The SN761677 is a single-chip synthesized tuner IC designed for TV/VCR tuning systems. The circuit consists of a PLL synthesizer, 3-band local oscillators and mixer, 30-V dc/dc converter for tuning the amplifier, four NPN emitter follower band drivers, four NPN open collector ports, and is available in a small package outline. The 15-bit programmable counter and reference divider are controlled by I2C bus control. Tuning step frequency is selectable by the reference divider ratio for a 4-MHz Xtal oscillator.