Title :
Effects of non-ideal characteristics of substrate BJT on bandgap reference circuits
Author :
Rui Bai ; Randall, Geiger L.
Author_Institution :
Dept. of Electr. & Comput. Eng., Iowa State Univ., Ames, IA, USA
Abstract :
The non-ideal characteristics of bipolar junction transistors (BJT) on the performance of band gap reference circuits is investigated. It is shown that the base spreading resistance (BSR) of a substrate BJT along with its temperature dependence has a significant negative impact on the performance of voltage references. It is shown that the temperature-dependent forward current gain (β) also adversely affects reference performance. In a typical application in a bulk CMOS process, the BSR causes an increase in the reference output of about 1% and the temperature dependent β introduces an inflection point shift of around 30 °C. After calibration the sensitivity changes by 25 ppm/°C.
Keywords :
CMOS integrated circuits; bipolar transistors; reference circuits; transistor circuits; BSR; bandgap reference circuits; base spreading resistance; bipolar junction transistors; bulk CMOS process; inflection point shift; nonideal characteristic effects; substrate BJT; temperature-dependent forward current gain; voltage reference performance; Calibration; Mathematical model; Photonic band gap; Resistance; Resistors; Temperature dependence; Temperature sensors; PNP BJT layouts; bandgap reference circuit; base spreading resistance; temperature dependent β;
Conference_Titel :
Circuits and Systems (MWSCAS), 2014 IEEE 57th International Midwest Symposium on
Conference_Location :
College Station, TX
Print_ISBN :
978-1-4799-4134-6
DOI :
10.1109/MWSCAS.2014.6908454
