Any TopSpice Users Here? I have an OpAmp model out there that runs fine on PSpice, LTspice, HSpice, etc., but balks on TopSpice. The error...

Any TopSpice Users Here? I have an OpAmp model out there that runs fine on PSpice, LTspice, HSpice, etc., but balks on TopSpice. The error report, from the TopSpice output file is: GSw_Sw3 N_22 -VB VALUE {((TANH(9.485/0.1*(V(SHUTDOWN, + GND)-0.5))+1)/2)*(V(N_22, -VB)/1)} 0*ERROR*: mismatched parentheses in above expression check result= -1 0*ERROR*: loading VALUE be...

Lots of CMOS gates and such are tolerant of pin voltages above Vcc, typically rated for 7 volts max. Does anybody know what sort of input...

Lots of CMOS gates and such are tolerant of pin voltages above Vcc, typically rated for 7 volts max. Does anybody know what sort of input circuits are typically used? Does it behave like a zener? To ground? Some parts specify an allowed input curent in the pullup direction, some don't. I'm designing a really tiny board, and an opamp can potentially overdrive an analog mux, an FSA3157....

Hi I need to introduce and error in a signal, both quantization and sample/hold Sofar I have done it by placing an opamp based sample/hold...

Hi I need to introduce and error in a signal, both quantization and sample/hold Sofar I have done it by placing an opamp based sample/hold followed by a 8bit ADC (ADC8break) and a 8 bit DAC (DAC8break) But it doesn't feel right to use that much circuitry just to simulate an error in the system Anyone know if it can be done with ABM blocks? (sample and hold can be done with a zero order...

Hi all, months ago I bought this screaming fet opamp (THS463) to gin up an old photodiode circuit. Put it in today, and the step response doesn't...

Hi all, months ago I bought this screaming fet opamp (THS463) to gin up an old photodiode circuit. Put it in today, and the step response doesn't look right. Here's 1 k ohm of gain w/ 10 pF across it. https://www.dropbox.com/s/ncswyuokm9hktb5/step-10pF.BMP?dl=0 A lot of wiggles, but the amplitude isn't big enough. Here's the uncompensated step. https://www.dropbox.com/s/rilf9gvmlwldaj...

This is a continuation of the 50kHz VCO thread I started last week. I tried the stepped sine wave idea as suggested by James A, and...

This is a continuation of the 50kHz VCO thread I started last week. I tried the stepped sine wave idea as suggested by James A, and Phil H. The circuit clocks a MC14017 at 10x(F) to make a stepped sine wave at frequency (F). The ten outputs from the 4017 are sent through appropriate resistors and into the summing junction of an opamp. Here=92s a =91scope shot of the stepped output overlaid...

ADA4522 is an amazing amp. 55 volt supplies, low noise, 5 uV max offset, EMI hardened, pA bias current. But it has a hangup mode as a follower:...

ADA4522 is an amazing amp. 55 volt supplies, low noise, 5 uV max offset, EMI hardened, pA bias current. But it has a hangup mode as a follower: if the output goes to V+ the input back-to-back diodes keep both inputs above the legal common-mode range. Pity it's not RRIO. Similar amps from TI and Maxim seem to have the same issue. Here's one fix: https://www.dropbox.com/s/tdzs1ydi7quzbs7...

I'm wanting to simulate noise in a TIA. It will use a discrete jfet at the input, then opamps. Check me out on this, please: I assume...

I'm wanting to simulate noise in a TIA. It will use a discrete jfet at the input, then opamps. Check me out on this, please: I assume the jfet models have built-in gate equivalent noise voltages and currents, somewhere in the model string. Also assume the the LTC opamp models include noise params. Ditto Johnson noise in all resistors. The LT Spice help pdf file says that.....

This is a new-to-me lowpass topology, roughly 2nd order Bessel. The final RC stomps opamp high-frequency noise. Version 4 SHEET 1 880...

This is a new-to-me lowpass topology, roughly 2nd order Bessel. The final RC stomps opamp high-frequency noise. Version 4 SHEET 1 880 680 WIRE 96 32 48 32 WIRE 656 32 160 32 WIRE 368 112 336 112 WIRE 336 144 336 112 WIRE -160 160 -224 160 WIRE -96 160 -160 160 WIRE 48 160 48 32 WIRE 48 160 -16 160 WIRE 304 160 48 160 WIRE 448 176 368 176 WIRE 480 176 448 176 WIRE 512 176 480 176...