Description
The S-8821 series is a CMOS step-up charge pump DC-DC converter with a voltage regulation function. The S-8821 series consists of an oscillation circuit, a controller, a reference voltage circuit, an error amplifier circuit, and an output switching transistor, and can regulate the output voltage by PFM control. Since small ceramic capacitors can be used for the pump capacitor, input capacitor, and output capacitor, the mounting area can be minimized.

Features
*Step-up PFM control CMOS charge pump
*Power supply voltage: 1.6 to 5.0 V
*Output voltage: 2.5 to 5.5 V, selectable in 0.1 V steps.
*Output voltage accuracy: ±2 % max.
*Built-in soft start circuit: 1.0 ms typ.
*Output current 25 mA (VIN=(VOUT(S) × 0.80) V)
*Oscillation frequency: 1.0 MHz typ.
*ON/OFF function: During standby: 1 μA max.
*Ultra-small package: SOT-23-6W
*Lead-free products

Applications
*Lithium ion battery driven applications
*Local power supply
*Power supply for white LED display backlights

S-882125AMH-M2ATFG, S-882130AMH-M2FTFG, S-882133AMH-M2ITFG

Trackback :: http://datasheetblog.com/trackback/2843

댓글을 달아 주세요 Comment

DESCRIPTION
The LTC®4057 is a constant-current/constant-voltage linear charger for single-cell lithium-ion batteries. Its ThinSOTTM package and low external component count make the LTC4057 especially well suited for portable applications. Furthermore, the LTC4057 is specifically designed to work within USB power specifications.
No external sense resistor is needed and no blocking diode is required due to the internal MOSFET architecture. Thermal feedback prevents overheating by regulating the charge current to limit the die temperature during high power operation or high ambient temperature conditions.
The charge voltage is preset at 4.2V and the charge current can be programmed externally with a single resistor.
When the input supply (wall adapter or USB supply) is removed, the LTC4057 automatically enters a low current state, dropping the battery drain current to less than 2mA. With power applied, the LTC4057 can be put into shutdown mode, reducing the supply current to 25mA.
For the standalone version (on-board charge termination) of the LTC4057, refer to the LTC4054.

FEATURES
*Programmable Charge Current up to 800mA
*No External MOSFET, Sense Resistor or Blocking Diode Required
*Constant-Current/Constant-Voltage Operation with Thermal Regulation Maximizes Charge Rate Without Risk of Overheating*
*Charges Single Cell Li-Ion Batteries Directly from USB Port
*Preset 4.2V Charge Voltage with ±1% Accuracy
*Current Monitor Pin for Charge Termination
*25mA Supply Current in Shutdown Mode
*Low Battery Charge Conditioning (Trickle Charging)
*Soft-Start Limits Inrush Current
*Available in a Low Profile (1mm) SOT-23 Package

APPLICATIONS
*Wireless PDAs
*Cellular Phones
*Portable Electronics

LTC4057ES5-4.2, LTC4057-4.2

Trackback :: http://datasheetblog.com/trackback/2483

댓글을 달아 주세요 Comment