Datasheet

CHARGESUSPENDED CHARGESUSPENDED
TEMPERATURERANGE
TOINITIATECHARGE
TEMPERATURERANGE
DURING A CHARGE
CYCLE
VLTF
VHTF
GND
VTCO
VLTF
GND
VLTFH
VLTFH
VREF
VREF
CHARGESUSPENDED CHARGESUSPENDED
VREF COLD HOT
LTF TCO
VREF VREF
HOT COLD
TCO LTF
1 1
V RTH RTH
V V
RT2 =
V V
RTH 1 RTH 1
V V
æ ö
´ ´ ´ -
ç ÷
è ø
æ ö
æ ö
´ - - ´ -
ç ÷
ç ÷
è ø
è ø
-
VREF
LTF
COLD
V
1
V
RT1 =
1 1
+
RT2 RTH
VREF
TS
RT 2
RT 1
RTH
103 AT
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www.ti.com SLUSA44 –MARCH 2010
Figure 11. TS Pin, Thermistor Sense Thresholds
Assuming a 103AT NTC thermistor is selector, the value RT1 and RT2 can be determined by using the following
equations:
(4)
(5)
Figure 12. TS Resistor Network
CE (Charge Enable)
The CE digital input is used to disable or enable the charge process. A high-level signal on this pin enables
charge, provided all the other conditions for charge are met (see Enabling and Disabling Charge). A high to
low transition on this pin also resets all timers and fault conditions. There is an internal 1 MΩ pulldown resistor on
the CE pin, so if CE is floated the charge will not turn on.
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