Rainbow Electronics DS2784 - Manual (Page 25)

DS2784: 1-Cell Stand-Alone Fuel Gauge IC with Li+ Protector and SHA-1 Authentication
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Calculation of Results
RAAC [mAh] = (ACR[mVh] - AE(T) * FULL40[mVh]) * RSNSP [mhos]
Note: RSNSP = 1/RSNS
RSAC [mAh] = (ACR[mVh] - SE(T) * FULL40[mVh]) * RSNSP [mhos]
Note: RSNSP = 1/RSNS
RARC
[%] = 100% * (ACR[mVh] - AE(T) * FULL40[mVh]) /
{(AS * FULL(T) - AE(T)) * FULL40[mVh]}
RSRC
[%] = 100%* (ACR[mVh] - SE(T) * FULL40[mVh]) /
{(AS * FULL(T) - SE(T)) * FULL40[mVh]}
SPECIAL FEATURE REGISTER FORMAT
All register bits are read and write accessible, with default values specified in each bit definition.
ADDRESS 15H
BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0
X X X X X X X PIOB
PIOB —PIO Pin Sense and Control Bit. Writing a 0 to the PIOB bit activates the PIO pin open-drain output driver,
forcing the PIO pin low. Writing a 1 to PIOB disables the output driver, allowing the PIO pin to be pulled high or
used as an input. Reading PIOB returns the logic level forced on the PIO pin. Note that if the PIO pin is left floating
with PIOB set, a weak pulldown current source pulls the PIO pin to V
SS
. PIOB is set to a 1 on power-up. PIOB is
also set in Sleep mode to ensure the PIO pin is high-impedance in sleep mode.
Note:
Do not write PIOB to 0 if PSPIO is enabled.
X —Reserved Bits.
EEPROM REGISTER
The EEPROM register provides access control of the EEPROM blocks. EEPROM blocks can be locked to prevent
alteration of data within the block. Locking a block disables write access to the block. Once a block is locked, it
cannot be unlocked. Read access to EEPROM blocks is unaffected by the lock/unlock status.
EEPROM REGISTER FORMAT
ADDRESS 1Fh
BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0
EEC LOCK X X X X BL1 BL0
EEC
—EEPROM Copy Flag. A 1 in this read-only bit indicates that a Copy Data Function command is in progress.
While this bit is high, writes to EEPROM addresses are ignored. A 0 value in this bit indicates that data can be
written to unlocked EEPROM.
LOCK
—EEPROM Lock Enable. When the lock bit is 0, the Lock Function command is ignored. Writing a 1 to this
bit enables the Lock Function command. After setting the lock bit the lock function command must be issued as the
next command, or else the lock bit is reset to 0. After the lock operation is completed, the lock bit is reset to 0. The
lock bit is a volatile R/W bit, initialized to 0 upon POR.