HT8658

The HT8658/HT8659 are single chip CMOS LSIs using an ADM coding technology. They are designed for applications on recording sounds.

The HT8658 and HT8659 have almost the same functions apart from the reset time. The reset time of the HT8658 has to be over 4 seconds but of the HT8659 over 2 seconds.

Blocks within each chip include a DRAM interface circuit, signal amplifier, 8 bit ADC and internal low pass filter. Encoded data are stored in external DRAMs and played back after the PLYB pin be triggered. Each HT8658 IC provides four kinds of sampling rate to be selected, namely 32K/22K/16K/11K bps (bits per second). A higher sampling rate results in sounds of better quality but sacrifices the recording time. With such a powerful built-in circuit, only few components are required for normal applications.

Each HT8658 can be offered in a dice form or 28 pin dual-in-line package.