LM4546

Supply Voltage ....................6.0V
Storage Temperature ....... −65°C to +150°C
Input Voltage ..........  −0.3V to VDD +0.3V
ESD Susceptibility (Note 5) ..........   2500V
pins 27, 28....................   1500V
pin 3.........................  750V
ESD Susceptibility (Note 6) ...........  200V
pin 3 ......................... 100V
Junction Temperature ..............150°C
Soldering Information
TQFP Package
Vapor Phase (60 sec.) ..............215°C
Infrared (15 sec.) .................220°C
See AN-450 ²Surface Mounting and their Effects on
Product Reliability² for other methods of
soldering surface mount devices.
_JA (typ)-VBH48A ............... 74°C/W

The LM4546 is an audio codec for PC systems which is fully PC98 compliant 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 90dB 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 4kHz - 48kHz 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.