedance ceramic capaci-
tors, results in low, predictable output ripple. Frequency
foldback and thermal shutdown provide protection against
fault conditions. The LT3507A provides higher output cur-
rent than available with the LT3507.
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.
TYPICAL APPLICATION
5V, 3.3V, 2.5V and 1.8V Step-Down Regulator
VIN
6V TO 36V
VOUT1
1.8V
2.7A
VOUT3
5V
1.8A
22µF
4.7µH
VIN1 VIN2 VIN3
BOOST1
BOOST2
0.22µF
SW1
18.7k
100µF
15k
25.5k
VOUT2
15µH
680pF
FB1
VC1
LT3507A
0.22µF BOOST3
SW3
53.6k
22µF
10.2k
25.5k 680pF
FB3
VC3
SW2
FB2
VC2
BIAS
DRIVE
RT/SYNC
107k GND
FB4
0.22µF
10µH
34.8k
680pF 25.5k 11k
24.3k
11.5k
VOUT2
3.3V
33µF 1.5A
2.2µF
VOUT4
2.5V
0.3A
fSW = 450kHz
3507A TA01a
Start-Up Waveforms—Coincident Tracking
1V/DIV
VOUT3
VOUT2
VOUT4
VOUT1
1ms/DIV
3507 TA01b
3507af
1
|
|
TYPICAL PERFORMANCE CHARACTERISTICS
LT3507A
Efficiency vs Load Current,
Channel 1, VOUT = 1.8V
90 INDUCTOR: NIC NPIM74C4R7MTRF
fSW = 450kHz
80 VIN = 6V
VIN = 12V
70
VIN = 36V
60
50
40
0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7
IOUT (A)
3507A G01
BOOST Pin Current vs Switch
Current, Channels 1, 2 and 3
100
90
80
70
60 CHANNELS 2, 3
50
CHANNEL 1
40
30
20
10
0
0 0.5 1.0 1.5 2.0 2.5 3.0
ISW (A)
3507A G04
Frequency vs Temperature
0.5
0.0
–0.5
–1.0
–1.5
–2.0
–50 –30 –10 30 50 70 90 110 130 150
TEMPERATURE (°C)
3507A G07
Efficiency vs Load Current,
Channels 2 and 3, VOUT = 3.3V
100
90 VIN = 6V
80 VIN = 12V
VIN = 36V
70
60
50
40
0
INDUCTOR: NIC NPIM74C8R2MTRF
fSW = 450kHz
0.3 0.6 0.9 1.2
IOUT (A)
1.5 1.8
3507A G02
VFB vs Temperature
805
804
803
802
801
800
799
798
797
796
795
–50 –30 –10 30 50 70 90 110 130 150
TEMPERATURE (°C)
3507A G05
Frequency vs VFB (Foldback)
1200
1000
RT = 40.2k
TA = 25°C
800
600
400
200
0
0 0.2 0.4 0.6 0.8 1
VFB (V)
3507A G08
CShwaitncnheVlsCE1S,A2T
vs Switch
and 3
Current,
0.6 TA = 25°C
0.5
CHANNELS 2 AND 3
0.4
CHANNEL 1
0.3
0.2
0.1
0
0 0.5 1 1.5 2 2.5 3
ISW (A)
3507A G03
Frequency vs RT
2.5
2.0
1.5
1.0
0.5
0
0 20 40 60 80 100 120 140 160 180 200
RT (kΩ)
3507A G06
ITRK/SS vs Temperature
1.30
1.28
1.26
1.24
1.22
1.20
–50 –30 –10 30 50 70 90 110 130 150
TEMPERATURE (°C)
3507A G09
3507af
5
Preview 5 Page |
Part DetailsOn this page, you can learn information such as the schematic, equivalent, pinout, replacement, circuit, and manual for LT3507A electronic component. |
Information | Total 28 Pages | |
Link URL | [ Copy URL to Clipboard ] | |
Download | [ LT3507A.PDF Datasheet ] |
Share Link :
Electronic Components Distributor
An electronic components distributor is a company that sources, stocks, and sells electronic components to manufacturers, engineers, and hobbyists. |
SparkFun Electronics | Allied Electronics | DigiKey Electronics | Arrow Electronics |
Mouser Electronics | Adafruit | Newark | Chip One Stop |
Featured Datasheets
Part Number | Description | MFRS |
LT3507 | The function is Triple Monolithic Step-Down Regulator. Linear Technology | |
LT3507A | The function is Triple Monolithic Step-Down Regulator. Linear | |
Semiconductors commonly used in industry:
1N4148 |  
BAW56 |
1N5400 |
NE555 | | ||
Quick jump to:
LT35
1N4
2N2
2SA
2SC
74H
BC
HCF
IRF
KA |