LM4546 Datasheet | National Semiconductor

Description The LM4546 is an audio codec for PC systems which is fully PC98 pliant and performs the analog intensive functions of the AC97 Rev 2 architecture. Using 18-bit Sigma-Delta A/D’s and D/A’s, the LM4546 provides 90d B of Dynamic Range. The LM4546 was designed specifically to provide a high quality audio path and provide all analog functionality in a PC audio system. It features full duplex stereo A/D’s and D/A’s and an analog mixer with 2 stereo and 3 mono inputs, each of which has separate gain, attenuation and mute control. The LM4546 also provides National’s 3D Sound stereo enhancement. The LM4546 supports variable sample rate conversion as defined in the AC97 Rev2 specification. The sample rate for the A/D and D/A can be programmed separately to convert any rate between 4k Hz - 48k Hz with a resolution of 1Hz. The AC97 architecture separates the analog and digital functions of the PC audio system allowing both for system design flexibility and increased performance. Key Specifications n Analog Mixer Dynamic Range n D/A Dynamic Range n A/D Dynamic Range 97d B (typ) 89d B (typ) 90d B (typ) Features n AC’97 Rev 2 pliant n National’s 3D Sound circuitry n High quality Sample Rate Conversion (SRC) from 4k Hz to 48k Hz in 1Hz increments n Multiple Codec support n Advanced power management support n Digital 3V and 5V pliant Applications n Desktop PC Audio Systems n Portable PC Systems n Mobile PC Systems Block Diagram DS100985-1 FIGURE 1. LM4546 Block Diagram © 1999 National Semiconductor Corporation DS100985 .national. Absolute Maximum Ratings (Note 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage Storage Temperature Input Voltage ESD Susceptibility (Note 5) pins 27, 28 pin 3 ESD Susceptibility (Note 6) pin 3 Junction Temperature 6.0V - 40˚C to +150˚C - 0.3V to VDD +0.3V 2500V 1500V 750V 200V 100V 150˚C Soldering Information TQFP...