900,000+ datasheet pdf search and download

Datasheet4U offers most rated semiconductors data sheet pdf




Analog Devices Semiconductor Electronic Components Datasheet

LTC3859EUHF Datasheet

Buck/Buck/Boost Synchronous Controller

No Preview Available !

FEATURES
n Dual Buck Plus Single Boost Synchronous Controllers
n Outputs Remain in Regulation Through Cold Crank
Down to 2.5V
n Low Operating IQ: 55μA (One Channel On)
n Wide Bias Input Voltage Range: 4.5V to 38V
n Buck Output Voltage Range: 0.8V ≤ VOUT ≤ 24V
n Boost Output Voltage Up to 60V
n RSENSE or DCR Current Sensing
n 100% Duty Cycle for Boost Synchronous MOSFET
n Phase-Lockable Frequency (75kHz to 850kHz)
n Programmable Fixed Frequency (50kHz to 900kHz)
n Selectable Continuous, Pulse-Skipping or Low Ripple
Burst Mode® Operation at Light Loads
n Very Low Buck Dropout Operation: 99% Duty Cycle
n Adjustable Output Voltage Soft-Start or Tracking
n Low Shutdown IQ: 14μA
n Small 38-Pin 5mm × 7mm QFN and TSSOP Packages
APPLICATIONS
n Automotive Always-On and Start-Stop Systems
n Battery Operated Digital Devices
n Distributed DC Power Systems
LTC3859
Low IQ, Triple Output,
Buck/Buck/Boost
Synchronous Controller
DESCRIPTION
The LTC®3859 is a high performance triple output (buck/
buck/boost) synchronous DC/DC switching regulator
controller that drives all N-channel power MOSFET stages.
Constant frequency current mode architecture allows a
phase-lockable switching frequency of up to 850kHz. The
LTC3859 operates from a wide 4.5V to 38V input supply
range. When biased from the output of the boost converter
or another auxiliary supply, the LTC3859 can operate from
an input supply as low as 2.5V after start-up.
The 55μA no-load quiescent current extends operating run-
time in battery powered systems. OPTI-LOOP compensation
allows the transient response to be optimized over a wide
range of output capacitance and ESR values. The LTC3859
features a precision 0.8V reference for the bucks, 1.2V
reference for the boost and a power good output indicator.
Independent TRACK/SS pins for each controller ramp the out-
put voltages during start-up. Current foldback limits MOSFET
heat dissipation during short-circuit conditions. The PLLIN/
MODE pin selects among Burst Mode operation, pulse-skipping
mode, or continuous inductor current mode at light loads.
All registered trademarks and trademarks are the property of their respective owners. Protected
by U.S. Patents including 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION
VOUT3
REGULATED AT 10V WHEN VIN < 10V
FOLLOWS VIN WHEN VIN > 10V
220µF
1µF
499k
VFB3
VBIAS
68.1k
TG1
VIN
2.5V TO 38V
(START-UP ABOVE 5V)
2mΩ 1.2µH
220µF
4.7µF
SW1, 2, 3
TG3
SW1
SW3 LTC3859
BG1
BG3
SENSE3
SENSE3+
INTVCC
BOOST1, 2, 3
0.1µF
ITH1, 2, 3
SENSE1+
SENSE1
VFB1
RUN1, 2, 3
EXTVCC
TG2
SW2
BG2
0.1µF
SENSE2+
TRACK/SS1, 2
SENSE2–
SS3
VFB2
PGND SGND
3859 TA01
4.9µH 6mΩ
VOUT1
5V
5A
68.1k 357k
220µF
6.5µH 8mΩ
VOUT2
8.5V
3A
68.1k 649k
68µF
Document Feedback
For more information www.analog.com
Efficiency vs Input Voltage
100
95
VOUT2 = 8.5V
90
VOUT1 = 5V
85
80
75
70
65
60
55 FIGURE 12 CIRCUIT
50 ILOAD = 2A
0 5 10 15 20 25 30
INPUT VOLTAGE (V)
35 40
3859 TA01b
Rev. C
1


Analog Devices Semiconductor Electronic Components Datasheet

LTC3859EUHF Datasheet

Buck/Buck/Boost Synchronous Controller

No Preview Available !

LTC3859
ABSOLUTE MAXIMUM RATINGS (Notes 1, 3)
Bias Input Supply Voltage (VBIAS)............... –0.3V to 40V
Buck Top Side Driver Voltages
(BOOST1, BOOST2) .............................. –0.3V to 46V
Boost Top Side Driver Voltages
(BOOST3) ............................................. –0.3V to 76V
Buck Switch Voltage (SW1, SW2) ................. –5V to 40V
Boost Switch Voltage (SW3) ......................... –5V to 70V
INTVCC, (BOOST1–SW1),
(BOOST2–SW2), (BOOST3–SW3),........... –0.3V to 6V
RUN1, RUN2, RUN3 ..................................... –0.3V to 8V
Maximum Current Sourced Into Pin
from Source >8V...............................................100µA
SENSE1+, SENSE2+, SENSE1
SENSE2Voltages...................................... –0.3V to 28V
SENSE3+, SENSE3Voltages...................... –0.3V to 40V
FREQ Voltages.......................................–0.3V to INTVCC
EXTVCC....................................................... –0.3V to 14V
ITH1, ITH2, ITH3, VFB1, VFB2, VFB3 Voltages..... –0.3V to 6V
PLLIN/MODE, PGOOD1, OV3 Voltages ......... –0.3V to 6V
TRACK/SS1, TRACK/SS2, SS3 Voltages ...... –0.3V to 6V
Operating Junction Temperature Range
(Note 2).............................................. –40°C to 125°C
Storage Temperature Range................... –65°C to 150°C
PIN CONFIGURATION
TOP VIEW
ITH1 1
VFB1 2
SENSE1+ 3
SENSE14
FREQ 5
PLLIN/MODE 6
SS3 7
SENSE3+ 8
SENSE39
VFB3 10
ITH3 11
SGND 12
RUN1 13
RUN2 14
RUN3 15
SENSE216
SENSE2+ 17
VFB2 18
ITH2 19
39
PGND
38 TRACK/SS1
37 PGOOD1
36 TG1
35 SW1
34 BOOST1
33 BG1
32 SW3
31 TG3
30 BOOST3
29 BG3
28 VBIAS
27 EXTVCC
26 INTVCC
25 BG2
24 BOOST2
23 SW2
22 TG2
21 OV3
20 TRACK/SS2
FE PACKAGE
38-LEAD PLASTIC TSSOP
TJMAX = 125°C, qJA = 25°C/W
EXPOSED PAD (PIN 39) IS PGND, MUST BE SOLDERED TO PCB
TOP VIEW
FREQ 1
PLLIN/MODE 2
SS3 3
SENSE3+ 4
SENSE35
VFB3 6
ITH3 7
SGND 8
RUN1 9
RUN2 10
RUN3 11
SENSE212
38 37 36 35 34 33 32
39
PGND
13 14 15 16 17 18 19
31 SW1
30 BOOST1
29 BG1
28 SW3
27 TG3
26 BOOST3
25 BG3
24 VBIAS
23 EXTVCC
22 INTVCC
21 BG2
20 BOOST2
UHF PACKAGE
38-LEAD (5mm × 7mm) PLASTIC QFN
TJMAX = 125°C, qJA = 34°C/W
EXPOSED PAD (PIN 39) IS PGND, MUST BE SOLDERED TO PCB
Rev. C
2
For more information www.analog.com


Part Number LTC3859EUHF
Description Buck/Buck/Boost Synchronous Controller
Maker Analog Devices
PDF Download

LTC3859EUHF Datasheet PDF






Similar Datasheet

1 LTC3859EUHF Buck/Buck/Boost Synchronous Controller
Analog Devices





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