LTC4079
4
4079f
For more information www.linear.com/LTC4079
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
NTC Temp Monitor
V
COLD
Low Temp. Fault NTC Threshold Voltage V
NTC
/V
NTCBIAS
l
72.3 73.8 75.3 %
V
HOT
High Temp. Fault NTC Threshold Voltage V
NTC
/V
NTCBIAS
l
35.6 36.6 37.6 %
V
NTC(DIS)
NTC Disable Voltage Threshold V
NTC
l
60 80 100 mV
Pulsed NTCBIAS Voltage 20k from NTCBIAS to Ground 4 V
NTCBIAS Period 3 Sec
NTCBIAS Pulse Width 210 µs
NTC Input Leakage Current V
NTC
= V
NTCBIAS
l
0.1 100 nA
Enable Input (EN)
V
EN(SD)
Shutdown Threshold V
EN
Falling
Hysteresis
l
0.400 0.750
55
1.100 V
mV
V
EN(REG)
Enable Pin Regulation Voltage Minimum V
EN
for Charge Current
l
1.170 1.190 1.210 V
Enable Pin Leakage Current When Pulled High V
EN
= 60V
l
0 20 nA
Status Outputs (CHRG)
Output Low Voltage 1mA Into the Open-Drain Output
l
0.16 0.4 V
Output Leakage Current V
CHRG
= 60V, V
EN
= 0V
l
0.1 100 nA
elecTrical characTerisTics
The l denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at
T
A
= 25°C (Notes 2, 3). V
IN
= 12V, V
BAT
= 7.4V, V
FB
= 1.057V, V
EN
= 12V, R
PROG
= 3k (100mA charge current) unless otherwise specified.
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: Unless otherwise
specified, current into a pin is positive and
current out of a pin is negative.
Note 3:
The LTC4079 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC4079E 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
LTC4079I is guaranteed over the full –40°C to 125°C operating junction
temperature range. 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.
Note 4: BAT pin charge current, PROG pin and feedback divider currents
are excluded from supply quiescent current.
Note 5: Charge current is reduced by thermal regulation as the junction
temperature rises above T
LIM
(118°C).
