IN3LBQ on the Hühnerspiel (Amthorspitze) - photo by IN3OTD

Mitsubishi RD06HHF1/RD06HVF1 LDMOS model

Under construction...

The Mitsubishi RD06HHF1 is a medium power LDMOS (6 W) for the HF bands, which is often used as a driver for a couple of its bigger brother RD16HHF1 or also standalone for a QRP-level output power.
A very similar, if not identical, device is the RD06HVF1: this latter is specified in the datasheet up to 175 MHz (instead of 30 MHz only) but its electrical characteristics are otherwise identical to the RD06HHF1 and also the provided S-parameters are the identical, so the model shown here should be representative of both devices.

Model for Vdd=12.5 V and Idd= 500 mA

Typical S-parameters for this device can be found on the Mitsubishi web site, for a supply voltage of 12.5 V and a drain current of 500 mA.

Using the extraction method previously described, considering only the S-parameters from 50 MHz to 500 MHz, the following small-signal model parameters are determined:

Rg = 1.88 ohm
Rd = 1.60 ohm
Rs = 0.263 ohm
Lg = 3.01 nH
Ld = 2.73 nH
Ls = 0.835 nH
Cgs = 24.2 pF
Cds = 16.5 pF
Cgd = 1.35 pF
gm = 0.433 S
gds = 1.11 mS
So the equivalent small-signal circuit for this LDMOS at 500 mA drain current is the following: RD06HHF1 small-signal model - 500mA Smith chart with measured vs. model S-parameters: measured vs. modeled RD06HHF1 S-parameters - 500 mA S-parameters fitting details - fitted region is in white background: RD06HHF1 S11 500mA RD06HHF1 S12 500mA RD06HHF1 S21 500mA RD06HHF1 S22 500mA