The LM3420 series of controllers are monolithic integrated circuits designed for charging and end-of-charge control for lithium-ion rechargeable batteries. The LM3420 is available in an 8.4-V version for one through four cell charger applications.
●Included in a very small package is an (internally compensated) op amp, a bandgap reference, an NPN output transistor, and voltage setting resistors. The amplifiers inverting input is externally accessible for loop frequency compensation. The output is an open-emitter NPN transistor capable of driving up to 15 mA of output current into external circuitry.
●A trimmed precision bandgap reference utilizes temperature drift curvature correction for excellent voltage stability over the operating temperature range. The LM3420 series allows for precision end-of-charge voltage threshold for lithium-ion rechargeable batteries. The premium grade LM3420A is available with an initial voltage threshold tolerance of ±0.5%, while the standard grade LM3420 has an initial voltage threshold tolerance of ±1%.
●The LM3420 is available in a sub-miniature 5-lead surface mount package thus allowing very compact designs.
● Input Voltage Range: up to 20 V
● Voltage Options for Charging 1, 2, 3, or 4 Cells
● Output Current up to 15 mA
● Precision (0.5%) End-of-Charge Control
● LM3420 ±1%
● LM3420A ±0.5%
● Drive Capability for External Power Stage
● Temperature Drift Curvature Correction for
●Voltage Stability
● Low Quiescent Current, 85 µA (Typ.)
● Tiny SOT-23-5 package
