Abstract

NAGY, Agnes; POLANCO, Alicia  and  ALVAREZ, Manuel. Influence of emission coefficient N on bipolar transistor V_BE(T) model. uct [online]. 2005, vol.9, n.35, pp.163-166. ISSN 1316-4821.

The need to increase accuracy and stability in the design of temperature sensors and bandgap references has led to recent experimental studies on the variation with temperature of the emission coefficient n. The increase of n with the decrease of temperature, observed in these experiments, has been not explained yet. In this paper the physical cause of this increase is explained and the behaviour of n as a function of temperature is simulated. A new expression of base-emitter voltage VBE(T) including the emission coefficient is also obtained. The error in VBE(T), calculated from theoretical expressions, caused by neglecting the emission coefficient is greater than 2oC.

Keywords : Base-Emitter Voltage; Bipolar Transistor; Emission Coefficient; Emitter Capacitance; VBE(T) Model.