• This Project generates an rf carrier based on a pll
• with an MC12095 and MC12080 or MB 501
• locked on a 10.000 MHz reference

This project mayst be used as an standalone (fixed) LO. With these three prescalers, the following multiplication factors are possible :

NONE, N = 1	10	20	40	64	65	80	128	129
MC12095, N = 2	20	40	80	128	130	160	256	258
MC12095, N = 4	40	80	160	256	260	320	512	516

It is recommended to choose a ROS-oscillator from MiniCircuits, having a supply voltage of 5 V and a 5 V tuning voltage.

As we need a 400 MHz carrier, we have chosen the ROS-425-319+ from MiniCircuits. According to the datasheet, a tuning voltage of approx. 2.0 V should be necessary. We therfore choose the first prescaler to be N1 = 2 and using a MC12080 as a second prescaler with N2 = 20 mayst serve as a suiteable device. As we use a 10.0 MHz as a reference, this is also the phase comparator frequency. The Lowpass filter should therefore be calculated for a maximum frequency of 1 MHz. The used PLL circuit is a 74HCT9046. It has as typical charge pump curent of ± 1.06 mA (Rbias=40kΩ). The loop filter was calculated with this tool.

C17=680pF, R13=1k1, C20=4.7nF, R11=110, C14=2.2nF, IC1 not used.

C17=680pF, R13=2k2, C20=3.9nF, R11=1kΩ, C14=680pF, HMC363: dead bug technology.

• If there is no output of the prescaler, add a resistor of approx 2.2 kΩ from the output to gnd.

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