This post explains for the CMOS LSI Chip.
The Part Number is HT2811, HT-2811.
The function of this semiconductor is Ding Dong Door Bell.
The package is DIP 8 Pin Type
Manufacturer: Holtek
Preview images :
Description
The HT2811 is a CMOS LSI chip specially designed for the application of ding-dong door bell. It requir very low nombers of external component and provide low cost, high quality dual tone ding-dong sound. The IC is very suitable for door bell application.
The Ding Dong Door Bell IC is an example of an audio tone generator IC. It usually includes an oscillator and a sound generation circuit that produce the desired sound pattern. The IC may also have built-in drivers to directly connect to a small speaker or piezo transducer to produce the sound.
Pinouts:
Features
1. CMOS metal gate process
2. Low stand-by current : 1μA typically at VDD=3V
3. Good sound quality. (dual tone)
4. envelop adjustable by external RC
HT2811 PDF Datasheet
