vco spice model

[Matt Flax]

Hello,

I am after a spice model for a voltage to frequency converter.

Does anyone have one handy ?

I have checked some of the manufacturer pages, but none seem to exist !
For example :
http://www.analog.com/en/prod/0,2877,AD537,00.html

thanks

 

[Jim Thompson]

Hello,

I am after a spice model for a voltage to frequency converter.

Does anyone have one handy ?

I have checked some of the manufacturer pages, but none seem to exist !
For example :
http://www.analog.com/en/prod/0,2877,AD537,00.html

thanks

In PSpice, other simulators may require editing notation style...

******************************************************************
..SUBCKT VCO_BEH VCONT OUT F PARAMS: FMAX=200Meg
+ VMAX=2V FMIN=100Meg VMIN=1V
..PARAM PI = 3.141593
G_G1 VC N_1 VALUE { 1+ TANH(80*V(VC, N_1)) }
G_G2 N_2 VC VALUE { 1+ TANH(80*V(N_2, VC)) }
R_R1 N_3 VC 10K
E_BUF1 N_3 0 VCONT 0 1
G_INTEG1 0 $$U_INTEG1 VALUE {V(OMEGA)}
C_INTEG1 $$U_INTEG1 0 {1/1.0}
R_INTEG1 $$U_INTEG1 0 1G
E_INTEG1 OUT 0 VALUE {V($$U_INTEG1)}
.IC V($$U_INTEG1) = 0v
R_R2 F 0 1K
V_V2 N_2 0 {VMIN-100m}
V_V1 N_1 0 {VMAX+100m}
R_R3 OUT 0 1K
R_R4 OMEGA 0 1K
E_E1 F 0 VALUE
+ {((V(VC,0)-VMAX)*(FMAX-FMIN)/(VMAX-VMIN)+FMAX)}
E_E2 OMEGA 0 VALUE { 2*PI*(V(F, 0)) }
..ENDS VCO_BEH
******************************************************************

...Jim Thompson

 

[Joerg]

Hello Jim,

Wasn't there a law that, at least for the state of Indiana:
..PARAM PI = 4?

Regards, Joerg

 

[Jim Thompson]

Hello Jim,

Wasn't there a law that, at least for the state of Indiana:
.PARAM PI = 4?

Regards, Joerg

I think it was indeed Indiana, but it was pi = 3, and only applied to
small circles ;-)

...Jim Thompson

 

[Robert]

I think it was indeed Indiana, but it was pi = 3, and only applied to
small circles ;-)

...Jim Thompson

Snopes says the modern hoax is about Alabama but does mention (at the
bottom) the bit about Indiana. They said it was passed in the Indiana House
but died in the Senate.

http://www.snopes.com/religion/pi.htm

Robert