Dual power supply detection circuit

Abstract

This disclosure relates to a dual power supply detection circuit, comprising: first and second input stage field effect transistors; an inverter stage; a feedback stage field effect transistor; first and second compensation circuits; wherein the inverter stage comprises a complimentary pair of transistors, the complementary pair of transistors comprising an NMOS transistor and a PMOS transistor configured and arranged such that a gate lengths of the PMOS and NMOS transistors are different. The disclosure also relates to an integrated circuit comprising a dual power supply detection circuit.

Description

technical field [0001] The invention relates to a double power supply detection circuit. The present disclosure also relates to an integrated circuit including a power supply detection circuit, and more particularly, to a logic integrated circuit. Background technique [0002] In power supply circuits for integrated circuits such as logic circuits, during power on or ramp up, the DC supply voltage (or Vcc) will rise and eventually settle at a certain DC value. As the DC supply ramps up, transistors in the power supply circuit experience sub-threshold voltages before a voltage node (such as a gate, source or drain) reaches a particular desired DC supply voltage (Vcc). Operation of transistors at sub-threshold voltages may cause unwanted voltage pulses at the output of the power supply. Such unwanted voltage pulses, also known as glitches, can cause unwanted behavior in integrated circuits to which the power supply circuit is connected. [0003] A glitch may be defined as a...

AI Technical Summary

Problems solved by technology

When the power supply is forcing current, the Vcc level may drop, causing the threshold for supply detection to shift, and may prevent the output from returning to Vcc, causing voltage oscillations, which can cause overcurrent

[0005] Also, with high to low voltage transitions and low to high voltage transitions and supply differences between Vcc and Vin in the two supply domains, the threshold voltages may not match

This mismatch can cause glitches

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