Summary of ANALOG DEVICES INC. LTC3337 PRIMARY BATTERY STATE OF HEALTH MONITOR
Analog Devices LTC3337 is a primary battery state-of-health monitor that provides real-time measurements of discharge (coulombs), voltage, impedance, and temperature while inserting minimal series voltage drop. It integrates an infinite-range coulomb counter with I2C access, programmable discharge alarm with IRQ, selectable peak input current limits (5mA–100mA), and optional supercapacitor balancer. Available in a 2 mm × 2 mm LFCSP-12 with exposed pad, it operates from 8.0V to 5.5V with 100nA quiescent current and −40°C to +125°C rating.
Parts used in the LTC3337 Primary Battery State of Health Monitor:
- LTC3337 primary battery SOH monitor IC (Analog Devices)
- 2 mm × 2 mm LFCSP-12 package with exposed pad
- Battery (primary cell input, 5.5V to 8.0V range)
- Optional stack of two supercapacitors for BAL pin
- AVCC pin connection (for selecting BAT_IN or BAT_OUT measurement)
- I2C interface connection (SCL, SDA)
- IRQ pin connection for discharge alarm interrupt
- Configuration pins for peak input current selection (pin-selectable limits)
- PCB with thermal pad to mate the exposed pad
Analog Devices Inc. LTC3337 Primary Battery State of Health (SOH) Monitor provides accurate, real-time readings of battery cell discharge, voltage, impedance, and temperature. The LTC3337 is designed to be placed in series with a primary battery with minimal associated series voltage drop. This device integrates an infinite dynamic range coulomb counter that 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.
To accommodate a wide range of primary battery inputs, the peak input current limit of the LTC3337 is pin selectable from 5mA to 100mA.
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 Analog Devices Inc. LTC3337 Primary Battery State of Health Monitor is available in a 12-lead Lead Frame Chip Scale Package (LFCSP) with an exposed pad for improved thermal performance.
Features
- 8.0V to 5.5V battery input voltage range
- 100nA quiescent current
- 8 primary battery peak input current limits
- 5mA, 10mA, 15mA, 20mA, 25mA, 50mA, 75mA, 100mA
- SOH monitor for primary battery
- Integrated coulomb counter (Q)
- Additional monitors for battery voltage (V), battery impedance (Z), and temperature (T)
- Integrated ±10mA supercapacitor balancer
- Primary battery current (BAT_IN) or load current (BAT_OUT) is counted
- Programmable coulomb counter prescaler for a wide range of battery sizes
- Programmable discharge alarm threshold with interrupt output
- I2C interface
- -40°C to +125°C operating junction temperature range
- 2mm x 2mm LFCSP-12 package
Read more: ANALOG DEVICES INC. LTC3337 PRIMARY BATTERY STATE OF HEALTH MONITOR
- What does the LTC3337 monitor?
It monitors battery discharge (coulombs), voltage, impedance, and temperature. - How is accumulated discharge accessed?
The integrated coulomb counter stores accumulated discharge in an internal register accessible via I2C. - Can the LTC3337 generate an alarm when battery is low?
Yes, a programmable discharge alarm threshold based on state of charge triggers an interrupt on the IRQ pin. - How is peak input current limited?
The peak input current limit is pin selectable with options from 5mA to 100mA. - Does the coulomb counter work at no load?
Yes, coulomb counter accuracy is constant down to no load. - Can it handle supercapacitors?
Yes, a BAL pin supports applications using an optional stack of two supercapacitors and there is an integrated ±10mA supercapacitor balancer. - Which pin determines whether BAT_IN or BAT_OUT is measured?
Whether coulombs are calculated for BAT_IN or BAT_OUT is determined by the AVCC pin connection. - What is the supply and operating range?
It accepts battery input voltage from 8.0V to 5.5V and operates from −40°C to +125°C junction temperature. - What package is the LTC3337 available in?
It is available in a 12-lead LFCSP (2 mm × 2 mm) with an exposed pad for improved thermal performance.
