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

LTC3788IUH#PBF

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P32
LTC3788
1
3788fc
15nF
4.7µF
2.7k
12.1k
12.1k
V
OUT
12V AT 5A
V
OUT
24V AT 3A
V
IN
4.5V TO 12V START-UP VOLTAGE
OPERATES THROUGH TRANSIENTS DOWN TO 2.5V
V
IN
0.1µF
100pF
0.1µF
220µF
220µF
TG1
BOOST1
SW1
BG1
FREQ
SS1 SGND SS2
SENSE1
+
SENSE1
–
VFB1
ITH1
VBIAS
LTC3788
INTV
CC
PLLIN/MODE
TG2
BOOST2
SW2
BG2
SENSE2
+
SENSE2
–
VFB2
ITH2
PGND
0.1µF
15nF
8.66k
220pF
232k
0.1µF
4.7µF
110k
3788 TA01a
220µF
3.3µH
1.25µH
3mΩ 4mΩ
Typical applicaTion
DescripTion
2-Phase, Dual Output
Synchronous Boost Controller
The LT C
®
3788 is a high performance 2-phase dual
synchronous boost converter controller that drives all
N-channel power MOSFETs. Synchronous rectification
increases efficiency, reduces power losses and eases
thermal requirements, allowing the LTC3788 to be used
in high power boost applications.
A constant-frequency current mode architecture allows a
phase-lockable frequency of up to 850kHz. OPTI-LOOP
®
compensation allows the transient response to be optimized
over a wide range of output capacitance and ESR values.
The LTC3788 features a precision 1.2V reference and dual
power good output indicators. A 4.5V to 38V input supply
range encompasses a wide range of system architectures
and battery chemistries.
Independent SS pins for each controller ramp the output
voltages during start-up. The PLLIN/MODE pin selects
among Burst Mode
®
operation, pulse-skipping mode or
continuous inductor current mode at light loads.
For a leaded 28-lead SSOP package with a fixed current
limit and one PGOOD output, without phase modulation
or a clock output, see the LTC3788-1 data sheet.
L, LT , LT C , LT M , Linear Technology, Burst Mode, OPTI-LOOP, PolyPhase and the Linear logo
are registered trademarks and No R
SENSE
and ThinSOT are 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, 6144194, 6177787, 6580258.
FeaTures
applicaTions
n
Synchronous Operation for Highest Efficiency and
Reduced Heat Dissipation
n
Wide Input Range: 4.5V to 38V (40V Abs Max) and
Operates Down to 2.5V After Start-Up
n
Output Voltages Up to 60V
n
±1% 1.2V Reference Voltage
n
R
SENSE
or Inductor DCR Current Sensing
n
100% Duty Cycle Capability for Synchronous MOSFET
n
Low Quiescent Current: 125µA
n
Phase-Lockable Frequency (75kHz to 850kHz)
n
Programmable Fixed Frequency (50kHz to 900kHz)
n
Selectable Current Limit
n
Adjustable Output Voltage Soft-Start
n
Power Good Output Voltage Monitors
n
Low Shutdown Current I
Q
: <8μA
n
Internal LDO Powers Gate Drive from VBIAS or EXTV
CC
n
Thermally Enhanced Low Profile 32-Pin 5mm × 5mm
QFN Package
n
Industrial
n
Automotive
n
Medical
n
Military
Efficiency and Power Loss
vs Output Current
OUTPUT CURRENT (A)
40
EFFICIENCY (%)
POWER LOSS (mW)
50
60
70
80
3788 TA01b
30
20
10
0
90
100
10
100
1000
1
0.1
10000
0.01 0.1 1 10
V
IN
= 12V
V
OUT
= 24V
Burst Mode OPERATION
FIGURE 9 CIRCUIT
0.0001 0.0010.00001
LTC3788
2
3788fc
pin conFiguraTion
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C, VBIAS = 12V, unless otherwise noted (Note 2).
absoluTe MaxiMuM raTings
VBIAS ........................................................ –0.3V to 40V
BOOST1, BOOST2 ...................................... –0.3V to 76V
SW1, SW2 .................................................. –0.3V to 70V
RUN1, RUN2 ................................................ –0.3V to 8V
Maximum Current Sourced into Pin
from Source > 8V .............................................100µA
PGOOD1, PGOOD2, PLLIN/MODE ............... –0.3V to 6V
INTV
CC
, (BOOST1-SW1, BOOST2-SW2) ...... –0.3V to 6V
EXTV
CC
........................................................ –0.3V to 6V
SENSE1
+
, SENSE1
–
,
SENSE2
+
, SENSE2
–
.................................... –0.3V to 40V
SENSE1
+
– SENSE1
–
,
SENSE2
+
– SENSE2
–
................................. –0.3V to 0.3V
I
LIM
, SS1, SS2, ITH1, ITH2, FREQ,
PHASMD, VFB1, VFB2 ...........................–0.3V to INTV
CC
Operating Junction Temperature Range ....–40°C to 125°C
Storage Temperature Range .................. –65°C to 125°C
(Notes 1, 3)
32
33
GND
31 30 29 28 27 26 25
9 10 11 12
TOP VIEW
UH PACKAGE
32-LEAD (5mm × 5mm) PLASTIC QFN
13 14 15 16
17
18
19
20
21
22
23
24
8
7
6
5
4
3
2
1SENSE1
–
FREQ
PHASMD
CLKOUT
PLLIN/MODE
SGND
RUN1
RUN2
BOOST1
BG1
VBIAS
PGND
EXTV
CC
INTV
CC
BG2
BOOST2
SENSE1
+
VFB1
ITH1
SS1
ILIM
PGOOD1
SW1
TG1
SENSE2
–
SENSE2
+
VFB2
ITH2
SS2
PGOOD2
SW2
TG2
T
JMAX
= 125°C, θ
JA
= 34°C/W
EXPOSED PAD (PIN 33) IS GND, MUST BE SOLDERED TO PCB
orDer inForMaTion
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3788EUH#PBF LTC3788EUH#TRPBF 3788
32-Lead (5mm × 5mm) Plastic QFN
–40°C to 125°C
LTC3788IUH#PBF LTC3788IUH#TRPBF 3788
32-Lead (5mm × 5mm) Plastic QFN
–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 LT C 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/
elecTrical characTerisTics
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
VBIAS Chip Bias Voltage Operating Range 4.5 38 V
V
FB1,2
Regulated Feedback Voltage I
TH
= 1.2V (Note 4)
l
1.188 1.200 1.212 V
I
FB1,2
Feedback Current (Note 4) ±5 ±50 nA
V
REFLNREG
Reference Line Voltage Regulation VBIAS = 6V to 38V 0.002 0.02 %/V
LTC3788
3
3788fc
elecTrical characTerisTics
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C, VBIAS = 12V, unless otherwise noted (Note 2).
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
LOADREG
Output Voltage Load Regulation (Note 4)
Measured in Servo Loop;
∆I
TH
Voltage = 1.2V to 0.7V
l
0.01 0.1 %
Measured in Servo Loop;
∆I
TH
Voltage = 1.2V to 2V
l
–0.01 –0.1 %
g
m1,2
Error Amplifier Transconductance I
TH
= 1.2V 2 mmho
I
Q
Input DC Supply Current (Note 5)
Pulse-Skipping or Forced Continuous Mode
(One Channel On)
RUN1 = 5V and RUN2 = 0V or RUN1 = 0V
and RUN2 = 5V; V
FB1(2)
= 1.25V (No Load)
0.9 mA
Pulse-Skipping or Forced Continuous Mode
(Both Channels On)
RUN1,2 = 5V; V
FB1,2
= 1.25V (No Load) 1.2 mA
Sleep Mode
(One Channel On)
RUN1 = 5V and RUN2 = 0V or RUN1 = 0V
and RUN2 = 5V; V
FB1(2)
= 1.25V (No Load)
125 190 µA
Sleep Mode
(Both Channels On)
RUN1,2 = 5V; V
FB1,2
= 1.25V (No Load) 200 300 µA
Shutdown RUN1,2 = 0V 8 20 µA
UVLO INTV
CC
Undervoltage Lockout Thresholds V
INTVCC
Ramping Up
l
4.1 4.3 V
V
INTVCC
Ramping Down
l
3.6 3.8 V
V
RUN1,2
RUN Pin On Threshold V
RUN
Rising
l
1.18 1.28 1.38 V
V
RUNHYS
RUN Pin Hysteresis 100 mV
I
RUN1,2
RUN Pin Hysteresis Current V
RUN
> 1.28V 4.5 µA
I
RUN1,2
RUN Pin Current V
RUN
< 1.28V 0.5 µA
I
SS1,2
Soft-Start Charge Current V
SS
= GND 7 10 13 µA
V
SENSE(MAX)
Maximum Current Sense Threshold V
FB
= 1.1V, I
LIM
= INTV
CC
l
90 100 110 mV
V
FB
= 1.1V, I
LIM
= Float
l
68 75 82 mV
V
FB
= 1.1V, I
LIM
= GND
l
42 50 56 mV
V
SENSE(CM)
SENSE Pins Common Mode Range (BOOST
Converter Input Supply Voltage V
IN
)
2.5 38 V
I
SENSE1,2
+
SENSE
+
Pin Current V
FB
= 1.1V, I
LIM
= Float 200 300 µA
I
SENSE1,2
–
SENSE
–
Pin Current V
FB
= 1.1V, I
LIM
= Float ±1 µA
t
r(TG1,2)
Top Gate Rise Time C
LOAD
= 3300pF (Note 6) 20 ns
t
f(TG1,2)
Top Gate Fall Time C
LOAD
= 3300pF (Note 6) 20 ns
t
r(BG1,2)
Bottom Gate Rise Time C
LOAD
= 3300pF (Note 6) 20 ns
t
f(BG1,2)
Bottom Gate Fall Time C
LOAD
= 3300pF (Note 6) 20 ns
R
UP(TG1,2)
Top Gate Pull-Up Resistance 1.2 Ω
R
DN(TG1,2)
Top Gate Pull-Down Resistance 1.2 Ω
R
UP(TG1,2)
Bottom Gate Pull-Up Resistance 1.2 Ω
R
DN(TG1,2)
Bottom Gate Pull-Down Resistance 1.2 Ω
t
D(TG/BG)
Top Gate Off to Bottom Gate On
Switch-On Delay Time
C
LOAD
= 3300pF (Each Driver) 70 ns
t
D(BG/TG)
Bottom Gate Off to Top Gate On
Switch-On Delay Time
C
LOAD
= 3300pF (Each Driver) 70 ns
DF
MAX(BG1,2)
Maximum BG Duty Factor 96 %
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P21P22-P24P25-P27P28-P30P31-P32

LTC3788IUH#PBF

Mfr. #:
Buy LTC3788IUH#PBF
Manufacturer:
Analog Devices / Linear Technology
Description:
Switching Voltage Regulators 2-Phase, 2x Out Sync Boost Cntr
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet