Two Takes on Making a Tl494 QSPICE Model

[mccunets]

For this week’s QSPICE schematic capture, we have two TL494 models built by our friends Edwin Scull and Alexander Bordodynov. They’ve taken slightly different approaches, the Forum thread for this is posted in the first comment, an interesting discussion. Please send any schematic capture submissions to me at tim.mccune@qorvo.com (Schematic Capture Post #025)
Parent.TL494.qsch (24.0 KB)

[mccunets]

My First PWM ic model (TL494ish)

Hi Bordodynov, Thank you for your reply. Apologies for the delay; I’m spending time with family this week and have limited PC access. That’s a very different approach – I like it! It looks like it models the IC more faithfully than mine, which was aiming for functional similarity. I particularly like the use of current sources to drive the output transistors. I’ll definitely experiment with this myself. Thanks, Ed

[bordodynov]

There is an extra R1 resistor in my model. I apologize. I have now reproduced the schema in the datasheet.

TL494.qsch (34.5 KB)
Parent.TL494.qsch (23.7 KB)

[mccunets]

Hi Alexander, many thanks, Tim