New low-voltage electrically tunable triode-MOSFET transconductor and its application to low-frequency Gm-C filtering

A new low-voltage electrically tunable transconductor is presented. Its transconductance can be settled by means of a ratio between a reference current and a reference voltage rendering the circuit independent of technological parameters, to a first order approach. This property allows, to some extent, reusing the transconductor in several CMOS processes. A kind of linear current division strategy turns also the transconductance inversely proportional to a product of two ratios between transistors' sizes that can be chosen so as to meet the desired Gm order of magnitude. This feature, together with a low-current biasing policy, is exploited in order to get a transconductance in the range of 1nS, as needed for very low-frequency filters. For a 2V supply and a 20pF load capacitor, an integrator characterization in a

• Type: Conference
• Year: 2005
• Where: SBCCI
• Authors: Carlos Dualibe, Pablo A. Petrashin, Luis E. Toledo, Walter J. Lancioni
• Keywords: Linear Current Division, Low-current Biasing Policy, SBCCI 2005, Tunable Transconductor