ds2761 Maxim Integrated Products, Inc., ds2761 Datasheet - Page 12

• Manufacturer Part Number: ds2761
• Description: Ds2761 High-precision Li+ Battery Monitor
• Manufacturer: Maxim Integrated Products, Inc.

DS2761
PROTECTION REGISTER
The protection register consists of flags that indicate protection circuit status and switches that give
conditional control over the charging and discharging paths. Bits OV, UV, COC, and DOC are set when
corresponding protection conditions occur and remain set until cleared by the host system. The default
values of the CE and DE bits of the protection register are stored in lockable EEPROM in the
corresponding bits in address 30h. A recall data command for EEPROM block 1 recalls the default values
into CE and DE. The format of the protection register is shown in Figure 9. The function of each bit is
described in detail in the following paragraphs.
Figure 9. PROTECTION REGISTER FORMAT
Address 00
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
OV
UV
COC
DOC
CE
DE
CC
DC
OV—Overvoltage Flag. When set to 1, this bit indicates the battery pack has experienced an overvoltage
condition. This bit must be reset by the host system.
UV—Undervoltage Flag. When set to 1, this bit indicates the battery pack has experienced an
undervoltage condition. This bit must be reset by the host system.
COC—Charge Overcurrent Flag. When set to 1, this bit indicates the battery pack has experienced a
charge-direction overcurrent condition. This bit must be reset by the host system.
DOC—Discharge Overcurrent Flag. When set to 1, this bit indicates the battery pack has experienced a
discharge-direction overcurrent condition. This bit must be reset by the host system.
CC — CC Pin Mirror. This read-only bit mirrors the state of the CC output pin.
DC — DC Pin Mirror. This read-only bit mirrors the state of the DC output pin.
CE—Charge Enable. Writing a 0 to this bit disables charging ( CC output high, external charge FET off)
regardless of cell or pack conditions. Writing a 1 to this bit enables charging, subject to override by the
presence of any protection conditions. The DS2761 automatically sets this bit to 1 when it transitions
from sleep mode to active mode.
DE—Discharge Enable. Writing a 0 to this bit disables discharging ( DC output high, external discharge
FET off) regardless of cell or pack conditions. Writing a 1 to this bit enables discharging, subject to
override by the presence of any protection conditions. The DS2761 automatically sets this bit to 1 when it
transitions from sleep mode to active mode.
STATUS REGISTER
The default values for the status register bits are stored in lockable EEPROM in the corresponding bits of
address 31h. A recall data command for EEPROM block 1 recalls the default values into the status
register bits. The format of the status register is shown in Figure 10. The function of each bit is described
in detail in the following paragraphs.
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