Rainbow Electronics MAX1874 - Manual (Page 5)

MAX1874
Dual-Input, USB/AC Adapter, 1-Cell
Li+ Charger with OVP and Thermal Regulation
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ELECTRICAL CHARACTERISTICS (continued)
(V USB = V DC = V DCLV = V EN = V USEL = 5V, V BATT = 4.2V, V THRM = V REF / 2, Circuit of Figure 2, T A = -40°C to +85°C, unless otherwise
noted. Typical values are at T A = +25°C.) (Note 4)
PARAMETER CONDITIONS MIN TYP MAX UNITS
BATTERY VOLTAGE
BATT Regulation Voltage 4.1685 4.2315 V
BATT Prequal Voltage Threshold BATT rising 2.8 3.2 V
REF Voltage (Buffered Output)
I REF = 0 to 500µA, 4V < V DC or V USB < 6.5V;
does not affect BATT regulation accuracy
2.94 3.06 V
BATTERY CHARGING AND PRECHARGE CURRENT
DCI Voltage Range 0.1 x V REF V REF V
V DCI = V REF 930 1070
DCI Voltage to BATT Current
V DCI = V REF / 2 490 565
mA
USEL = high 495
USB Charging Current
USEL = low 95
mA
Prequal Charging Current V BATT = 2.5V 40 70 mA
BATT Input Current No DC or USB power, V BATT = 4.2V 7.5 µA
BATT Shutdown Current EN = GND, USB and/or DC powered 2 µA
THERMISTOR MONITOR AND DIE-TEMPERATURE REGULATION
THRM COLD Trip Level (Note 2) 0.72 0.76 V REF
THRM HOT Trip Level (Note 2) 0.28 0.30 V REF
THRM Disable Threshold 50 150 mV
LOGIC INPUT/OUTPUTS AND GATE DRIVERS
DCOK Off-Leakage Current V DCOK = 12V, V DC = 0V 1 µA
UOK Off-Leakage Current V UOK = 6.5V 1 µA
DC input (% of charge current set at DCI) 8 20
CHG Threshold to Indicate Battery Full,
Battery Current Falling (Note 3)
USB input, USEL = 5V
(% of USB charging current)
20 30
%
CHG Logic-Low Output Sinking 10mA sink 0.4 V
CHG Leakage Current V CHG = 6.5V 1 µA
EN, USEL Logic-Input High Level 1.6 V
EN, USEL Logic-Input Low Level 0.4 V
EN, USEL Input Bias Current 1 µA
Note 1: BYP internally connects to the active power input (DCLV or USB). DCLV takes priority if both inputs are powered.
Note 2: These limits guarantee +5°C accuracy with 5% accuracy of thermistor beta (3450 nominal) with 2°C of hysteresis.
Note 3: The CHG output does not go high unless charge current is below the indicated threshold (as set by DCI) and the charger is in
voltage-mode operation. In 100mA USB mode, CHG goes high when the charger transitions from current to voltage mode.
Note 4: Specifications to -40°C are guaranteed by design, not production tested.