Datasheet

Functional description STC3115
12/31 DocID023755 Rev 4
6.1.3 Internal temperature monitoring
The chip temperature (close to the battery temperature) is measured using one conversion
cycle of the A/D converter every 16 s.
The conversion cycle takes 2
13
= 8192 clock cycles. Using the 32768 Hz internal clock, the
conversion cycle time is 250
ms. Resolution is 1° C and range is -40 to +125 °C.
The result is stored in the REG_TEMPERATURE register (see Table 12).
6.1.4 Current sensing
Voltage drop across the sense resistor is integrated during a conversion period and input to
the 14-bit sigma-delta A/D converter.
Using the 32768 Hz internal clock, the conversion cycle time is 500 ms for a 14-bit
resolution. The LSB value is 5.88
µV. The A/D converter output is in two’s complement
format.
When a conversion cycle is completed, the result is added to the Coulomb counter
accumulator and the number of conversions is incremented in a 16-bit counter.
The current register is updated only after the conversion closest to the voltage conversion
(that is: once per 4-s measurement cycle). The result is stored in the REG_CURRENT
register (see
Table 12).