| Produttore elettronici | Il numero della parte | Scheda tecnica | Spiegazioni elettronici |
 National Semiconductor ... | LM4920 |  1Mb/17P | Ground-Referenced, Ultra Low Noise, Fixed Gain, 80mW Stereo Headphone Amplifier |
 National Semiconductor ... | LM49200 |  960Kb/26P | Stereo Class AB Audio Subsystem with a True Ground Headphone Amplifier |
 National Semiconductor ... | LM49200TL |  960Kb/26P | Stereo Class AB Audio Subsystem with a True Ground Headphone Amplifier |
 National Semiconductor ... | LM49200TLX |  960Kb/26P | Stereo Class AB Audio Subsystem with a True Ground Headphone Amplifier |