# Murata #458PT-2002=P3: A Shielded Audio Transformer for Signal Coupling The Murata Electronics #458PT-2002=P3 is a compact audio transformer supplied on tape and reel. Published descriptions characterize it as a shielded winding-type balun with a ferrite core, intended for signal coupling and impedance matching at audio frequencies. Audio transformers remain useful because they provide galvanic isolation, common-mode rejection and impedance conversion without a power supply. Typical applications include balanced line inputs and outputs, isolation between equipment grounds to eliminate hum, telephone and intercom interfaces, and microphone or line-level coupling stages. The shielded construction helps reduce pickup of magnetic fields from nearby switching regulators or power transformers, which is a common source of hum and noise in compact audio products. Even so, careful placement away from strong magnetic sources and short, symmetric routing are good practice. The ChipApex catalog summary does not list turns ratio, impedances or frequency response, so engineers should design from the official Murata datasheet for this exact part and verify the footprint before releasing the PCB. Murata has issued discontinuation notices for several parts in this transformer range, so check current product change notifications, secure inventory for ongoing production and confirm the =P3 suffix when ordering. Detailed parameters, pricing and stock are listed on the [#458PT-2002=P3 Murata shielded SMD audio transformer](https://chipapex.com/product/458pt-2002p3/) page at ChipApex, an independent electronic components distributor in Shenzhen. You can also browse the full catalog at [ChipApex](https://chipapex.com/). ## Further reading Related ChipApex component notes and supplier profiles on other sites: - [KYOCERA AVX 006200067012800+ — notes](https://pad.c3voc.de/s/V6_LNMnA4) - [Murata #616DB-1191=P3 balun (end-of-life) notes](https://chipapexparts.mataroa.blog/blog/murata-616db-1191p3-a-1500-mhz-balun-nearing-end-of-life/) - [KYOCERA AVX 006200057032800+ — notes](https://md.warpzone.ms/s/k3HMOVZeQI) - [KYOCERA AVX 006200057052800+ — notes](https://pastefy.app/wqEvn0d9) - [Altera 10AT115N2F40E2SGES — notes](https://notes.netd.cs.tu-dresden.de/s/vWyuDrnJu) - [Altera 10AT115N4F40E3SGE2 — notes](https://pad.stuve.de/s/zZRTuU4-W) - [Altera 10AT115N4F40E4SGES — notes](https://hedgedoc.studentiunimi.it/s/j2WczDDOs) - [Altera 10AT115N4F40E3SGES — notes](https://notes.thecloud2.be/s/HnSONxtKl) - [AirBorn 00514-0433-0017 REV A — notes](https://md.nolog.cz/s/TPL7e51Bc) - [AirBorn 00514-0433-0018 REV A — notes](https://md.chaos.jetzt/s/SoFfqllj4)