The LT®3845 is a high voltage, synchronous, current mode controller used for medium to high power, high effi ciency supplies. It offers a wide 4V to 60V input range (7.5V minimum start-up voltage). An onboard regulator simplifi es the biasing requirements by providing IC power directly from VIN. Burst Mode® operation maintains high effi ciency at light loads by reducing IC quiescent current to 120μA. Light load effi ciency is also improved with the reverse inductor current inhibit function which supports discontinuous operation. Additional features include adjustable fi xed operating frequency that can be synchronized to an external clock for noise sensitive applications, gate drivers capable of driving large N-channel MOSFETs, a precision undervoltage lockout, 10μA shutdown current, short-circuit protection and a programmable soft-start. The LT3845 is available in a 16-lead thermally enhanced TSSOP package.
The LT3845 is a high‑voltage synchronous current‑mode step‑down controller with adjustable operating frequency, burst‑mode operation, and a 16‑lead TSSOP package. It supports input voltages from 4 V to 60 V and delivers output voltages up to 36 V with up to 5 A of load current.
This datasheet (handbook) includes features, absolute maximum ratings, pin configuration, electrical characteristics, typical performance curves, package dimensions, a typical application circuit, and a list of related parts.
| Input Voltage Range | 4 V to 60 V |
|---|---|
| Programmable Frequency Range | 100 kHz to 500 kHz |
| Shutdown Current | ≈ 9 pA |
| Current Limit Sense Voltage | 90 mV to 115 mV |
| Package | 16‑Lead Plastic TSSOP (FE) |
The LT3845 operates with an input voltage from 4 V up to 60 V.
The device allows a programmable switching frequency between 100 kHz and 500 kHz.
The LT3845 is supplied in a 16‑lead plastic TSSOP (FE) package.
The shutdown current is approximately 9 pA.