AD8313-Match


How to use this matching tool:

Enter the desired center frequency in the FC field at top right. Signal bandwidth is entered in the BW field to its right. The selected center frequency will highlight on the chart as a green circle along the blue input impedance line and the corresponding nominal impedance value will appear in ZRE and ZIM . A match is automatically calculated and appears on the chart in red (drawn over the specified bandwidth) with component values appearing in the box next to the schematic at lower right.

ZRE and ZIM can be manually entered, however, these values will be lost if FC or BW is changed. They can also be entered by clicking the mouse on the chart.

L and C component values are rounded to the nearest 5% value (R to 1%) and it's assumed they have a 5% manufacturing tolerance. Under these assumptions, the worst-case performance of the matching circuit can be estimated and is shown in yellow. By moving the mouse over the yellow square furthest from center, the worst-case return loss can be read from mouse documentation at upper left.

If no match is possible, the red and yellow markers will disappear. Another termination topology can be selected from the topology menu, or the load can be transformed by means of a stub, selected by entering the stub Z0 and length in the provided fields.

All matching topologies are narrowband and may require additional DC blocking caps to be compatible with the AD8313.