T6668

The T6668 is a single chip CMOS LSI for voice recording and reproducing using the ADM(adaptive delta modulation) system. When a dynamic RAM is used as a voice data memory and an audio circuit including a microphone, speaker, amplifier, ete.is externally connected, a voice recording/ reproducing system can be composed.

The T6668 has the following features include:(1)a single chip LSI for voice recording / reproducing.;(2)D-RAM (Dynamic RAM) used as a voice data memory with the capacity up to 4pcs. of 64Kbit or 4pcs. of 256Kbit;(3)built-in counter to refresh D-RAMS;(4)easy connection with CPU. control by 9 kinds of commands;(5)capable of recording/ reproducing of max. 16 phrases;(6)selectable 4 kinds of bit rates (32k, 16k, 11k, 8kbps);(7)recording tone of each phrase is variable (MAX.128 sec. at 256KD-RAMX 4, bit rate 8kbps);(8)built in microphone amplifier for sound recording and band path filter for sound reproducing;(9)built in to bit D-A converter, voltage follower output;(10)built in oscillation circuit for ceramic resonator;(11)single 5V power supply:1mw power consumption by CMOS structure;(12)60 pin mini flat package.

The absolute maximum ratings of the T6668 are:(1)input voltage:-0.3 to Vdd+0.3;(2)output voltage:-0.3 to Vdd+0.3V;(3)supply voltage:-0.3 to +6.0V;(4)storage temperature range:-55 to +125°C.When the contents of the address counter reach the maximum address during the recording in the label index mode at the manual and CPU controls, the T6668 stops the recording automatically.In this case, the maximum address is stored as the the end address of a phrase at that time.Further, the address counter is preset at 00400H address and stops there.Therefore, in the recording / reproducing of the one phrase only, the stop switch (D5) becomes unnecessary.In other words, when a certain time has passed after starting the recording (when the recording is made to the last of RAM), the recording ends and also, the reproducing stops after the contents of RAM were spoken to the last.