1
\$\begingroup\$

The question I need to solve is: how do the h parameters (hybrid) vary as a function of frequency?

In particular, I need to estimate the Y parameters (admitance parameters) for a 2N3904 transistor, but I only have the h parameters, as a function of the collector current, measured with a 1 kHz signal.

I need the Y parameters to model a circuit with this transistor, which operates at 10 Mhz. Is it possible to estimate the Y parameters @ 10 Mhz, from the h parameters @ 1 kHz?

I know that it is possible to convert from h parameters to Y parameters, but I don't know how the frequency variation affects it.

An alternative is to find a datasheet where the admittance parameters are specified for a range of frequencies, but I have searched without result.

\$\endgroup\$
3
  • \$\begingroup\$ Given Cob[coupling from col to base, and Ftau on how beta rolls off, and C_eb, what could you do? \$\endgroup\$ Apr 20, 2017 at 3:04
  • \$\begingroup\$ @analogsystemsrf You say calculate the admittances from the pi model? \$\endgroup\$ Apr 20, 2017 at 3:08
  • \$\begingroup\$ Certainly the two capacitors easily become part of a more detailed model. Ftau, describing beta rolloff, I've often used in napkin scribbles but not as part of formal model. \$\endgroup\$ Apr 20, 2017 at 3:10

1 Answer 1

0
\$\begingroup\$

Z, Y, H, S parameters are "measured" values at a specific bias and frequency.

You can convert H to Y but the bias and frequency is the same.

So 1Khz H can only be converted to 1Khz Y.

\$\endgroup\$
0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.