Linear Technology LTC 4125, Manual

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LTC4125
4
4125f
For more information www.linear.com/LTC4125
elecTrical characTerisTics
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Input Current Limit and Monitoring
V
IS
+
,IS
– Sense Voltage Offset
l
–500
–1.5
500
1.5
µV
mV
IS
+
Pin Current V
IS
+ = 5V, V
IS
+
,IS
– = –50mV –100 100 nA
IS
–
Pin Current V
IS
– = V
IS
+ = 5V 15 μA
IMON Pin Leakage Current V
IS
+
,IS
– = –50mV, V
IMON
= 0V – 5V –100 100 nA
V
ITH
Input Current Comparator Threshold at IMON
during Search
V
IMON
Rising
l
0.785 0.800 0.815 V
V
ILIM
Input Current Limit Comparator Threshold at
IMON during Delay Time
V
IMON
Rising
l
1.175 1.200 1.225 V
Input Current Limit Comparator Hysteresis 40 mV
Thermistor Input
NTC Hot Threshold V
NTC
Falling, % of V
IN
l
33 35 37 % V
IN
NTC Thresholds Hysteresis % of V
IN
5 % V
IN
NTC Open Circuit Voltage % of V
IN
l
48 50 52 % V
IN
NTC Open Circuit Input Resistance 300 kΩ
Open Drain Status Pin
STAT Pin Leakage Current V
STAT
= 5V –1 1 μA
STAT Pin Output Voltage Low I
STAT
= 1mA
l
0.4 V
The
l
denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= V
IN1
= V
IN2
= 5V unless otherwise noted (Notes 2, 3).
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 LTC4125 is tested under conditions such that T
J
≈ T
A
. The
LTC4125E is guaranteed to meet specifications from 0°C to 85°C junction
temperature. Specifications over the -40°C to 125°C operating junction
temperature are assured by design, characterization and correlation
with statistical process controls. The LTC4125I is guaranteed over the
full -40°C to 125°C operating junction temperature range. 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 following
formula:
T
J
= T
A
+ (P
D
•
θ
JA
), where
θ
JA
(in °C/W) is the package thermal
impedance.
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 impedance and
other environmental factors. This IC includes over temperature protection
that is intended to protect the device during momentary SW MOSFETs
over current situation. Junction temperature will exceed 125°C when over
temperature protection is active. Continuous operation above the specified
maximum operating junction temperature may impair device reliability.
Note 3: All currents into pins are positive; all voltages are referenced to
GND unless otherwise noted.
Note 4: This IC includes overtemperature protection that is intended
to protect the device. Junction temperature will exceed 125°C when
overtemperature protection is active. Continuous operation above the
specified maximum operating junction temperature will reduce lifetime.