ISL6295 Datasheet, PDF (14/25 Pages) Intersil Corporation – Low Voltage Fuel Gauge

ISL6295
General Purpose SRAM
32 bytes of General Purpose SRAM are provided as
temporary storage and is located in Bank 1 at 1:0x000
through 1:0x01F. The RAM may be read or written using
either the Byte or Block transfer modes.
Operational Registers
The following is a detailed description of all registers within
the ISL6295 including all control, status and result bits, and
fields that are contained therein.
DCA - DISCHARGE COUNT ACCUMULATOR
The DCA is a 32-bit register that holds the total accumulated
current discharged from the battery. While current
accumulation is enabled, the DCA is updated every 0.5s by
adding the magnitude of the latest current conversion result
to the previous accumulated value as long as the sign bit of
the lres register is ‘1’, indicating a discharge condition. When
the sign bit is ‘0’, no accumulation is performed by the DCA.
The DCA register will rollover if it is allowed be updated
beyond 0xFFFFFFFF, so proper register maintenance by the
host system is necessary. The DCA register may be cleared
by setting the "CLR0" bit in the ACCclr register.
DTC - DISCHARGE TIME COUNT REGISTER
The DTC records the length of time that the battery is in a
discharge condition. This register is incremented at a rate of
2Hz for as long as current accumulation is enabled and the
sign bit of the Ires register returns a ‘1’ following a current
conversion.
Time accumulation in the DTC register is not expected to
rollover over the life of the battery pack. If desired, the DTC
register may be cleared by setting the “CLR1” bit in the
ACCclr register.
CCA - CHARGE COUNT ACCUMULATOR
The CCA is a 32-bit register that holds the total accumulated
charging current delivered to the battery. While current
accumulation is enabled, the CCA is updated every 0.5s by
adding the magnitude of the latest current conversion result
to the previous accumulated value as long as the sign bit of
the lres register is ‘0’, indicating a charge condition. When
the sign bit is ‘1’, no accumulation is performed by the CCA.
The CCA register will rollover if it is allowed to be updated
beyond 0xFFFFFFFF, so proper register maintenance by the
host system is necessary. The CCA register may be cleared
by setting the "CLR2" bit in the ACCclr register.
CTC - CHARGE TIME COUNT REGISTER
The CTC records the length of time that the battery is in a
charge condition. This register is incremented at a rate of
2Hz for as long as current accumulation is enabled and the
sign bit of the Ires register returns a ‘0’ following a current
conversion.
Time accumulation in the CTC register is not expected to
rollover over the life of the battery pack. If desired, the CTC
register may be cleared by setting the “CLR3” bit in the
ACCclr register.
TA - TEMPERATURE ACCUMULATOR
TA is the accumulated 32-bit value of temperature
measurements from the internal or external temperature
sensor. TA is updated by the Itres or Etres register. Selection
of the internal temperature sensor or external thermistor for
temperature accumulation is made through the “tsel” bit in
the AccumCtrl register.
The TA register will rollover if it is allowed be updated
beyond 0xFFFFFFFF, so proper register maintenance by the
host system is necessary. The TA register may be cleared by
setting the "CLR4" bit in the ACCclr register.
TAT - TEMPERATURE TIME COUNT REGISTER
The TAT register records the length of time that the ISL6295
is sensing temperature and accumulating the value in
register TA. TAT is incremented at a rate of 2Hz for as long
as temperature accumulation is enabled.
Time accumulation in the TAT register is not expected to
rollover over the life of the battery pack. If desired, the TAT
register may be cleared by setting the “CLR5” bit in the
ACCclr register.
14
FN9074.0
October 25, 2005