RT5016C_16 Datasheet, PDF (42/68 Pages) Richtek Technology Corporation – I2C Programmable Multi-Channel PMU

RT5016C
Battery Pack Temperature Monitoring
The battery pack temperature monitoring function can be realized by connecting the TS pin to an external Negative
Temperature Coefficient (NTC) thermal resistor to prevent over temperature condition. Charging is suspended when the
voltage at the TS pin is out of normal operating range. The internal timer is then paused, but the value is maintained.
When the TS pin voltage returns to normal operating range, charging will resume and the safe charge timer will continue
to count down from the point where it was suspended. Note that although charging is suspended due to the battery pack
temperature fault, the CHG pin will flash at 0.5Hz and indicate charging.
The 3.3V at the VP pin is buffered by the RT5016C once it is in charging state or its PMU part is enabled. If a 100kΩ
NTC thermal resistor is used, the A0.TSSEL bit should be set to “1”. If a 10kΩ NTC thermal resistor is used, the
A0.TSSEL bit should be set to “0”. The TSSEL bit determines the TS threshold levels for 0°C and 60°C. It also defines
the TS threshold levels used in JEITA operation. The choosing method of R1 and R2 to meet battery temperature
monitoring shows as below.
Case 1 : TSSEL = H (For 100kΩ NTC) :
Case 2 : TSSEL = L (For 10kΩ NTC) :
VP
VP
R1
TS
R2
0.74 x VP _-
+
-
+
0.28 x VP
Too Cold
Too Hot
R_NTC
Figure 4
Too Cold Temperature
R_COLD = R_NTC
Too Hot Temperature
R_HOT = R_NTC
R2  R_COLD
R_COLD  R1 R2
= 0.74
--------------------------------------- (1)
R2  R_HOT
R_HOT  R1 R2
= 0.28 ----------------------------------------- (2)
Form (1), (2)
R1 =
R_COLD  R_HOT
2.457
R2 = 0.389 R1 R_HOT
If R2 < 0
R_COLD
R_COLD  R1
=
0.74
---------------------------------------------- (3)
Form (3)
R1 =
R_COLD
0.74
 R_COLD
VP
VP
R1
TS
R2
0.6 x VP _-
+
-
+
0.28 x VP
Too Cold
Too Hot
R_NTC
Figure 5
Too Cold Temperature
R_COLD = R_NTC
Too Hot Temperature
R_HOT = R_NTC
R2 + R_COLD
R_COLD +R1+R2
= 0.6
------------------------------------------ (1)
R2 + R_HOT
R_HOT +R1+R2
= 0.28
------------------------------------------ (2)
Form (1), (2)
R1 = 0.9  R_COLD  R_HOT 
R2 = 0.388 R1 R_HOT
If R2 < 0
R_{COLD = 0.6 ------------------------------------------------- (3)}
R_COLD +R1
Form (3)
R1 =
R_COLD
0.6
 R_COLD
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DS5016C-02 November 2016