Datasheet

DS2762 High-Precision Li+ Battery Monitor With Alerts

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Temperature Interrupt High Threshold

Address 84

S 2

MSb LSb

Units: 1.0°C

Temperature Alarm Low Threshold

Address 85

S 2

MSb LSb

Units: 1.0°C

POWER SWITCH INPUT

The DS2762 provides a power control function that uses the discharge protection FET to gate battery power to the

system. The

PS pin, internally pulled to V

through a 1mA current source, is continuously monitored for a low-

impedance connection to V

. If the DS2762 is in sleep mode, the detection of a low on the PS pin causes the

device to transition into active mode, turning on the discharge FET. If the DS2762 is already in active mode, activity

PS has no effect other than the latching of its logic low level in the PS bit in the special feature register. The

reading of a 0 in the

PS bit should be immediately followed by writing a 1 to the PS bit to ensure that a subsequent

low forced on the

PS pin is latched into the PS bit.

MEMORY

The DS2762 has a 256-byte linear address space with registers for instrumentation, status, and control in the lower

32 bytes, with lockable EEPROM and SRAM memory occupying portions of the remaining address space. All

EEPROM memory is general purpose except addresses 30h, 31h, and 33h, which should be written with the

default values for the protection register, status register, and current offset register, respectively. All SRAM memory

is general purpose. When the MSB of any two-byte register is read, both the MSB and LSB are latched and held for

the duration of the read data command to prevent updates during the read and ensure synchronization between

the two register bytes. For consistent results, always read the MSB and the LSB of a two-byte register during the

same read data command sequence.

EEPROM memory is shadowed by RAM to eliminate programming delays between writes and to allow the data to

be verified by the host system before being copied to EEPROM. All reads and writes to/from EEPROM memory

actually access the shadow RAM. In unlocked EEPROM blocks, the write data command updates shadow RAM. In

locked EEPROM blocks, the write data command is ignored. The copy data command copies the contents of

shadow RAM to EEPROM in an unlocked block of EEPROM but has no effect on locked blocks. The recall-data

command copies the contents of a block of EEPROM to shadow RAM regardless of whether the block is locked or

not.