FeaTures
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LT8330
Low I
Q
Boost/SEPIC/
Inverting Converter
with 1A, 60V Switch
DescripTion
The
LT
®
8330
is a current mode DC/DC converter capable
of generating either positive or negative output voltages
using a single feedback pin. It can be configured as a
boost, SEPIC or inverting converter consuming as low as
6µA of quiescent current. Low ripple Burst Mode opera-
tion maintains high efficiency down to very low output
currents while keeping the output ripple below 15mV in
a typical application. The internally compensated current
mode architecture results in stable operation over a wide
range of input and output voltages. Integrated soft-start
and frequency foldback functions are included to control
inductor current during start-up. The 2MHz operation
combined with small package options, enables low cost,
area efficient solutions.
L,
LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
n
n
n
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3V to 40V Input Voltage Range
Ultralow Quiescent Current and Low Ripple Burst
Mode
®
Operation: I
Q
= 6µA
1A, 60V Power Switch
Positive or Negative Output Voltage Programming
with a Single Feedback Pin
Fixed 2MHz Switching Frequency
Accurate 1.6V EN/UVLO Pin Threshold
Internal Compensation and Soft-Start
Low Profile (1mm) ThinSOT™ Package
Low Profile (0.75mm) 8-Lead (3mm × 2mm) DFN
Package
applicaTions
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Industrial and Automotive
Telecom
Medical Diagnostic Equipment
Portable Electronics
Typical applicaTion
48V Boost Converter
V
IN
12V
6.8µH
4.7µF
V
IN
LT8330
EN/UVLO
INTV
CC
1µF
FBX
GND
1M
4.7pF
SW
EFFICIENCY (%)
4.7µF
V
OUT
48V
135mA
100
90
80
70
60
50
40
30
20
10
0
0
EFFICIENCY
POWER LOSS
40
80
120
LOAD CURRENT (mA)
Efficiency and Power Loss
1000
900
800
700
600
500
400
300
200
100
0
160
8330 TA01b
POWER LOSS (mW)
34.8k
For more information
www.linear.com/LT8330
1
8330f
LT8330
absoluTe MaxiMuM raTings
(Note 1)
SW ............................................................................60V
V
IN
, EN/UVLO............................................................40V
EN/UVLO Pin Above V
IN
Pin........................................6V
INTV
CC
(Note 2) ..........................................................4V
FBX ...........................................................................±4V
Operating Junction Temperature (Note 3)
LT8330E, LT8330I ............................. –40°C to 125°C
LT8330H ............................................ –40°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
pin conFiguraTion
TOP VIEW
FBX 1
NC 2
SW 3
SW 4
9
8
7
6
5
EN/UVLO
INTV
CC
V
IN
GND
SW 1
GND 2
FBX 3
TOP VIEW
6 V
IN
5 INTV
CC
4 EN/UVLO
DDB PACKAGE
8-LEAD (3mm
×
2mm) PLASTIC DFN
θ
JA
= 60°C/W
EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB
S6 PACKAGE
6-LEAD PLASTIC TSOT-23
θ
JA
= 125°C/W,
θ
JC
= 102°C/W
orDer inForMaTion
LEAD FREE FINISH
LT8330ES6#PBF
LT8330IS6#PBF
LT8330HS6#PBF
LT8330EDDB#PBF
LT8330IDDB#PBF
LT8330HDDB#PBF
TAPE AND REEL
LT8330ES6#TRPBF
LT8330IS6#TRPBF
LT8330HS6#TRPBF
LT8330EDDB#TRPBF
LT8330IDDB#TRPBF
LT8330HDDB#TRPBF
PART MARKING
LTGMQ
LTGMQ
LTGMQ
LGRC
LGRC
LGRC
PACKAGE DESCRIPTION
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
6-Lead Plastic TSOT-23
8-Lead (3mm × 2mm) Plastic DFN
8-Lead (3mm × 2mm) Plastic DFN
8-Lead (3mm × 2mm) Plastic DFN
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Consult LTC Marketing for information on nonstandard 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/
2
8330f
For more information
www.linear.com/LT8330
LT8330
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V, EN/UVLO = 12V unless otherwise noted.
PARAMETER
V
IN
Operating Voltage Range
V
IN
Quiescent Current at Shutdown
V
EN/UVLO
= 0.2V
l
elecTrical characTerisTics
CONDITIONS
MIN
l
TYP
0.9
2
2
3.6
5.5
8.5
780
840
MAX
40
2
5
5
9.5
10
15
1100
1200
1.632
–0.780
0.015
0.015
10
UNITS
V
µA
µA
µA
µA
µA
µA
µA
µA
V
V
%/V
%/V
nA
MHz
ns
ns
A
mΩ
µA
V
V
nA
ms
3
V
EN/UVLO
= 1.5V
l
V
IN
Quiescent Current
V
EN/UVLO
= 2V, (Sleep Mode) (Not Switching)
l
V
EN/UVLO
= 2V, (Active Mode) (Not Switching)
l
FBX Regulation
FBX Regulation Voltage
FBX Line Regulation
FBX Pin Current
Oscillator
Switching Frequency (f
OSC
)
Minimum On-Time
Minimum Off-Time
Switch
Maximum Switch Current Limit Threshold
Switch R
DS(ON)
Switch Leakage Current
EN/UVLO Logic
EN/UVLO Pin Threshold (Rising)
EN/UVLO Pin Threshold (Falling)
EN/UVLO Pin Current
Soft-Start
Soft-Start Time
V
IN
= 24V
1
Start Switching
Stop Switching
V
EN/UVLO
= 1.6V
l
l
l
l
FBX > 0V
FBX < 0V
FBX > 0V, 3V < V
IN
< 40V
FBX < 0V, 3V < V
IN
< 40V
FBX = 1.6V, –0.8V
V
IN
= 24V
V
IN
= 24V
V
IN
= 24V
l
l
1.568
–0.820
1.6
–0.80
0.005
0.005
l
–10
1.85
2.0
65
47
1.0
1.2
330
0.1
1.620
1.556
–40
1.68
1.60
l
2.15
105
65
1.4
1
1.745
1.644
40
I
SW
= 0.5A
V
SW
= 60V
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
INTV
CC
cannot be externally driven. No additional components or
loading is allowed on this pin.
Note 3:
The LT8330E is guaranteed to meet performance specifications
from 0°C to 125°C junction temperature. Specifications over the –40°C
to 125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LT8330I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The LT8330H is guaranteed over the full –40°C to
150°C operating junction temperature range. High junction temperatures
degrade operating lifetimes. Operating lifetime is derated at junction
temperatures greater than 125°C.
Note 4:
The IC includes overtemperature protection that is intended to
protect the device during overload conditions. Junction temperature will
exceed 150°C when overtemperature protection is active. Continuous
operation above the specified maximum operating junction temperature
will reduce lifetime.
For more information
www.linear.com/LT8330
3
8330f
LT8330
Typical perForMance characTerisTics
FBX Positive Regulation Voltage
vs Temperature
1.630
1.620
FBX VOLTAGE (V)
FBX VOLTAGE (V)
1.610
1.600
1.590
1.580
1.570
–50 –25
V
IN
= 12V
–0.785
–0.790
EN/UVLO PIN VOLTAGE (V)
–0.795
–0.800
–0.805
–0.810
–0.815
–50 –25
FBX Negative Regulation Voltage
vs Temperature
V
IN
= 12V
1.74
1.72
1.70
1.68
1.66
1.64
1.62
1.60
1.58
1.56
EN/UVLO Pin Thresholds
vs Temperature
V
IN
= 12V
EN/UVLO RISING (TURN-ON)
EN/UVLO FALLING (TURN-OFF)
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G01
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G02
1.54
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G03
Switching Frequency
vs Temperature
2.10
2.08
SWITCHING FREQUENCY (MHz)
2.06
2.04
2.02
2.00
1.98
1.96
1.94
1.92
1.90
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G04
Switching Frequency vs V
IN
2.10
2.05
2.00
1.95
1.90
1.85
NORMALIZED SWITCHING FREQUENCY (%)
2.15
SWITCHING FREQUENCY (MHz)
125
Normalized Switching Frequency
vs FBX Voltage
V
IN
= 24V
V
IN
= 24V
100
75
50
25
0
5
10
15
20 25
V
IN
(V)
30
35
40
45
0
–0.8
–0.4
0.0
0.4
0.8
FBX VOLTAGE (V)
1.2
1.6
8330 G06
8330 G05
Switch Current Limit vs Duty
Cycle
1.40
V
IN
= 12V
MINIMUM ON–TIME (ns)
100
90
SWITCH CURRENT LIMIT (A)
80
70
60
50
40
1.00
0
20
40
60
DUTY CYCLE (%)
80
100
8330 G07
Switch Minimum On-Time
vs Temperature
V
IN
= 24V
60
55
MINIMUM OFF–TIME (ns)
50
45
40
35
Switch Minimum Off-Time
vs Temperature
V
IN
= 24V
1.30
1.20
1.10
30
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G08
30
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G09
4
8330f
For more information
www.linear.com/LT8330
LT8330
Typical perForMance characTerisTics
V
IN
Pin Current (Sleep Mode, Not
Switching) vs Temperature
10.00
8.75
V
IN
PIN CURRENT (µA)
V
IN
PIN CURRENT (µA)
7.50
6.25
5.00
3.75
2.50
1.25
0
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G10
V
IN
Pin Current (Active Mode, Not
Switching) vs Temperature
1000
950
SWITCHING FREQUENCY (MHz)
900
850
800
750
700
650
600
–50 –25
0 25 50 75 100 125 150 175
JUNCTION TEMPERATURE (°C)
8330 G11
Burst Frequency vs Load Current
2.5
FRONT PAGE APPLICATION
V
IN
= 12V
V
OUT
= 48V
V
IN
= 12V
V
IN
= 12V
2.0
1.5
1.0
0.5
0
0
10
20
30
40
LOAD CURRENT (mA)
50
8330 G12
Switching Waveforms
(in CCM)
I
L
500mA/DIV
Switching Waveforms
(in DCM/Light Burst Mode)
Switching Waveforms
(in Deep Burst Mode)
I
L
500mA/DIV
I
L
500mA/DIV
V
SW
20V/DIV
V
SW
20V/DIV
V
SW
20V/DIV
1µs/DIV
FRONT PAGE APPLICATION
V
IN
= 12V, V
OUT
= 48V, I
LOAD
= 20mA
8330 G14
1µs/DIV
FRONT PAGE APPLICATION
V
IN
= 12V, V
OUT
= 48V, I
LOAD
= 135mA
8330 G13
1µs/DIV
FRONT PAGE APPLICATION
V
IN
= 12V, V
OUT
= 48V, I
LOAD
= 2mA
8330 G15
V
OUT
Transient Response: Load
Current Transients from 67.5mA to
135mA to 67.5mA
FRONT PAGE APPLICATION
I
L
100mA/DIV
V
IN
= 12V
V
OUT
= 48V
V
OUT
500mV/DIV
100µs/DIV
8330 G16
V
OUT
Transient Response: Load
Current Transients from 5mA to
135mA to 5mA
FRONT PAGE APPLICATION
I
L
100mA/DIV
V
IN
= 12V
V
OUT
= 48V
V
OUT
500mV/DIV
100µs/DIV
8330 G17
For more information
www.linear.com/LT8330
5
8330f