PG, BD Voltage .........................................................30V
Operating Junction Temperature Range (Note 2)
LT3990E ............................................. –40°C to 125°C
LT3990I .............................................. –40°C to 125°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MS Only ............................................................ 300°C
PIN CONFIGURATION
TOP VIEW
FB 1
EN 2
V
IN
3
GND 4
GND 5
11
10 RT
9
8
7
6
PG
BD
BOOST
SW
FB
EN
V
IN
GND
GND
1
2
3
4
5
TOP VIEW
10
9
8
7
6
RT
PG
BD
BOOST
SW
DDB PACKAGE
10-LEAD (3mm 2mm) PLASTIC DFN
θ
JA
= 76°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
MS PACKAGE
10-LEAD PLASTIC MSOP
θ
JA
= 100°C/W
ORDER INFORMATION
LEAD FREE FINISH
LT3990EDDB#PBF
LT3990IDDB#PBF
LT3990EMS#PBF
LT3990IMS#PBF
TAPE AND REEL
LT3990EDDB#TRPBF
LT3990IDDB#TRPBF
LT3990EMS#TRPBF
LT3990IMS#TRPBF
PART MARKING*
LFCZ
LFCZ
LTFDB
LTFDB
PACKAGE DESCRIPTION
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 125°C
–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 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/
3990p
2
LT3990
ELECTRICAL CHARACTERISTICS
PARAMETER
Minimum Input Voltage
Quiescent Current from V
IN
V
EN
Low
V
EN
High
V
EN
High
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V, V
BD
= 3.3V unless otherwise noted. (Note 2)
CONDITIONS
l
MIN
TYP
4
0.7
1.7
MAX
4.2
0.98
2.7
3.5
1.225
1.235
20
0.01
2.64
960
240
865
500
2
2
2
1.8
8
30
1.05
160
1
UNITS
V
μA
μA
μA
V
V
nA
%/V
MHz
kHz
kHz
mA
mA
mV
μA
mV
μA
mV
μA
V
mA
nA
V
mV
mV
mV
μA
μA
ns
l
l
l
Feedback Voltage
FB Pin Bias Current (Note 3)
FB Voltage Line Regulation
Switching Frequency
4.2V < V
IN
< 60V
R
T
= 41.2k, V
IN
= 6V
R
T
= 158k, V
IN
= 6V
R
T
= 768k, V
IN
= 6V
V
IN
= 5V, V
FB
= 0V
V
IN
= 5V
I
SW
= 200mA
I
SCH
= 100mA, V
IN
= V
BD
= NC
V
SW
= 12V
I
SCH
= 50mA, V
IN
= NC, V
BOOST
= 0V
V
REVERSE
= 12V
V
IN
= 5V
I
SW
= 200mA, V
BOOST
= 15V
V
EN
= 12V
EN Rising, V
IN
≥ 4.2V
V
FB
Rising
V
PG
= 3V
V
PG
= 0.4V
V
IN
= 10V
1.195
1.185
1.21
1.21
0.1
0.0002
1.76
640
160
535
350
2.25
800
200
700
400
300
0.05
650
0.05
875
0.02
Switch Current Limit
Catch Schottky Current Limit
Switch V
CESAT
Switch Leakage Current
Catch Schottky Forward Voltage
Catch Schottky Reverse Leakage
Boost Schottky Forward Voltage
Boost Schottky Reverse Leakage
Minimum Boost Voltage (Note 4)
BOOST Pin Current
EN Pin Current
EN Voltage Threshold
EN Voltage Hysteresis
PG Threshold Offset from Feedback Voltage
PG Hysteresis
PG Leakage
PG Sink Current
Minimum Switch On-Time
Minimum Switch Off-Time
l
1.4
5.5
1
l
0.95
80
1
30
120
12
0.01
l
l
40
80
90
100
160
ns
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:
The LT3990E 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
LT3990I is guaranteed over the full –40°C to 125°C operating junction
temperature range.
Note 3:
Bias current flows into the FB pin.
Note 4:
This is the minimum voltage across the boost capacitor needed to
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