Abstract
A small change to the standard current mirror op amp configuration is shown to improve performance, with few, if any, disadvantages. Adding a pair of fixed current sources allows reduced operating-point current in the output stage, while the resulting “leveraging” effect increases slew rate. For equal total power dissipation, the new configuration improves DC gain and gain-bandwidth (GBW) over conventional current-mirror and folded cascode op amps, as shown by hand analyses and SPICE simulations. Also, because of increased input stage transconductance, the new configuration reduces thermal and flicker noise.
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Fox, R.M., Seo, I., Yeo, H. et al. Leveraged Current Mirror Op Amp. Analog Integrated Circuits and Signal Processing 35, 25–31 (2003). https://doi.org/10.1023/A:1023417319188
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DOI: https://doi.org/10.1023/A:1023417319188