900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf




Linear Technology Electronic Components Datasheet

LTC3851 Datasheet

Synchronous Step-Down Switching Regulator Controller

No Preview Available !

FEATURESwww.datasheet4u.com
n Wide VIN Range: 4V to 38V Operation
n RSENSE or DCR Current Sensing
n ±1% Output Voltage Accuracy
n Phase-Lockable Fixed Frequency: 250kHz to 750kHz
n Dual N-Channel MOSFET Synchronous Drive
n Very Low Dropout Operation: 99% Duty Cycle
n Adjustable Output Voltage Soft-Start or Tracking
n Output Current Foldback Limiting
n Output Overvoltage Protection
n 5V Internal Regulator
n OPTI-LOOP® Compensation Minimizes COUT
n Selectable Continuous, Pulse-Skipping or
Burst Mode® Operation at Light Loads
n Low Shutdown IQ: 20μA
n VOUT Range: 0.8V to 5.5V
n 16-Lead Narrow SSOP or 3mm × 3mm QFN Package
APPLICATIONS
n Automotive Systems
n Telecom Systems
n Industrial Equipment
n Distributed DC Power Systems
LTC3851
Synchronous
Step-Down Switching
Regulator Controller
DESCRIPTION
The LTC®3851 is a high performance synchronous
step-down switching regulator controller that drives
an all N-channel synchronous power MOSFET stage. A
constant frequency current mode architecture allows a
phase-lockable frequency of up to 750kHz.
OPTI-LOOP compensation allows the transient response
to be optimized over a wide range of output capacitance
and ESR values. The LTC3851 features a precision 0.8V
reference that is compatible with a wide 4V to 38V input
supply range.
The TK/SS pin ramps the output voltage during start-up.
Current foldback limits MOSFET heat dissipation during
short-circuit conditions. The MODE/PLLIN pin selects
among Burst Mode operation, pulse skipping mode or
continuous inductor current mode at light loads and allows
the IC to be synchronized to an external clock.
, LT, LTC, LTM, Burst Mode and OPTI-LOOP are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 5408150, 5481178, 5705919, 5929620, 6304066,
6498466, 6580258, 6611131.
TYPICAL APPLICATION
High Efficiency Synchronous Step-Down Converter
10nF
1k
ILIM VIN
FREQ/PLLFLTR TG
0.1μF
RUN SW
LTC3851
TK/SS BOOST
INTVCC
ITH
100pF
BG
GND
SENSE+
PLLIN/MODE
SENSE
VFB
0.22μF
0.68μH
10k
150μF
VIN
4V TO 38V
VOUT
3.3V
10A
330μF
0.22μF 13k
62.5k
20k
3851 TA01a
Efficiency and Power Loss
vs Load Current
100
VIN = 12V
95 VOUT = 3.3V
90
85
80
EFFICIENCY
10000
1000
75
POWER LOSS
70
65 100
60
55
50
10
100 1000
LOAD CURRENT (mA)
10
10000
3851TA01b
3851f
1


Linear Technology Electronic Components Datasheet

LTC3851 Datasheet

Synchronous Step-Down Switching Regulator Controller

No Preview Available !

LTC3851
ABSOLUTE MAXIMUM RATINGS (Note 1)
Input Supply Voltage (VIN) ......................... 40V to –0.3V
Topside Driver Voltage (BOOST) ................ 46V to –0.3V
wwwS.dwatiatschheeVt4oult.caogme (SW) ..................................... 40V to –5V
INTVCC, (BOOST – SW), RUN ...................... 6V to –0.3V
TK/SS, ILIM............................................ INTVCC to –0.3V
SENSE+, SENSE.......................................... 6V to –0.3V
MODE/PLLIN, FREQ/PLLFLTR............... INTVCC to –0.3V
ITH, VFB Voltages .......................................... 3V to –0.3V
INTVCC Peak Output Current ..................................50mA
Operating Temperature Range (Note 2).... –40°C to 85°C
Junction Temperature (Note 3) ............................. 125°C
Storage Temperature Range
GN ..................................................... –65°C to 150°C
UD ......................................................... –65 to 125°C
Lead Temperature (Soldering, 10 sec)
GN .................................................................... 300°C
PIN CONFIGURATION
TOP VIEW
MODE/PLLIN 1
FREQ/PLLFLTR 2
RUN 3
TK/SS 4
ITH
FB
SENSE
SENSE+
5
6
7
8
16 SW
15 TG
14 BOOST
13 VIN
12 INTVCC
11 BG
10 GND
9 ILIM
GN PACKAGE
16-LEAD PLASTIC SSOP NARROW
TJMAX = 125°C, θJA = 90°C/W
TOP VIEW
16 15 14 13
RUN 1
12 BOOST
TK/SS 2 17 11 VIN
ITH 3
10 INTVCC
FB 4
9 BG
5678
UD PACKAGE
16-LEAD (3mm s 3mm) PLASTIC QFN
TJMAX = 125°C, θJA = 68°C/W, θJC = 4.2°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
LTC3851EGN#PBF
LTC3851EGN#TRPBF
3851
16-Lead Plastic SSOP
LTC3851EUD#PBF
LTC3851EUD#TRPBF
LCXN
16-Lead (3mm × 3mm) Plastic QFN
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/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
3851f
2


Part Number LTC3851
Description Synchronous Step-Down Switching Regulator Controller
Maker Linear Technology
PDF Download

LTC3851 Datasheet PDF






Similar Datasheet

1 LTC3850 2-Phase Synchronous Step-Down Switching Controller
Linear Technology
2 LTC3850-1 2-Phase Synchronous Step-Down Switching Controller
Linear Technology
3 LTC3850-2 2-Phase Synchronous Step-Down Switching Controller
Linear Technology
4 LTC3851 Synchronous Step-Down Switching Regulator Controller
Linear Technology
5 LTC3851-1 Synchronous Step-Down Switching Regulator Controller
Linear Technology
6 LTC3851A Synchronous Step-Down Switching Regulator Controller
Linear Technology
7 LTC3851A-1 Synchronous Step-Down Switching Regulator Controller
Linear Technology
8 LTC3852 Synchronous Step-Down DC/DC Controller
Linear
9 LTC3853 Multiphase Synchronous Step-Down Controller
Linear Technology





Part Number Start With

0    1    2    3    4    5    6    7    8    9    A    B    C    D    E    F    G    H    I    J    K    L    M    N    O    P    Q    R    S    T    U    V    W    X    Y    Z



Site map

Webmaste! click here

Contact us

Buy Components

Privacy Policy