DS2437S-3 Maxim Integrated Products, DS2437S-3 Datasheet - Page 3

• Manufacturer Part Number: DS2437S-3
• Description: IC MONITOR SMART BATTERY 16-SSOP
• Manufacturer: Maxim Integrated Products

Specifications of DS2437S-3

• Function: Battery Monitor
• Battery Type: Smart Batteries
• Voltage - Supply: 2.7 V ~ 10 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SSOP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

DS2437
Control function commands may be issued which instruct the DS2437 to perform a temperature
measurement or battery voltage A/D conversion. The result of these measurements will be placed in the
DS2437’s memory map, and may be read by issuing a memory function command which reads the
contents of the temperature and voltage registers. Additionally, the charging/discharging battery current is
measured without user intervention, and again, the last completed result is stored in DS2437 memory
space. The DS2437 uses these current measurements to update three current accumulators: one stores net
charge for gas gauge calculations, the second accumulates the total charging current over the life of the
battery, and the remaining accumulator tallies battery discharge current. The real time clock data, which
can be used in calculating battery self-discharge or time-related charge termination limits, also resides in
the DS2437 memory map and can be extracted with a control function command. The nonvolatile user
memory of the DS2437 consists of 40 bytes of EEPROM. These locations may be used to store any data
the user wishes and are written to using a memory function command. All data and commands are read
and written least significant bit first.
PARASITE POWER
The block diagram (Figure 1) shows the parasite-powered circuitry. This circuitry “steals” power
whenever the DQ pin is high. DQ will provide sufficient power as long as the specified timing and
voltage requirements are met (see the section titled “1-Wire Bus System”). The advantage of parasite
power is that the ROM may be read in absence of normal power, i.e., if the battery pack is completely
discharged.
DS2437 BLOCK DIAGRAM Figure 1
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