SparkFun Sunny Buddy MPPT Solar LiPo Charger

The SparkFun Sunny Buddy is an MPPT solar charger for single-cell LiPo batteries. It draws as much power as possible from a solar panel and is suitable for running an Arduino or ESP8266 on solar energy. The panel connects to the 5.5 mm / 2.1 mm jack, the battery to the JST connector and the load in parallel with the battery at LOAD.

Important: The output voltage comes directly from the LiPo. A 5 V Arduino therefore does not run on the Sunny Buddy without a step-up converter, as the voltage would otherwise be too low.

Recommended Accessories:

• Step-Up DC-DC Voltage Converter to 5V USB

Features:

• Maximum power point tracking (MPPT), point adjustable via the SET potentiometer
• Factory charge current 450 mA, approx. 550 mA with 1 Ω at R_SEN
• Do not charge the battery faster than its capacity allows: smallest LiPo 450 mAh
• Keep the load small, as it takes charging current away from the battery
• Solder pads for 3.5 mm screw terminals, terminals not fitted

Application Examples:

• Running Arduino or ESP8266 on solar energy
• Outdoor sensors with solar panel and battery
• Charging a LiPo cell with a solar panel

Documentation:

• Hookup guide (SparkFun)
• Schematic (PDF)
• LT3652 datasheet (PDF)

Technical Data:

• Chip: LT3652
• Manufacturer part no.: PRT-12885
• LiPo: 1 cell 3.7 V
• Solar input voltage: 6 V to 20 V
• Efficiency: over 80 %
• Version: V13
• Connections: SOLAR IN, BATT, LOAD, SET, GND, FAULT, CHG
• Dimensions: 47 × 47 × 13 mm
• Weight: 12 g

Scope of Delivery:

• 1× SparkFun Sunny Buddy MPPT solar LiPo charger