SP5748

SP5748 2.4GHz Very Low Phase Noise PLL Advance Information DS4875 - 1.3 November 1998 The SP5748 is a single chip frequency synthesiser designed for tuning systems up to 2.4 GHz and is optimized for low phase noise with comparison frequencies up to 4 MHz. It is designed to be downwards software compatible with the SP5658. The RF programmable divider contains a front end dual modulus 16/17 functioning over the full operating range and allows for coarse tuning in the upconverter application and fine tuning in the downconverter. Comparison frequencies are obtained either from a crystal controlled on-chip oscillator or from an external source. a buffered reference frequency output is also available to drive a second SP5748. The device also contains 2 switching ports. CHARGE PUMP CRYSTAL CAP CRYSTAL ENABLE DATA CLOCK PORT P1/OC 14 SPOT REF. DRIVE VEE RF INPUT RF INPUT VCC REF PORT P0/OP MP14 Figure1 Pin connections - top view APPLICATIONS FEATURES q Complete 2.4 GHz single chip system (for faster device refer to to SP5768) q Optimised for low phase noise, with comparison frequencies up to 4 MHz q No RF prescaler q Selectable reference division ratio q Reference frequency output q Selectable charge pump current q Integrated loop amplifier q Two switching ports q Low power replacement for SP5658 and 5668 q Downwards software compatible with SP5658 q ESD protection, (Normal ESD handling procedures should be observed) q TV, VCR and Cable tuning systems q Communications systems ...