43 LCD Display for Radio HT16C21 Characteristics VDD = 3.3V ( Full Range : 2.4V ~ 5.5V ) VLCD = 3.3V ( VLCD ≤ VDD ) I2C-bus Interface Display Dot : 20 Segments 4 Commons ( Maximum : 20 Segments 4 Commons or 16 Segments 8 Commons ) 16-step Internal Voltage VLCD Adjustment Only a Few Components Required for the External Circuit Package Type : 28-pin SOP MCU Interface HT16C21 Application Areas Application Circuit Top Board Bottom Board