Design of A Novel Highly EMI-Immune CMOS Miller OpAmp Considering Channel Length Modulation
- Resource Type
- Periodical
- Authors
- Boyapati, S.; Redoute, J.; Shojaei Baghini, M.
- Source
- IEEE Transactions on Circuits and Systems I: Regular Papers IEEE Trans. Circuits Syst. I Circuits and Systems I: Regular Papers, IEEE Transactions on. 64(10):2679-2690 Oct, 2017
- Subject
- Components, Circuits, Devices and Systems
Electromagnetic interference
Mathematical model
Integrated circuit modeling
Semiconductor device modeling
Immune system
Transistors
CMOS technology
CMOS
electromagnetic interference immunity
operational amplifiers with high EMI immunity
channel length modulation
mathematical modeling
output offset voltage
- Language
- ISSN
- 1549-8328
1558-0806
This paper presents a novel CMOS Miller operational amplifier (OpAmp) that has high immunity to electromagnetic interference (EMI). The proposed CMOS Miller OpAmp uses the replica concept with the source-buffered technique in order to achieve high EMI immunity across a wide range of frequencies (10 MHz to 1 GHz). The proposed amplifier is designed using the first-order quadratic mathematical model. The modeling includes the body effect and channel length modulation. The circuit has been fabricated using 0.18 $\mu \text{m}$ mixed-mode CMOS technology. Measurement results illustrate how the proposed Miller OpAmp reduces susceptibility to EMI even in the presence of high-amplitude interferences that are as high as 1 Vpp. Experimental results show that the maximum EMI-induced output offset voltage for the proposed Miller OpAmp is less than 10 mV over a wide range of frequencies (10 MHz to 1 GHz) when a 900 mVpp EMI signal is injected into the noninverting input. In contrast, the classic Miller OpAmp generates a maximum output offset voltage of 215 mV at 1 GHz under the same operating conditions. The measured results of the EMI-induced input offset corroborates the circuit simulations.