Typically, it is used with battery charger power path controllers to pre-regulate the output and optimize battery charger efficiency. Its wide operating input voltage of 7.5V to 30V makes the LT3653 ideal for a variety of input sources including unregulated 12V wall adapters, 24V industrial supplies and Firewire as well as automotive applications. Onboard input overvoltage lockout protects the device through input transients as high as 60V, such as those commonly found in automotive applications.
The LT3653's control pin, VC is available for external battery tracking, known as Bat-Track™ control. This function keeps the output voltage only 300mV above the Li-Ion battery voltage, which minimizes thermal issues while simultaneously optimizing charger efficiency.
Similarly, the LT3653 offers an adjustable output current limit which can be set between 400mA and 1.2A via an external resistor. The LT3653 does not allow reverse discharge from the battery to VIN, eliminating the need for a blocking FET. It also utilizes a 1.5MHz oscillator, internal compensation and an internal boost diode to minimize the overall solution footprint. Combined with a 2mm x 3mm DFN package, the LT3653 offers a very compact high voltage input regulator for battery charger applications.
|Summary of Features: LT3653
|Wide Input Range:
|•Operation from 7.5V to 30V
| •Overvoltage Lockout Protects Circuit through 60V
|Operates with LTC Bat-Track™ Li-Ion Battery Chargers
to Maximize Efficiency
|No Reverse Discharge Path from VOUT to VIN
|Programmable Output Current Limit
|Integrated BOOST Diode
|Small Application Size
Thermally Enhanced 2mm × 3mm DFN Packa