Analog Circuit Design

Analog Integrated Circuit Design

Low voltage switched capacitor circuits

The analog design group of the E. y Electronica department at the Valladolid University has been working in collaboration with the Centro Nacional de Microelectrónica at Sevilla in the design and fabrication, via Europractice, of some circuit building blocks. These circuits has been designed for an AMS 0.35 µ m technology and their main feature is their low supply voltage. These circuits can operate with only 1 Volt.

Switched Operational Amplifier.

Features

Outputs Diferencial, rail to rail

Power Supply Voltage 1 V

Clock frequency 1 MHz

Power comsumption 90 µW

Outputs	Diferencial, rail to rail
Power Supply Voltage	1 V
Clock frequency	1 MHz
Power comsumption	90 µW

Layout of the opamp core and common mode feedback circuit (rigth)
Auxiliary circuits

Layout of the 2 phase clock generator
Layout of the polarisation circuit

ICECS2001 conference (Malta, Sept. 2001)

Paper
Slides

SC Filter.

Features:


Type	Biquad, band-pass
Order	2
Clock frequency	1 MHz
Resonance frequency	58 KHz (RDS subcarrier)
Q	20

Complete filter Layout

We can see 3 opamps (top), the capacitor bank (bottom) and, in the periphery, the switches, clock, polarisation circuits and buses.