The LTC3122 is a synchronous boost DC/DC converter with true output disconnection and inrush current limitation. Available in a low-spec 12-lead (3mm x 4mm x 0.75mm) DFN package and 12-lead thermal enhanced MSOP package. The 2.5A current limit and the ability to program output voltages up to 15V make the LTC3122 ideal for a variety of demanding applications. Once started, the operation continues with inputs as low as 500mV, extending run time in many applications.
Pin Configuration
The LTC3122 has the feature of disconnecting the output at shutdown, greatly reducing the input power consumption and allowing the VOUT to discharge completely. Adjustable PWM switches from 100kHz to 3MHz optimize applications for maximum efficiency or minimum solution footprint. The oscillator can also be synchronized to an external clock for noise-sensitive applications.
Typical Application
The optional burst mode operation reduces the static current to 25 μA, ensuring high efficiency across the load range. Internal soft start limits inrush flow during startup. Other features include ＜1µa shutdown current and robust protection against short circuit, thermal overload, and output overvoltage conditions.
Block diagram
Features
● VIN range :1.8V to 5.5V, 500mV after starting
● Output voltage range :2.2V to 15V
● 800mA VIN = 5V, VOUT = 12V Output current
● The output is disconnected from the input
● Synchronous rectification: up to 95% efficiency
● Inrush current limit
● The maximum switching frequency is 3MHz It can be synchronized with the external clock
● Optional Burst Mode operation :25 μA IQ
● Output overvoltage protection
● Soft boot
● ＜1 μA IQ off
● 12-Lead, 3mm x 4mm x 0.75mm Enhanced DFN and MSOP packages
Applications
● Radio frequency power
● Piezoelectric actuator
● Small dc motor
● 12V analog rail from battery, 5V or spare capacitor
