Figuring out how to use the H823 “Happy Birthday” music chip.
The H823 chip arrived in this CD4060 Dream Music Light DIY Kit and so far I have been unable to find a source for the H823 chip alone, or indeed anything approximating a datasheet.
Which of course is not unusual for these potted music chips! Figuring them out is half the fun;-)
Usage and Schematic
This is one of the simpler chips to control. At a minimum it just requires three connections:
- VCC: I’m using 5V, unsure yet what its upper and lower limits are.
- GND: gound
- OUT: signal out
The signal OUT can be used to directly drive the base of a low-side NPN control of a speaker or piezo buzzer.
There is one further connection on the chip board: after some experimentation, it appears this is a volume control. Attaching a potentiometer of around 5kΩ (through to ground) allows a full range volume control (from silent to maximum volume).
I laid out a simple circuit on protoboard (without the volume control circuit). I’m using a salvaged speaker which provides a reasonable clear output - certainly far better than the piezo buzzer often seen used with these chips in kits.