The LT ®1506 is a 500kHz monolithic buck mode switching regulator functionally identical to the LT1374 but optimized for lower input voltage applications. It will operate over a 4V to 15V input range compared with 5.5V to 25V for the LT1374. A 4.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. High switching frequency allows a considerable reduction in the size of external components. The topology is current mode for fast transient response and good loop stability. Both fixed output voltage and adjustable parts are available. A special high speed bipolar process and new design tech- niques achieve high efficiency at high switching frequency. Efficiency is maintained over a wide output current range by keeping quiescent supply current to 4mA and by utiliz- ing a supply boost capacitor to saturate the power switch. The LT1506 fits into standard 7-pin DD and fused lead SO-8 packages. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. Standard surface mount external parts are used, including the inductor and capacitors. There is the optional function of shutdown or synchronization.
The LT1506 is a constant‑frequency, 500 kHz buck‑mode switching regulator designed for low‑voltage applications. It operates from a 4 V‑15 V input range, provides up to 8.5 A switch current, and features an integrated shutdown pin that reduces quiescent current to 20 µA. Optional SYNC and BOOST pins allow external frequency control and higher drive voltage for the internal switch.
The device is supplied in a 7‑lead DD plastic package and includes detailed pin descriptions, typical performance graphs, and application circuits such as soft‑start, redundant operation, and dual‑output SEPIC configurations. Electrical characteristics, absolute maximum ratings, and typical performance data are provided for design reference.
| Switching Frequency | 500 kHz (constant) |
|---|---|
| Shutdown Supply Current | 20 µA |
The LT1506 operates at a constant 500 kHz switching frequency.
The shutdown supply current can be reduced to 20 µA.