BT66/UM66 Melody Generator Musical Alarm IC

UM66T/BT66 is a melody integrated circuit. It is designed for use in bells, telephones, toys etc.

• It has an inbuilt tone and a beat generator. The tone generator is a programmed divider which produces certain frequencies.
• These frequencies are a factor of the oscillator frequency.
• The beat generator is also a programmed divider which contains 15 available beats. Four beats of these can be selected.
• There is an inbuilt oscillator circuit that serves as a time base for beat and tone generator.
• It has a 62 notes ROM to play music. A set of 4 bits controls the scale code while 2 bits control the rhythm code.
• When power is turned on, the melody generator is reset and melody begins from the first note.
• The speaker can be driven by an external NPN transistor connected to the output of UM66.