Analog Devices announced a new IC. The LTCR3337 is a primary battery state of health (SOH) monitor with a built-in precision coulomb counter. It is designed to be placed in series with a primary battery with minimal associated series voltage drop. The patented infinite dynamic range coulomb counter tallies ALL accumulated battery discharge and stores it in an internal register accessible via an I2C interface. A discharge alarm threshold based on this state of charge (SOC) is programmable. When it is reached, an interrupt is generated at the IRQ pin. Coulomb counter accuracy is constant down to no load.
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| Typical Application. |
The LTC3337 also integrates additional SOH monitoring which measures and reports via I2C: battery voltage, battery impedance, and temperature.
To accommodate a wide range of primary battery inputs, the peak input current limit is pin selectable from 5 mA to 100 mA.
Coulombs can be calculated for either the BAT_IN or BAT_OUT pin, determined by the AVCC pin connection. A BAL pin is provided for applications utilizing a stack of two supercapacitors (optional) at the output.
The LTC3337 is offered in a 12-lead 2 mm × 2 mm LFCSP package.
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| Total Coulomb Counter Error (100 mA IPEAK Setting). |
Features
- Battery Input Voltage Range: 1.8 V to 5.5 V
- 100 nA Quiescent Current
- 8 Primary Battery Peak Input Current Limits: 5 mA/ 10 mA/ 15 mA/ 20 mA/ 25 mA/ 50 mA/ 75 mA/ 100 mA
- SOH Monitor for Primary Battery
- Integrated Coulomb Counter (Q)
- Additional Monitors for Battery Voltage (V), Battery Impedance (Z), and Temperature (T)
- Primary Battery Current (BAT_IN) or Load Current (BAT_OUT) is Counted
- Integrated ±10 mA Supercapacitor Balancer
- Programmable Coulomb Counter Prescaler for Wide Range of Battery Sizes
- Programmable Discharge Alarm Threshold with Interrupt Output
- I2C Interface
- Tiny 12-Lead 2 mm × 2 mm LFCSP
