SP8855E

The SP8855E is one of a family of parallel load synthesisers containing all the elements apart from the loop amplifier to fabricate a PLL synthesis loop. Other devices in the series are the SP8852E which is a fully programmable device requiring two 16 bit words to set the RF and reference counters, and the SP8854E which has hard wired reference counter programming and requires a single bit word to program the RF divider. The SP8855E replaces the existing SP8855D.

The SP8855E is intended for applications where a fixed synthesiser frequency is required although it can also be used where frequency selection is set by switches. In general the device will be programmed by connecting the programming pins to either V_CC or ground. Additional hard wired inputs can be used to control the F_pd and F_ref outputs set the control direction of the loop and select the phase detector gain. Another input may be used to disable the phase detector output.

The SP8855E is available in both plastic (HP) and ceramic (HC) J-leaded 44-lead chip carrier. Ambient temperature ranges available are shown in the ordering information.