System aspects of current-mode circuits

Abstract

Since signals are normally represented as voltages, a voltage-to-current conversion is required at the input of most current-mode integrated circuits. A simple example of this is presented in Figure 5.1a, where a simple NMOS current-mirror is used as the input stage of an integrated circuit. Because the DC-voltage at the current-mirror input is sensitive to process and temperature variation, a DC-decoupling capacitor C is added in series with the off-chip resistor R.