Key facts
- Model
- LM2598
- Industry
- Industrial
- Documents
- 2
- Languages
- EN
- Last added
- 2012-04-01
Start here
National Semiconductor LM2598 Datasheet
The LM2598 series provides a monolithic step‑down (buck) switching regulator capable of delivering 1 A with excellent line and load regulation. It is available in fixed output versions of 3.3 V, 5 V, 12 V and an adjustable version (1.2 V‑37 V), and operates at a 150 kHz fixed‑frequency internal oscillator.
The device is offered in a 7‑lead TO‑220 (through‑hole) package and a 7‑lead TO‑263 surface‑mount package, with typical applications including high‑efficiency buck conversion, pre‑regulation for linear regulators, and positive‑to‑negative conversion. Detailed electrical characteristics, absolute maximum ratings, and typical performance graphs are provided.
National Semiconductor LM2598 specifications
| Switching frequency | 150 kHz |
|---|---|
| Maximum supply voltage (V<sub>IN</sub>) | 45 V |
| Output current | 1 A |
| Fixed output versions | 3.3 V, 5 V, 12 V |
| Adjustable output range | 1.2 V – 37 V |
| Efficiency (12 V in, 1 A out) | 78 % |
| Thermal resistance (TO‑220, junction‑to‑ambient) | 50 °C/W |
All National Semiconductor LM2598 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What is the switching frequency of the LM2598?
The LM2598 operates at a fixed switching frequency of 150 kHz.
How much output current can the LM2598 supply?
The device is guaranteed to deliver up to 1 A of output current.
What is the maximum output current of the LM2598?
The LM2598 can deliver up to 1 A of output current.
From: National Semiconductor LM2598 Simple Switcher Power Converter Datasheet
What input voltage range does the LM2598 support?
It operates with an input voltage from 4.5 V up to 40 V.
From: National Semiconductor LM2598 Simple Switcher Power Converter Datasheet