It is very hard to find a standalone ADC that's not required interface with an mcu. Very most of modern ADCs produced by any brand must be configured via serial lines (i2c, spi etc).
If you want to a digital display, use generic adc types like "7106, 7107 or 7135...", give more detail about your requirements otherwise.
By my opinion it will be better using a cpu having ADC on it.