Datasheet
1 1
7
1 1
IN
COLD HOT
IN IN
HOT COLD
V RCOLD RHOT
V V
R
V V
RHOT RCOLD
V V
é ù
´ ´ ´ -
ê ú
ë û
=
é ù é ù
´ - - ´ -
ê ú ê ú
ë û ë û
TS
TEMP
PACK+
PACK-
+
+
V
HOT
V
COLD
R7
R61
IN
Adapter
R8
Notnecessary
inall
applications
bq240xT
bq24072T
bq24075T, bq24079T
www.ti.com
SLUS937A –DECEMBER 2009–REVISED APRIL 2010
(2)
Where:
V
COLD
= 0.25 X V
IN
V
HOT
= 0.125 X V
IN
RHOT is the expected thermistor resistance at the programmed hot threshold, RCOLD is the expected thermistor
resistance at the programmed cold threshold. If the value of R6 is less than 100kΩ, R3 must be added to protect
the IC from 28V inputs. If R6 is greater than 100kΩ, R8 does not need to be used.
Figure 35. NTC Monitoring Function
For applications that do not require the TS monitoring function, set R6 = 200kΩ and R7 = 49.9kΩ to set the TS
voltage at a valid level and maintain charging.
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