Designated LTC3337, Analog Devices Inc. introduces a state-of-health (SoH) monitor IC for (non-rechargeable) primary cells. The device contains a precision coulomb counter and is designed to be connected in series with a primary battery with minimal series voltage drop. The patented Coulomb counter with unlimited dynamic range records all accumulated battery discharges and stores them in an internal register. The register is accessed via an I2C interface. The SoH monitoring device operates with a quiescent current of only 100nA, which extends battery life.
The product has additional monitoring of the SoH variables of battery voltage, battery impedance and temperature, which are measured and reported via an I2C bus. To allow designers to work with as many different primary batteries as possible at the input, the peak input current limit can be set from 5 to 100mA via a connector pin. This allows the IC to give the battery a load profile that allows it to deliver maximum capacity regardless of the actual load. This is “battery friendly” and extends battery cell life.
It is ideal for primary cell applications that require only occasional power. These include applications in remote locations, electronic door locks, or glass break detectors. The component can also be used in conjunction with rechargeable battery cells.
