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For 2Cell Solar, Synchronous Switch-Mode Charger IC - BU1840AMUV

The BU1840AMUV device provides the best system to the product charged with 1cell Li-ion battery and 3cell Nickel-metal-hydride batteries using the 2cell, 3cell, and 4cell solar panel. It is possible to boost it according to the voltage of 2 cell solar panel with built-in the function to boost the low voltage input. Moreover, the solar battery maximum dissipation can be drawn out with built-in the peak power track function. It is possible to select the the switching frequency according to the terminal SEL. It is also possible to monitor the charging current by the I²C interface. Built in heat reckless driving protection (Thermal shutdown), decrease voltage protection, and input current protection for protection function.

* This product is a STANDARD grade product and not recommend for on-vehicle devices.
Part Number | BU1840AMUV-E2
Status | Active
Package | VQFN024V4040
Unit Quantity | 2500
Minimum Package Quantity | 2500
Packing Type | Taping
RoHS | Yes




Supply Voltage(Min.)[V]


Supply Voltage(Max.)[V]


ON Resistance [mΩ]


Operating Temperature (Min.)[°C]


Operating Temperature (Max.)[°C]



・ Synchronous Switch-Mode Charger for 2Cell Solar 400mA@Battery=3.7V,VIN=1V
・ MPPT control voltage range:0.7V~1.5V
・ Charging current completion voltage: 5.0V (hysteresis: 0.075V)
・ Built in MPPT
・ Switching frequency (160kHz,320kHz)
・ Charging current monitor by I²C
・ UVLO-detect Voltage:0.625V
・ UVLO-release Voltage:0.700V
・ Thermal Shutdown
・ 24 pin VQFN024V4040 (4.1mm×4.1mm)