Bandgap Reference Circuit With Op Amp. An alternative bandgap voltage reference circuit uses an op amp as a summing amplifier with a forward biased diode and resistor. Bandgap voltage reference circuit built from a summing amplifier.
Bandgap voltage reference circuit 1 from the figure the emitter area of q1 is n times as large as the emitter area of q2 then is1 is2 n by op amp action with identical collector resistances the collector currents are also identical i e. A cm voltage reference with sub 1 v supply in bicmos technology was recently reported but the low voltage operationalamplifier op amp cannot be implementedindigital cmos. The capacitor across the op amp is for stability.
A current mirror circuit including first second and third transistors having first terminals connected to a voltage source and having gate terminals coupled by way of a gate control line to at least one output node of the op amp such that the first second and third transistors are.
This paper proposes a cmos bandgap reference bgr circuit which can successfully operate with sub 1 v supply in the conventional bgr circuit the output voltage v sub ref is the sum of the built in voltage of the diode v sub f and the thermal voltage v sub t of kt q multiplied by a constant. A cm voltage reference with sub 1 v supply in bicmos technology was recently reported but the low voltage operationalamplifier op amp cannot be implementedindigital cmos. Bandgap voltage reference circuit built from a summing amplifier. The handwaving explanation is you don t want the op amp to respond too fast or the system might start oscillating.
