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300-mA linear battery charger with Power Path, integrated LDO and buck converter 2.5V default output

Inventory: 19,323
Custom reel may be available

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Packaging information

Package | Pins DSBGA (YFP) | 25
Operating temperature range (℃) I (-40 to 85)
Package qty | Carrier: 3,000 | LARGE T&R
Custom reel may be available
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Quality information

RoHS Yes
Lead finish / Ball material SNAGCU
MSL rating / Peak reflow Level-1-260C-UNLIM
Material content View
DPPM / MTBF / Fit rate View
Qualification summary View
Ongoing reliability monitoring View
Device marking View


  • Increases System Operation Time Between Charges
    • Configurable 300-mABuck Regulator
      (2.5-V Default)
    • 700 nA (typical) Iq with Buck Converter Enabled (No Load)
    • Configurable Load Switch or 100mA LDOOutput (Load Switchby Default)
    • Upto 300-mA Charge Current for Fast Charging
    • 0.5%Accurate Battery Voltage Regulation (Configurable from 3.6 V to 4.65 V in 10-mVSteps)
    • Configurable Termination Current Down to
      500 µA
    • Simple VoltageBased Battery Monitor
    • Watchdog TimerDisabled
  • Highly Integrated Solution with Small Footprint
    • 2.5 mm x 2.5 mm WCSP Package and 6 External Components for MinimalSolution
    • Push-ButtonWake-Upand Reset with Adjustable Timers
    • Power PathManagement for Powering the System and Charging theBattery
    • Power Path Management enables <50 nA Ship Mode Battery Quiescent Current for Longest ShelfLife
    • Battery Charger Operates from 3.4 V – 5.5VIN (5.5-V OVP / 20-V Tolerant)
    • Dedicated Pins for Input Current Limit, ChargeCurrent, Termination Current, and Status Output
  • I2C Communication Control
    • Charge Voltage andCurrent
    • Termination Threshold
    • Input CurrentLimit
    • VINDPM Threshold
    • TimerOptions
    • Load Switch Control
    • Controls for Interrupts forFaults and Status
    • System Output Voltage Adjustment
    • LDOOutput Voltage Adjustment

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The BQ25121A is a highly integratedbattery charge management IC that integrates the most common functions for wearable devices: Linearcharger, regulated output, load switch, manual reset with timer, and battery voltage monitor. Theintegrated buck converter is a high efficiency, low IQ switcher usingDCS-Control™ that extends light load efficiencydown to 10-µA load currents. The low quiescent current during operation and shutdown enablesmaximum battery life. The device supports charge currents from 5 mA to 300 mA. The input currentlimit, charge current, buck converter output voltage, LDO output voltage, and other parameters areprogrammable through the I2C interface.

The battery is charged using a standard Li-Ion charge profile with three phases:precharge, constant current and constant voltage. A voltage-based JEITA compatible battery packthermistor monitoring input (TS) is included that monitors battery temperature and automaticallychanges charge parameters to prevent the battery from charging outside of its safe temperaturerange. The charger is optimized for 5-V USB input, with 20-V tolerance to withstand linetransients. The buck converter is run from the input or battery. When in battery only mode, thedevice can run from a battery up to 4.65 V.

A configurable load switch allows system optimization by disconnecting infrequently useddevices. The manual reset with timer allows multiple different configuration options for wake arereset optimization. A simple voltage basedmonitor provides battery level information to the host in 2% increments from 60% to 100% of theprogrammed V(BATREG).

Qty Price
1-99 $3.23
100-249 $2.83
250-999 $1.99
1,000+ $1.60

Alternative carriers

Part number BQ25121AYFPT
Package qty | Carrier 250 | SMALL T&R
Inventory 2,750
Qty | Price (USD) 1ku | $1.84