The LTC4162 ICs are attractive as they provide the following benefits:

  • Wide Charging Input Voltage Range: 4.5V to 35V
  • High Efficiency Synchronous Operation>16-Bit Digital Telemetry System Monitors VBAT, IBAT, RBAT, TBAT, TDIE, VIN, IIN, VOUT
  • Charges multiple cell batteries
  • Input Undervoltage Charge Current Limit Loop>Input MPPT for Solar Panel Inputs
  • Input Current Limit Prioritizes System Load Output>Low Loss PowerPath™
  • Instant-On Operation with Discharged or Missing Battery
  • JEITA Temperature Controlled Charging

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I am currently sourcing parts from Mouser and building the sample circuit in KiCad