rkokholm
Newbie
I have designed my first fully differential amplifier, that is intended to be used as an integrator in a CTSDM. The design is a miller-compensated two-stage design, with ideal CMFB at this point. After running stability analysis, I wanted to set up a transient analysis to make sure the stability analysis was right. But unlike the transient analysis I have done on previous single-ended designs, I do not get something that makes sense on the outputs.
I'm sending a small step from a pulse source to a ideal balanced/unbalanced transformer, that makes the step differential around my common mode. The pulse source have the same AC magnitude as the voltage source used otherwise, to maintain the correct operation of the amplifier. But the output reacts very late to the step, and starts oscillating with peaks of up to +/- 3V, with a VDD of 1.6V and the common mode voltage at 0.8V.
This is the first time I'm designing something fully differential, and the first time I'm designing an integrator, and I feel like there is something I'm missing.
Any insights would be greatly appreciated.
I'm sending a small step from a pulse source to a ideal balanced/unbalanced transformer, that makes the step differential around my common mode. The pulse source have the same AC magnitude as the voltage source used otherwise, to maintain the correct operation of the amplifier. But the output reacts very late to the step, and starts oscillating with peaks of up to +/- 3V, with a VDD of 1.6V and the common mode voltage at 0.8V.
This is the first time I'm designing something fully differential, and the first time I'm designing an integrator, and I feel like there is something I'm missing.
Any insights would be greatly appreciated.
