LTC4060_15 Datasheet, PDF (4/20 Pages) Linear Technology – Standalone Linear NiMH/NiCd Fast Battery Charger

LTC4060
ELECTRICAL CHARACTERISTICS The ● indicates specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_CC = 5V, V_BAT = 2.8V, GND = 0V unless otherwise specified. All
currents into the device pins are positive and all currents out of the device pins are negative. All voltages are referenced to GND
unless otherwise specified.
SYMBOL PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
V_HTIH NTC Pin Hot Charge Initiation Hysteresis Voltage V_NTC Increasing
100
mV
V_HTC
NTC Pin Hot Charge Cutoff Threshold Voltage
V_NTC Decreasing, 4.5V ≤ V_CC ≤ 10V
● 0.37 •
0.4 •
0.43 •
V
V_CC
V_CC
V_CC
V_HTCH NTC Pin Hot Charge Cutoff Hysteresis Voltage
V_NTC Increasing
100
mV
V_NDIS NTC Pin Disable Threshold Voltage
25
250
mV
I_NL
NTC Pin Pull-Down Current
V_NTC = 2.5V
● 0.15
1.5
µA
t_ACC
Timer Accuracy
R_PROG = 698Ω, C_TIMER = 1.2nF and
R_PROG = 3480Ω, C_TIMER = 470pF
–15
0
15
%
Output Drivers
I_DRV
Drive Pin Sink Current
V_DRIVE = 4V
● 40
70
120
mA
R_DRV
Drive Pin Resistance to V_CC
V_DRIVE = 4V, Not Charging
4700
Ω
V_OL
ACP, CHRG Output Pins Low Voltage
I_ACP = I_CHRG = 10mA
0.8
V
I_OH
ACP, CHRG Output Pins High Leakage Current Outputs Inactive, V_CHRG = V_ACP = V_CC
–2
2
µA
Control Inputs
V_IT
SHDN, SEL0, SEL1, CHEM, PAUSE Pins Digital V_CC = 10V
Input Threshold Voltage
350
650
mV
V_ITH
SHDN, SEL0, SEL1, CHEM, PAUSE Pins Digital
Input Hysteresis Voltage
50
mV
I_IPD
SHDN, SEL0, SEL1, CHEM Pins Digital Input
V_CC = 10V, V_IN = V_CC
Pull-Down Current
0.4
2
µA
I_IPU
PAUSE Pin Digital Input Pull-Up Current
V_IN = GND
–2
–0.4
µA
Note 1: Absolute Maximum Ratings only indicate limits for survivability.
Operating the device beyond these limits may result in permanent damage.
Continuous or extended application of these maximum levels may
adversely affect device reliability.
Note 2: The LTC4060 is guaranteed to meet performance specifications
from 0°C to 70°C ambient temperature range and 0°C to 85°C junction
temperature range. Specifications over the –40°C to 85°C operating
ambient temperature range are assured by design, characterization and
correlation with statistical process controls.
Note 3: This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. Overtempera-
ture protection is activated at a temperature of approximately 145°C,
which is above the specified maximum operating junction temperature.
Continuous operation above the specified maximum operation temperature
may result in device degradation or failure. Operating junction temperature
T_J (in °C) is calculated from the ambient temperature T_A and the average
power dissipation P_D (in watts) by the formula:
T_J = T_A + θ_JA • P_D
Note 4: Short duration drops below the minimum V_CC specification of
several microseconds or less are ignored by the undervoltage detection
circuit.
Note 5: Assumes that the external PNP pass transistor has negligible B-C
reverse leakage current when the collector is biased at 2.8V (V_BAT for two
charged cells in series) and the base is biased at V_CC.
Note 6: Assumes that the external PNP pass transistor has negligible B-E
reverse leakage current when the emitter is biased at 0V (V_CC) and the
base is biased at 5.6V (V_BAT for four charged cells in series).
Note 7: The charge current specified is the regulated current through the
internal current sense resistor that flows into the external PNP pass
transistor’s emitter. Actual battery charging current is slightly less and
depends upon PNP alpha.
Note 8: Given as a per cell voltage (V_BAT/Number of Cells).
Note 9: Supply current includes the current programming resistor current
of 2mA. The charger is paused and not charging the battery.
Note 10: The minimum V_CC supply is set at 5V during this test to
compensate for voltage drops due to test socket contact resistance and 2A
of current. This ensures that the supply voltage delivered to the device
under test does not fall below the UVLO entry threshold. Specification at
the minimum V_CC of 4.5V is assured by design and characterization.
4060f
4