audio/videoZONE Products for the week of September 16, 2002

AKM Says . . .
New Stereo ADC from AKM

Asahi Kasei Microsystems Co., Ltd. (AKM) a leading supplier of audio ICs for professional and consumer markets today introduced the today introduced the AK5381, a 24-bit, 2-channel A/D converter. This high-performance 96 kHz, 24-bit A/D Converter is aimed at DVD-R, CD-R, electronic musical instruments and AV amplifiers.

The AK5381 utilizes AKM's proprietary dual-bit delta-sigma techniques. An integrated high-pass filter is used to eliminate DC offset. The chip requires no external components, as the inputs are single-ended. It operates off either a single 5-volt supply, or a split 5-volt/3-volt supply. The AK5381 can operate in both master and slave modes and has a defeatable high-pass filter that enables the conversion of signals down to DC levels. With 106dB of dynamic range and a 106dB signal-to-noise ratio, the AK5381 is ideally suited to consumer audio and professional music applications.

EN-Genius Network Says . . .

AKM has the uncanny knack of being able to very carefully position its products to give customers maximum bang for the buck: "What are you willing to pay?" Then, "Here's what you get for that." This is another performance notch up for the consumer market and is a nearly drop-in replacement (pin compatible) for the earlier AK5380, which was itself a performance replacement for the AK5353. So an OEM who has stayed with AKM has been able to notch up the specifications of his product without a major redesign.

The AK5381 pushes another 2 dB on S/(N+D) to 96 dB (at 5 V for 48 kHz) but the major change is in achieving 96 kHz performance with the digital voltage rail dramatically reduced: The AK5380 required a 4.5 V minimum; that is now reduced to 3.0 V in the AK5381. Also added is a master-mode/slave-mode selection for the audio interface, and the digital high-pass filter can now be bypassed to allow conversions down to dc.

The AK5381 can be operated between 4 kHz and 96 kHz sampling rates and continues to use single-ended inputs to the delta-sigma modulators with full-scale inputs of 3.0 V. The input impedances are 15 kilohms and matching of the two channels is within 0.1 dB. There is 110 dB isolation between the channels.

The decimation lowpass filter has a passband response of ±0.005 dB (to 21.5 kHz for 48 kHz sampling and 43.0 kHz for 96 kHz sampling.) The highpass filter has a -3 dB point at 1.0 Hz and 2.0 Hz respectively. Current consumptions were not yet known for the preliminary data sheet (available on request.)

This new part will continue to retain customers through the next generation of DVD (and the like) players and in A/V receivers. It will also help garner a lot of new users looking for a very nice price/performance balance.

The AK5381 is sampling now in TSSOP-16 and will be priced at $4.23 in 1000-piece lots.