Mitel Networks SP8853B
The SP8853 is a low power single chip synthesiser intended for professional radio applications, containing all the elements (apart from the loop amplifier) required to build a PLL frequency synthesis loop The device is serially programmable by a three-wire data highway and contains three independent buffers to store one reference divider word and two local oscillator divider words. The preset operation of the charge pumps can be overwritten or the comparison frequencies switched to output ports under control of the divider word. The dual modulus ratio and so operating range is also programmable through the same word.