LT3991EMSE-3.3#PBF Linear Technology, LT3991EMSE-3.3#PBF Datasheet - Page 3

• Manufacturer Part Number: LT3991EMSE-3.3#PBF
• Description: IC, DC-DC CONV, 2MHz, MSOP10
• Manufacturer: Linear Technology

Specifications of LT3991EMSE-3.3#PBF

• Primary Input Voltage: 55V
• No. Of Outputs: 1
• Output Voltage: 3.3V
• Output Current: 1.2A
• No. Of Pins: 10
• Operating Temperature Range: -40°C To +125°C
• Peak Reflow Compatible (260 C): Yes
• Msl: MSL 1 - Unlimited
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ELECTRICAL CHARACTERISTICS
temperature range, otherwise specifications are at T
PARAMETER
Minimum Input Voltage
Quiescent Current from V
LT3991 FB Pin Current
Internal Feedback Resistor Divider
Feedback Voltage
LT3991-3.3 Output Voltage
LT3991-5 Output Voltage
FB Voltage Line Regulation
Switching Frequency
Minimum Switch On Time
Minimum Switch Off Time
Switch Current Limit
Switch V
Switch Leakage Current
Boost Schottky Forward Voltage
Boost Schottky Reverse Leakage
Minimum Boost Voltage (Note 3)
BOOST Pin Current
EN Voltage Threshold
EN Voltage Hysteresis
EN Pin Current
LT3991 PG Threshold Offset from V
LT3991 PG Hysteresis
LT3991-X PG Threshold Offset from V
LT3991X PG Hysteresis
PG Leakage
PG Sink Current
SYNC Threshold
SYNC Pin Current
SS Source Current
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 LT3991E 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.
CESAT
IN
FB
OUT
CONDITIONS
V
V
V
V
4.3V < V
R
R
R
I
I
V
V
I
EN Rising
V
V
V
V
V
(Note 4)
SW
SH
SW
EN
EN
EN
FB
REVERSE
IN
FB
OUT
PG
PG
SS
T
T
T
= 11k
= 35.7k
= 255k
= 100mA
= 5V
= 1.19V
Rising
Low
High, V
= 1A
= 1A, V
High, V
= 3V
= 0.4V
= 1V
A
Rising
= 25°C. V
IN
= 12V
< 40V (Note 4)
BOOST
SYNC
SYNC
The
Low
Low
l
= 15V
IN
denotes the specifications which apply over the full operating
= 12V, V
The LT3991I is guaranteed over the full –40°C to 125°C operating junction
temperature range. High junction temperatures degrade operating
lifetimes. Operating lifetime is derated at junction temperatures greater
than 125°C.
Note 3: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the switch.
Note 4: Minimum input voltage depends on application circuit.
LT3991/LT3991-3.3/LT3991-5
EN
= 12V, V
BD
= 3.3V unless otherwise noted. (Note 2)
l
l
l
l
l
l
l
l
l
1.175
1.165
3.224
3.25
4.93
4.89
0.95
MIN
160
300
1.6
0.8
1.7
5.5
0.6
0.6
60
0.0002
1.19
1.19
0.02
0.02
1.01
0.02
TYP
200
110
150
440
800
100
570
0.7
1.7
0.1
3.3
3.3
2.3
1.4
0.2
1.3
0.8
0.1
10
25
30
20
4
5
5
2
1
9
1
1.205
1.215
3.376
MAX
3.35
5.07
5.11
0.01
1.07
12.5
240
200
140
4.3
1.2
2.7
4.5
2.4
1.2
2.9
1.8
1.0
1.6
12
33
20
1
1
1
UNITS
3991fa
3
MHz
MHz
%/V
MΩ
kHz
mV
mV
mA
mV
mV
mV
μA
μA
μA
μA
μA
nA
nA
µA
μA
nA
μA
ns
ns
%
%
V
V
V
V
V
V
V
A
V
V
V