Bandgap refernce voltage generating circuit

Abstract

A bandgap reference voltage generating circuit, includes: at least two bipolar transistors; an operational amplifier; a first PMOS transistor; and a second PMOS transistor whose source is connected to the upper limit power supply voltage and which supplies the reference current to the bipolar transistors. Further, the bandgap reference voltage generating circuit includes a third PMOS transistor whose source is connected to the upper limit power supply voltage; a fourth PMOS transistor whose source is connected to the upper limit power supply voltage and gate is connected to a drain of the third PMOS transistor; a first NMOS transistor whose source is connected to the lower limit power supply voltage and drain is connected to a drain of the fourth PMOS transistor; and a second NMOS transistor whose drain is connected to the operational amplifier and gate is connected to the drain of the first NMOS transistor.

Description

[0001] This application claims priority from Korean Patent Application No. 10-2007-0137125 (filed on December 26, 2007), the entire contents of which are hereby incorporated by reference. technical field [0002] The present invention relates to a bandgap reference voltage generating circuit (bandgap reference voltage generating circuit), and more particularly, to a bandgap reference voltage generating circuit suitable for switching from a sleep mode to an operating mode. Achieve fast start-up and obtain stable bandgap output. Background technique [0003] In a semiconductor integrated circuit, the reliability of the entire system is improved by stably maintaining an internal biasing reference voltage. That is, even if the external power supply voltage (external power supply voltage), temperature or process changes, the devices in the integrated circuit can work without being affected by changes in the external power supply voltage, temperature or process. For this purpose,...

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Problems solved by technology

Then, when the sleep mode is switched to the active mode, when the mismatch between the input transistors of the operational amplifier exceeds the allowable amount or when the startup circuit does not operate normally, the output voltage of the bandgap circuit may not be set and cannot be put in high state

[0009] Therefore, the related reference voltage generating circuit has a problem in that, when the sleep mode is switched to the operating mode, the operational amplifier does not have a stable operating point due to the slow operation time (slow operation time) caused by the start-up circuit.

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