SN761678B

www.ti.com FEATURES Single-Chip Mixer/Oscillator and Phase-Locked Loop (PLL) Synthesizer Three-Band Local Oscillator I2C Bus Protocol (Bidirectional Data Transmission) 30-V Tuning Voltage Output Four NPN-Type Band-Switch Drivers Programmable Reference Divider Ratio (512, 640, or 1024) External 4-Pin Intermediate Frequency (IF) Filter Between Mixer Output and IF Amplifier Input 5-V Power Supply 30-Pin Thin Shrink Small-Outline Package (TSSOP) APPLICATIONS TVs VCR/DVD Recorders Set-Top Boxes SN761678B TV TUNER IC SLES185 – JUNE 2006 DBT PACKAGE (TOP VIEW) VHI OSC C VHI OSC B OSC GND VLO OSC C VLO OSC B UHF OSC B1 UHF OSC C1 UHF OSC C2 UHF OSC B2 IF GND VCC IF OUT CP VTU XTAL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 30 UHF RF IN 29 VHF RF IN 28 BS4 27 RF GND 26 MIX OUT2 25 MIX OUT1 24 IF IN2 23 IF IN1 22 BS2 21 BS1 20 BS3 19 ADC 18 AS 17 SDA 16 SCL P0038-01 DESCRIPTION The SN761678B is a synthesized tuner IC designed for TV tuning systems. The circuit consists of a phase-locked loop (PLL) synthesizer, three-band local oscillator and mixer, 30-V output tuning amplifier, and four NPN band-switch drivers. The device is available in a small-outline package. A 15-bit programmable counter and reference divider are controlled by I2C bus protocol. Tuning step frequency is selectable by this reference divider ratio for a crystal oscillator. blk blk blk blk blk blk This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated cir...