The LM22673 is a 3A single-chip switching power supply chip that integrates a low-dropout linear regulator and a switching power supply controller. It has internal compensation voltage mode control, high stability, wide output voltage range and output current up to 3A.
The LM22673 series from National Semiconductor provides a monolithic step‑down (buck) regulator capable of delivering up to 3 A with high efficiency (>90%). It features a fixed 5 V output version and an adjustable version that can be set as low as 1.285 V. The device integrates a low‑ON‑resistance N‑channel MOSFET, internal voltage‑mode control, thermal shutdown, and current limiting, all selectable with a few external components.
The regulator is offered in TO‑263 THIN and PSOP‑8 exposed‑pad packages and operates over a wide input range of 4.5 V to 42 V. Design support is provided through National’s Webench® tools, and the part includes adjustable soft‑start and programmable current‑limit resistors for flexible application in industrial, automotive, telecom and embedded systems.
| Input voltage range | 4.5 V to 42 V |
|---|---|
| Maximum output current | 3 A |
| Switching frequency | 500 kHz (fixed) |
| Efficiency | >90 % |
| Operating temperature range | -40 °C to 125 °C |
| Adjustable soft‑start | Yes (external capacitor) |
| Adjustable current limit | Yes (external resistor on IADJ pin) |
The regulator operates at a fixed switching frequency of 500 kHz.
It accepts an input voltage from 4.5 V up to 42 V.