Lumped 2-Element Z-Y Matching Networks > Rload, Shunt C/L, Series C/L to Match Shunt R-C or R-L Device

Description

Given a shunt R-C equivalent input or output circuit of a device, this schematic computes component values of two networks to conjugately match the device to an output resistance. (The series R-C network can be converted to a series R-L network if the capacitance is set to a negative value, with formula given on the schematic.) Starting from a resistance, RL, the networks generate the complex conjugate impedance via shunt C - series L and shunt L - series C ladder networks.

Note For certain desired admittances, some of the calculated component values will be negative. These negative components must be replaced with positive ones. For example, negative inductors must be replaced by positive capacitors and negative capacitors must be replaced by positive inductors. The correct component values when such replacements are necessary are calculated on the data display.

The admittance of the equivalent circuit must be in one region of the Smith chart, which is shown on the schematic and in the figure shown here. If the admittance of the device's equivalent circuit is outside the hashed region, then use the next schematic to perform the transformation.

Main Schematic Settings

Device equivalent circuit ( Shunt R-C or Shunt R-L ) component values, load resistance, frequency of match

Data Display Outputs

• L and C component values of the two networks
• Generated impedances versus frequency, on a Smith chart
• Reflection coefficient (dB and on a Smith chart) presented to the external load resistor, versus frequency, for both networks. This is a perfect match at the matching frequency, but not at other frequencies.

Schematic Name

Ymatch1

Data Display Name

Ymatch1.dds