一级代理BL4054 SOT23-5 上海贝岭，批号：全新，库存：25000只（长期现货）。原装***，现货热销。。。
BL4054FEATURES
Programmable Charge Current Up to 800mA
No MOSFET, Sense Resistor or Blocking
Diode Required
Preset 4.2V Charge Voltage with &plu***n;1%
Ac c uracy
Charge Current Monitor Output for Gas
Gauging
Thermal Regulation Maximizes Charge Rate
Without Risk of Overheating
Charges Single Cell Li-Ion Batteries Directly
from USB Port
Over-Voltage Protect
Automatic Recharge
Charge Status Output Pin
C/10 Charge Termination
25mA Supply Current in Shutdown
2.9V Trickle Charge Threshold
Soft-Start Limits Inrush Current
***ailable in 5-Lead SOT-23 Package
DESCRIPTION
The BL4054/BL4054B is a c o mplete c***tant
current / c***tant voltage linear charger for single
cell Lithium-Ion batteries. No external sense resistor is needed, and no blocking diode is
required due to the internal MOSFET architecture.
Thermal feedback regulates the charge current to
limit the die temperature during high power
operation or high ambient temperature. The
charge voltage is fixed at 4.2V, and the charge
current can be programmed externally with a
single resistor. The BL4054/BL4054B automatical
-ly terminates the charge cycle when the charge
current drops to 1/10 the programmed value after
the final float voltage is reached.
When the input supply (wall adapter or USB
supply) is removed, the BL4054/BL4054B
automatically enters a low current state, dropping
the battery drain current to less than 2mA. The
BL4054/BL4054B can be put into shutdown mode,
reducing the supply current to 25mA. Other
features include charge current monitor,
under-voltage lockout, automatic recharge and a
status pin to indicate charge termination and the
presence of an input voltage.
The only difference bet w een BL4054 and
BL4054B is that at power on, BL4054 will check
the battery voltage first, it will not start charging
unless the battery voltage is below the
auto-rechrage threshold. BL4054B does not
perform this check. So BL4054B can guarantee
the high battery capacity at all time, while BL4054
can prevent the battery from being repeatedly
charged in some specific applicati***.