lt3990 Linear Technology Corporation, lt3990 Datasheet - Page 3

• Manufacturer Part Number: lt3990
• Description: 60v, 350ma Step-down Regulator With 2.5?a Quiescent Current And Integrated Diodes
• Manufacturer: Linear Technology Corporation

elecTrical characTerisTics
temperature range, otherwise specifications are at T
PARAMETER
Minimum Input Voltage
Quiescent Current from V
Feedback Voltage
FB Pin Bias Current (Note 3)
FB Voltage Line Regulation
Switching Frequency
Switch Current Limit
Catch Schottky Current Limit
Switch V
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/UVLO Pin Current
EN/UVLO Voltage Threshold
EN/UVLO Voltage Hysteresis
PG Threshold Offset from Feedback Voltage
PG Hysteresis as % of Output Voltage
PG Leakage
PG Sink Current
Minimum Switch On-Time
Minimum Switch Off-Time
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.
CESAT
IN
CONDITIONS
V
V
V
4.2V < V
R
R
R
V
V
I
I
V
I
V
V
I
V
EN/UVLO Rising, V
V
V
V
V
SW
SCH
SCH
SW
EN/UVLO
EN/UVLO
EN/UVLO
T
T
T
IN
IN
SW
REVERSE
IN
EN/UVLO
FB
PG
PG
IN
= 158k, V
= 768k, V
= 41.2k, V
= 5V, V
= 5V
= 5V
= 10V
= 200mA
= 200mA, V
Rising
= 3V
= 0.4V
A
= 100mA, V
= 12V
= 50mA, V
= 25°C. V
IN
Low
High
High
= 12V
= 12V
FB
< 40V
The
IN
IN
IN
= 0V
= 6V
= 6V
IN
= 6V
BOOST
IN
l
IN
= NC, V
IN
= V
denotes the specifications which apply over the full operating
= 12V, V
≥ 4.2V
= 15V
BD
Note 3: Bias current flows into the FB pin.
Note 4: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the switch.
= NC
BOOST
BD
= 0V
= 3.3V unless otherwise noted. (Note 2)
l
l
l
l
l
l
l
l
1.195
1.185
1.84
1.14
MIN
672
168
535
360
6.5
30
0.0002
1.21
1.21
0.05
0.05
0.02
1.21
0.01
TYP
840
210
700
440
210
725
900
120
100
0.7
1.7
0.1
2.3
1.4
8.5
1.0
32
10
80
4
1
1.225
1.235
1008
MAX
0.01
2.76
1.28
13.5
252
865
520
160
4.2
1.2
2.7
1.8
20
12
30
LT3990
4
2
2
2
1
UNITS

3990p
MHz
%/V
kHz
kHz
mA
mA
mV
mV
mV
mA
mV
µA
µA
µA
nA
µA
µA
µA
nA
µA
µA
ns
ns
%
%
V
V
V
V
V