LTC4098 USB-Compatible Switching Power Manager Application Circuit with Overvoltage Protection

SMF05C SOT363 ESD electrostatic protection tube 5V

Probe domestic switch needle KG-300K needle head diameter is 3.0mm normally open switch needle

description

The LTC4098/LTC4098-1 is a high efficiency USB PowerPathTM controller and full-featured Li-Ion/Li-Polymer battery charger. It seamlessly manages power distribution from a variety of power sources, including USB, wall adapters, automotive, FireWire or other high voltage DC/DC converters and Li-Ion/Li-Polymer batteries.

The LTC4098/LTC4098-1's internal switching regulator automatically limits its input current to maintain compatibility with the USB standard. For automotive and other high voltage applications, the LTC4098/LTC4098-1 is connected to a Linear Technology external switching regulator to provide a high efficiency, high voltage power path. Both USB and optional high-voltage inputs feature Bat-Track optimized charging to provide maximum power for the application and to mitigate thermal issues in high power density applications from 5V up to 38V.

An overvoltage protection circuit utilizes an N-channel FET and a resistor to protect the LTC4098/LTC4089-1 from high voltage damage on the USB/wall adapter input.

The LTC4098/LTC4098-1 are available in an ultra-thin (0.55mm height) 20-pin 3mm x 4mm QFN surface mount package.

Characteristics

• Switching regulator with Bat-TrackTM adaptive output control optimizes the use of limited power from the USB port to charge the battery and power the application
• Overvoltage protection prevents device damage
• Bat-Track External Step-Down Switching Regulator Control Maximizes Efficiency in Automotive, FireWire and Other High-Voltage Power Supplies
• 180mΩ internal ideal diode plus external ideal diode controller seamlessly provides low loss PowerPathTM (power path) when input power is limited or unusable
• Preset 4.2V charging voltage with 0.5% accuracy (4.1V for LTC4098-1)
• 4.1V Floating Voltage (LTC4098-1) Improves Battery Life and High Temperature Safety Margin
• Enables “on-the-fly” operation when the battery is exhausted
• Maximum load current of 700mA from the USB port
• Thermally limited 1.5A maximum charge current
• 20-pin 3mm x 4mm x 0.75mm QFN package

application

• media Player
• GPS
• PDA
• smart phone

LTC4098 Typical Application Circuit:

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