DS2781
RESULT REGISTERS
The DS2781 processes measurement and cell characteristics on a 440ms interval and yields seven result
registers. The result registers are sufficient for direct display to the user in most applications. The host system can
produce customized values for system use, or user display by combining measurement, result and User EEPROM
values.
FULL(T) [ ]: The Full capacity of the battery at the present temperature is reported normalized to the 40°C Full
value. This 15-bit value reflects the cell stack model Full value at the given temperature. FULL(T) reports values
between 100% and 50% with a resolution of 61ppm (precisely 2-14). Though the register format permits values
greater than 100%, the register value is clamped to a maximum value of 100%.
Active Empty, AE(T) [ ]: The Active Empty capacity of the battery at the present temperature is reported
normalized to the 40°C Full value. This 13-bit value reflects the cell stack model Active Empty at the given
temperature. AE(T) reports values between 0% and 49.8% with a resolution of 61ppm (precisely 2-14).
Standby Empty, SE(T) [ ]: The Standby Empty capacity of the battery at the present temperature is reported
normalized to the 40°C Full value. This 13-bit value reflects the cell stack model Standby Empty value at the
current temperature. SE(T) reports values between 0% and 49.8% with a resolution of 61ppm (precisely 2-14).
Remaining Active Absolute Capacity (RAAC) [mAh]: RAAC reports the capacity available under the current
temperature conditions at the Active Empty discharge rate (IAE) to the Active Empty point in absolute units of milli-
amp-hours. RAAC is 16 bits. See Figure 14.
Figure 14. Remaining Active Absolute Capacity Register Format
RAAC
Read Only
21 20
MSB—Address 02h
215 214 213 212 211 210 29
MSb
LSB—Address 03h
25 24 23 22
28
27
26
LSb
MSb
LSb
Units:1.6mAhr
Remaining Standby Absolute Capacity (RSAC) [mAh]: RSAC reports the capacity available under the current
temperature conditions at the Standby Empty discharge rate (ISE) to the Standby Empty point capacity in absolute
units of milli-amp-hours. RSAC is 16 bits. See Figure 15.
Figure 15. Remaining Standby Absolute Capacity Register Format
RSAC
Read Only
21 20
MSB—Address 04h
215 214 213 212 211 210 29
MSb
LSB—Address 05h
25 24 23 22
28
27
26
LSb
MSb
LSb
Units:1.6mAhr
17 of 31
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
