LM22670 is a 3A simple switch voltage regulator produced by National Semiconductor. It has a built-in low-resistance N-channel MOSFET, the output current can reach 3A, and has good line and load regulation characteristics. The switching frequency can be adjusted with an external resistor or synchronized to an external clock. It has internal thermal shutdown, current limiting and enable control input. The input voltage range is 4.5V to 42V.
The LM22670 series 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 go as low as 1.285 V, plus built‑in thermal shutdown, current limiting, and a precision enable pin for low‑power standby.
Designed for industrial control, telecom, embedded and automotive applications, the device uses a 500 kHz internal oscillator (adjustable 200 kHz‑1 MHz) and can be synchronized to an external clock. Available in TO‑263 THIN and PSOP‑8 packages with exposed pads for thermal dissipation, the LM22670 integrates all necessary control functions, reducing external component count.
| Input voltage range | 4.5 V to 42 V |
|---|---|
| Maximum output current | 3 A |
| Typical switching frequency | 500 kHz (adjustable 200 kHz‑1 MHz) |
| Efficiency | >90 % |
| Package options | TO‑263 THIN (120 mΩ) and PSOP‑8 (100 mΩ) |
| Thermal shutdown temperature | 150 °C |
| Standby quiescent current | 25 pA |
| Enable pin threshold voltage | 1.3 V – 1.9 V |
| Feedback reference accuracy | ±1.5 % |
| Operating temperature range | -40 °C to 125 °C |
The regulator accepts an input voltage from 4.5 V up to 42 V.
The internal oscillator runs at 500 kHz, and it can be adjusted between 200 kHz and 1 MHz.
It can drive loads of up to 3 A.
The standby quiescent current is typically 25 pA.