Range (Notes 3, 6) ................................. –55°C to 150°C
Storage Temperature Range .................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MSE Only .......................................................... 300°C
PIN CONFIGURATION
TOP VIEW
C
+
V
OUT
FB
SHUNT
PGOOD
1
2
3
4
5
11
GND
10 V
IN
9 C
–
8 GND
7 BIAS
6 EN
TOP VIEW
V
OUT
FB
SHUNT
PGOOD
C
+
1
2
3
4
5
11
GND
10
9
8
7
6
V
IN
C
–
GND
BIAS
EN
DD PACKAGE
10-LEAD (3mm
×
3mm) PLASTIC DFN
T
JMAX
= 150°C,
θ
JA
= 43°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
MSE PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 40°C/W
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
LTC3255EDD#PBF
LTC3255IDD#PBF
LTC3255HDD#PBF
LTC3255MPDD#PBF
LTC3255EMSE#PBF
LTC3255IMSE#PBF
LTC3255HMSE#PBF
LTC3255MPMSE#PBF
TAPE AND REEL
LTC3255EDD#TRPBF
LTC3255IDD#TRPBF
LTC3255HDD#TRPBF
LTC3255MPDD#TRPBF
LTC3255EMSE#TRPBF
LTC3255IMSE#TRPBF
LTC3255HMSE#TRPBF
LTC3255MPMSE#TRPBF
PART MARKING*
LGHD
LGHD
LGHD
LGHD
LTGHF
LTGHF
LTGHF
LTGHF
PACKAGE DESCRIPTION
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead (3mm
×
3mm) Plastic DFN
10-Lead Plastic MSOP
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 150°C
–55°C to 150°C
–40°C to 125°C
–40°C to 125°C
–40°C to 150°C
–55°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 nonstandard 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/
3255f
2
For more information
www.linear.com/LTC3255
LTC3255
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 12V unless otherwise noted. (Notes 2, 3)
SYMBOL
V
IN
V
OUT
V
UVLO_BK
V
UVLO_SH
I
VIN
PARAMETER
Input Voltage Range (Note 7)
Output Voltage Range
V
IN
Undervoltage Lockout Threshold
with Shunt Disabled
V
IN
Undervoltage Lockout Threshold
with Shunt Enabled
V
IN
Quiescent Current
EN Low
EN High, SHUNT = GND
EN High, SHUNT = BIAS
Available Output Current
Shunt Disabled
Shunt Enabled
Regulated Feedback Voltage
FB Pin Leakage
EN High Level Input Voltage
EN Low Level Input Voltage
EN Pin Input Current
V
OUT
Current Limit
Oscillator Frequency
PGOOD Rising Threshold
PGOOD Output Low Voltage
PGOOD High Impedance Leakage
% of Final Regulation Voltage
I
PGOOD
= 200µA
V
PGOOD
= 12V
l
l
ELECTRICAL CHARACTERISTICS
CONDITIONS
l
l
MIN
4
2.4
TYP
MAX
48
12.5
UNITS
V
V
V
mV
V
mV
µA
µA
µA
mA
mA
V
IN
Rising, SHUNT = GND
Hysteresis, SHUNT = GND
V
IN
Rising, SHUNT= BIAS
Hysteresis, SHUNT= BIAS
Shutdown
Enabled, Output in Regulation
Enabled, Output in Regulation
SHUNT = GND
SHUNT = BIAS, I
VIN
= 4mA, V
OUT
= 3.3V
V
FB
= 1.3V
l
l
l
l
l
2.4
50
5
200
3
16
30
50
7.4
1.176
1.4
2.7
5.7
6
35
45
I
VOUT
V
FB
I
FB
V
EN_VIH
V
EN_VIL
I
EN
I
LIM
f
OSC
V
PGTHRESH
V
PG(LOW)
7.8
1.200
1.224
±10
0.4
0
0
120
500
±1
±1
V
nA
V
V
µA
µA
mA
kHz
V
EN
= 12V
V
EN
= 0V
90
94
0.1
98
0.4
1
%
V
µA
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:
All voltages are referenced to GND unless otherwise specified.
Note 3:
The LTC3255E is guaranteed to meet performance specifications
from 0°C to 85°C operating 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 LTC3255I is guaranteed over the –40°C to 125°C operating junction
temperature range. The LTC3255H is guaranteed over the –40°C to 150°C
operating junction temperature range. The LTC3255MP is guaranteed over
the –55°C to 150°C operating junction temperature range. High junction
temperatures degrade operating lifetimes; operating lifetime is derated
for junction temperatures greater than 125°C. Note that the maximum
ambient temperature consistent with these specifications is determined by
specific operating conditions in conjunction with board layout, the rated
package thermal resistance and other environmental factors.
The junction temperature (T
J
, in °C) is calculated from the ambient
temperature (T
A
, in °C) and power dissipation (P
D
, in Watts) according to
the formula:
T
J
= T
A
+ (P
D
•
θ
JA
)
where
θ
JA
(in °C/W) is the package thermal impedance.
Note 4:
The LTC3255 has an internal diode that conducts whenever V
OUT
is pulled below GND. When so pulled, absolute maximum current out of
V
OUT
is 50mA.
Note 5:
The LTC3255 has an internal diode that conducts whenever
PGOOD is pulled below GND. When so pulled, absolute maximum current
out of PGOOD is 100µA.
Note 6:
This IC has overtemperature protection that is intended to protect
the device during momentary overload conditions. Junction temperatures
will exceed 150°C when overtemperature protection is active. Continuous
operation above the specified maximum operating junction temperature
may impair device reliability.
Note 7:
This IC has input overvoltage protection that shuts down the
device whenever V
IN
exceeds the specified input voltage range. Shutdown
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