Datasheet

LTC3605
3
3605fc
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. Absolute Maximum Ratings are those values beyond
which the life of a device may be impaired.
Note 2: The LTC3605E is guaranteed to meet performance specifications
from 0°C to 85°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3605I is guaranteed over the full
–40°C to 125°C operating temperature range.
Note 3: Dynamic supply current is higher due to the internal gate charge
being delivered at the switching frequency.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
PV
IN
V
IN
Supply Range 4 15 V
I
Q
Input DC Supply Current
Active
Shutdown
(Note 3)
Mode = 0, R
T
= 162k
V
IN
=12V, RUN = 0
2
11
5
40
mA
µA
V
FB
Feedback Reference Voltage ITH =1.2V (Note 4) –40°C to 85°C
ITH
=1.2V (Note 4) –40°C to 125°C
l
l
0.594
0.592
0.600
0.600
0.606
0.608
V
V
DV
FB(LINE)
Feedback Voltage Line
Regulation
V
IN
= 4V to 15V, ITH = 1.2V, –40°C to 85°C
V
IN
= 4V to 15V, ITH = 1.2V, –40°C to 125°C
l
l
0.001
0.04
0.02
0.1
%/V
%/V
DV
FB(LOAD)
Feedback Voltage Load
Regulation
ITH = 0.8V to 1.6V, –40°C to 85°C
ITH = 0.8V to 1.6V, –40°C to 125°C
l
l
0.1
0.1
0.2
0.3
%
%
I
FB
Feedback Pin Input Current ±30 nA
g
m
(EA) Error Amplifier Transconductance ITH = 1.2V 1.15 1.35 1.6 mS
t
ON(MIN)
Minimum On-Time 40 ns
t
OFF(MIN)
Minimum Off-Time 70 ns
I
LIM
Positive Inductor Valley Current Limit V
FB
= 0.57V 5 6 7.5 A
R
TOP
Top Power NMOS On-Resistance INTV
CC
= 3.3V 70 150
mW
R
BOTTOM
Bottom Power NMOS On-Resistance INTV
CC
= 3.3V 35 55
mW
V
UVLO
INTV
CC
Undervoltage Lockout
Threshold
INTV
CC
Falling
INTV
CC
Hysteresis (Rising)
2.4 2.6
0.25
2.8 V
V
V
RUN
Run Threshold 2 (I
Q
= 2mA)
Run Threshold 1 (I
Q
= 400µA)
RUN Rising
RUN Rising
1.2
0.45
1.25
0.6
1.3
0.75
V
V
V
INTVCC
Internal V
CC
Voltage 4V < V
IN
< 15V 3.2 3.3 3.4 V
DV
INTVCC
INTV
CC
Load Regulation I
LOAD
= 0mA to 20mA 0.5 %
OV Output Overvoltage
PGOOD Upper Threshold
V
FB
Rising 7 10 13 %
UV Output Undervoltage
PGOOD Lower Threshold
V
FB
Falling –13 –10 –7 %
DV
FB(HYS)
PGOOD Hysteresis V
FB
Returning 1.5 %
R
PGOOD
PGOOD Pull-Down Resistance 1mA Load 12 25
W
I
PGOOD
PGOOD Leakage 0.54V < V
FB
< 0.66V 2 µA
I
TRACK/SS
TRACK Pull-Up Current 2.5 4 µA
f
OSC
Oscillator Frequency R
T
= 162k
l
0.85 1 1.2 MHz
CLKIN CLKIN Threshold 0.7 V
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C.
Note 4: The LTC3605 is tested in a feedback loop that adjusts V
FB
to
achieve a specified error amplifier output voltage (ITH).
Note 5: T
J
is calculated from the ambient temperature T
A
and
power dissipation as follows: T
J
= T
A
+ P
D
• (37°C/W). See Thermal
Considerations section.
Note 6: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.