Advanced Energy VarioMatch Match Network VM 1000 Platform, Руководство пользователя

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The major practical problem of the L match network is the need for very large tuning
capacitors when matching low impedances - a typica l situation with plasma
chambers . The following table provides an idea of the load capacitor's capacity. The
load capacitor must provide for d i fferent load resistances:
Table 2-2.
Load capacitor capacity by load
R1oad
Load capacitor
0.5 Q 2335 pF
l.0Q 1640 pF
2.0 Q 1150 pF
3.0 Q 929 pF
4.0 Q 796 pF
5.0 Q 704 pF
6.0 Q 635 pF
7.0 Q 581 pF
8.0 Q 537 pF
At l oad resistances lower than 3 Q a capacity of l arger than 900 pF is required.
The V arioMatch match network uses a load coil to extend the capacitance range of the
load capaci t or withou t t he negative side effects described above. For more
information, see "Set Up the Match for Your Load" on page 5-16 .
Gamma Topology
2-6
In addition to the L match topo l ogy, AE produces match networks that use the Gamma
topology. Gamma topo l ogy matches allow loads of very l ow impedances to be
matched. This can be advantageous for ICP loads.
Some VarioMatch match network ICP units can be operated in two different
configurations, which allow two different load impedance ranges. Other VarioMatch
match networks use only Gamma topology. See Chapter 3, "Specifications" .
Product Overv i ew and T heory 57020080-00D