LM3420-4.2

Features:

Voltage options for charging1, 2, 3 or 4 cells
Tiny SOT23-5 package
Precision (0.5%) end-of-charge control
Drive capability for external power stage
Low quiescent current,85µA(typ.)


Application

Lithium-Ion battery charging
Suitable for linear and switching regulator charger designs


Specifications

If Military/Aerospace specified devices are required,please contact the National Semiconductor Sales Office/Distributors for availability and specifications.
In put Voltage V(IN)                                            20V
Output Current                                                 20mA
Junction Temperature                                         50˚C
Storage  Temperature                       −65˚Cto+150˚C
Lead Temperature
    Vapor Phase(60seconds)                           +215˚C
    Infrared (15seconds)                                 +220˚C
Power Dissipation(T_A=25˚C)
   (Note2)                                                       300mW


Description

The LM3420-4.2 series of controllers are monolithic integrated Lithium-Ion rechargea blebatteries.The LM3420-4.2 is available applications(4.2V,8.2V/8.4V,12.6Vand16.8Vrespec-tively).

Included in a very small package is an (internally compen-sated)op amp,a bandgap reference,an NPN out puttransis   tor,and voltage setting resistors. The amplifier's inverting in put   is  externally accessible for   loop   frequency compensation. The output is an open-emitter NPN transistor capable of driving up to15 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.Available with an initial tol-eranceo f0.5% for the A grade version,and 1% for the stan-dard version,the LM3420 allows for precision end-of-charge contro lfor Lithium-Ionrechargeable batteries.

The LM3420-4.2 is available in a sub-miniature 5-lead SOT23-5 surface mount package thus allowing very compact designs.