, RT Voltage ....................................................6V
PG, BD Voltage .........................................................30V
Operating Junction Temperature Range (Note 2)
LT3970E/LT3970E-X ........................... –40°C to 125°C
LT3970I/LT3970I-X ............................ –40°C to 125°C
LT3970H-X ......................................... –40°C to 150°C
Storage Temperature Range................... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MS Only ............................................................ 300°C
PIN CONFIGURATION
TOP VIEW
*FB/V
OUT
1
EN 2
V
IN
3
GND 4
GND 5
11
GND
10 RT
9 PG
8 BD
7 BOOST
6 SW
*FB/V
OUT
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
*FB for LT3970, V
OUT
for LT3970-3.3, LT3970-5.
ORDER INFORMATION
LEAD FREE FINISH
LT3970EDDB#PBF
LT3970IDDB#PBF
LT3970EMS#PBF
LT3970IMS#PBF
LT3970EDDB-3.3#PBF
LT3970IDDB-3.3#PBF
LT3970EMS-3.3#PBF
LT3970IMS-3.3#PBF
LT3970HMS-3.3#PBF
LT3970EDDB-5#PBF
LT3970IDDB-5#PBF
LT3970EMS-5#PBF
LT3970IMS-5#PBF
LT3970HMS-5#PBF
TAPE AND REEL
LT3970EDDB#TRPBF
LT3970IDDB#TRPBF
LT3970EMS#TRPBF
LT3970IMS#TRPBF
LT3970EDDB-3.3#TRPBF
LT3970IDDB-3.3#TRPBF
LT3970EMS-3.3#TRPBF
LT3970IMS-3.3#TRPBF
LT3970HMS-3.3#TRPBF
LT3970EDDB-5#TRPBF
LT3970IDDB-5#TRPBF
LT3970EMS-5#TRPBF
LT3970IMS-5#TRPBF
LT3970HMS-5#TRPBF
PART MARKING*
LFCZ
LFCZ
LTFDB
LTFDB
LFQH
LFQH
LTFQG
LTFQG
LTFQG
LFQF
LFQF
LTFQD
LTFQD
LTFQD
PACKAGE DESCRIPTION
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead Plastic MSOP
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead (3mm
×
2mm) Plastic DFN
10-Lead Plastic MSOP
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
–40°C to 125°C
–40°C to 125°C
–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 125°C
–40°C to 125°C
–40°C to 150°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/
3970fa
2
LT3970/LT3970-3.3/LT3970-5
ELECTRICAL CHARACTERISTICS
PARAMETER
Minimum Input Voltage
Quiescent Current from V
IN
V
EN
Low
V
EN
High
V
EN
High, –40°C to 125°C
V
EN
High, –40°C to 150°C
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
1.2
2.7
3.5
4
1.225
1.235
3.34
3.366
3.366
5.06
5.1
5.1
20
0.01
2.64
960
240
865
500
2
2
2
1.8
10
30
1.06
1.07
160
13.5
1
UNITS
V
μA
μA
μA
μA
V
V
V
V
V
V
V
V
nA
%/V
MHz
kHz
kHz
mA
mA
mV
μA
mV
μA
mV
μA
V
mA
nA
V
V
mV
mV
mV
%
%
μA
μA
ns
l
l
l
LT3970 Feedback Voltage
LT3970-3.3 Output Voltage
–40°C to 125°C
–40°C to 150°C
LT3970-5 Output Voltage
–40°C to 125°C
–40°C to 150°C
LT3970 FB Pin Bias Current (Note 3)
FB/Output Voltage Line Regulation
Switching Frequency
V
FB
= 1.21V
4.2V < V
IN
< 40V
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
EN Rising, V
IN
≥ 4.2V
V
FB
Rising
V
FB
Rising
V
PG
= 3V
V
PG
= 0.4V
V
IN
= 10V
1.195
1.185
3.26
3.234
3.217
4.94
4.9
4.875
1.21
1.21
3.3
3.3
3.3
5
5
5
0.1
0.0002
l
l
l
l
l
1.76
640
160
535
350
2.25
800
200
700
400
175
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
LT3970 EN Voltage Threshold
LT3970-X EN Voltage Threshold
EN Voltage Hysteresis
LT3970 PG Threshold Offset from Feedback Voltage
LT3970 PG Hysteresis
LT3970-X PG Threshold Offset from Output Voltage
LT3970-X PG Hysteresis as % of Output Voltage
PG Leakage
PG Sink Current
Minimum Switch On-Time
Minimum Switch Off-Time
l
1.4
7
1
l
l
0.94
0.93
80
6.5
1
1
30
120
12
10
1.0
0.01
l
l
30
80
90
100
160
ns
3970fa
3
LT3970/LT3970-3.3/LT3970-5
ELECTRICAL CHARACTERISTICS
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 LT3970E 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
LT3970I is guaranteed over the full –40°C to 125°C operating junction
temperature range. The LT3970H 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 3:
Bias current flows into the FB pin.
Note 4:
This is the minimum voltage across the boost capacitor needed to