U2733B-C

www.DataSheet4U.com U2733B-C Fractional-N Frequency Synthesizer for DAB Tuner Description The U2733B-C is a monolithically integrated fractional-N frequency synthesizer circuit fabricated in TEMIC’s advanced UHF5S technology. Designed for applications in DAB receivers, it controls a VCO to synthesize frequencies in the range of 70 to 500 MHz in a 16 kHz raster; four different reference divide factors can be selected. The lock status of the phase detector is indicated at a special output pin, six switching outputs can be addressed. An internal frequency doubler provides an output signal having twice the frequency of the reference oscillator. All functions of this IC are controlled by I2C bus. Features D Microprocessor controlled via I2C bus D 4 addresses selectable D Four reference divide factors selectable: 1024, 1120, 1152, 1536 D Effectively D Programmable 15-bit counter 1:2048 to 1:32767 effectively D Three state phase detector with programmable charge pump D Superior phase noise performance D Deactivation of tuning output programmable D 6 switching outputs (open collector) D Reference frequency doubler (open collector output) D Lock status indication (open collector) D Fully compatible to U2753B-C D SSO20 package Block Diagram FDO 10 Frequency doubler x2 Lock detector REF NREF 4 5 Reference counter Three State Phase Detector Fractional N control 2 Prog. charge pump VD 1 PD NFDO 9 3 PLCK 18 RF NRF 17 Prog. 13 Bit counter N/N=1 4 Bit latch 7 Bit latch 2 Bit latch 5 ...