Hi,

I am working on a simple project which requires ADC 0804 output. However the adc gives me 255 outputs, whereas I require just 8(3-bit) outputs. That is, I want the adc output mapped onto 3-bit output, where outputs from 0 to 32 are mapped unto single bit, 32 to 64 onto the next one, etc. These input would then be decoded by 3-8 decoder, lightning up 8 LEDs. ( lm3914 cannot be used)


Now, I want to ask if there is any IC which can help me with this function, or will I have implement 8 comparator circuits?

 

Just take the three most-significant bits and use those...

 

Yup, it really is that simple. Bit six changes state every 32 values, exactly what you describe. And bit 7 follows, and bit 8.

ak

 

ADC0804 → CD4028 → 8 LEDs
CD4028 - connecting D to GND, using 0~7 connecting to 8 LEDs and 8 resistors.