Shanghai Huali Microelectronics Corporation

Shanghai Huali Integrated Circuit Corporation

Yifei Qian

Yu Jia

Xiangyang Li

Haifeng Wang

Zhili Wang

Xiaofeng Su

The present application discloses a multi-level voltage detector circuit. The voltage dividing circuit includes a first resistor string and a second circuit. The first resistor string is formed by n+1 voltage dividing resistors connected in series and outputs n divisional voltages. The second circuit provides n lower voltage dividing resistors. A kth lower voltage dividing resistor detects kth rise and fall detection points of a power supply voltage. When the kth rise detection point is detected, the second circuit provides a kth lower voltage dividing resistor and short-circuits the kth lower voltage dividing resistor. When the kth fall detection point is detected, the second circuit provides the kth lower voltage dividing resistor to a position between a second end of an nth voltage dividing resistor and the ground. As the value of k increases, the resistance of the kth lower voltage dividing resistor decreases.

Multilevel voltage detector circuit

This application discloses a system for turning off power consumption of an auxiliary startup circuit. An oscillator generates a switch control signal based on a reference current output by a circuit to be started up to generate a working clock of a switch control signal generation circuit after the circuit to be started up works normally. After fixed clock signal counting, the switch control signal generation circuit outputs a switch control signal to control power consumption of normally open current of the auxiliary startup circuit to be turned off. At the same time, the switch control signal generation circuit stops counting the clock. This application can assist the circuit to be started up having a 'degeneracy' bias point to power on normally, and can also turn off the power consumption of the auxiliary startup circuit after the circuit to be started up is powered on.

System for turning off power consumption of auxiliary startup circuit

The present application discloses a power-on-reset circuit, which optimizes a hysteresis circuit and a reset signal generation circuit, and introduces a seventh PMOS transistor as a switch transistor to achieve the differentiation of control voltages at a gate end of a first NMOS transistor during powering-on and off. A voltage rise detection point is determined by a partial voltage of a resistor during powering-on, while a voltage fall detection point is directly determined by a power supply voltage during powering-off. Such differentiation may achieve a significant separation between the voltage rise detection point and the voltage fall detection point, reducing the voltage fall detection point to near a threshold voltage of the first NMOS transistor, and meeting the demand for a lower voltage fall detection point, which is consistent with a practical application of the power-on-reset circuit in an MCU.

Power-on-reset circuit

The present application provides a distributed LDO regulator structure without an external capacitor. The structure includes one CORE module; and one or more POWER modules driven by one of the CORE modules. The CORE module comprises a mirror source voltage generating circuit and a built-in LDO regulator circuit. An output end of an operational amplifier and a gate of the sixth PMOS together serve as a control voltage end of the POWER module. A negative input end of the operational amplifier is connected to a drain of the fifth PMOS and a source of the sixth PMOS by means of a first resistor, wherein a connection end serves as an output end of the built-in LDO regulator circuit. POWER modules having the same output voltage are connected to each other in parallel.

Distributed LDO structure without external capacitor

The present invention discloses a power supply powering-on structure, which comprises an LDO module, a bandgap reference module, a voltage detection module, a bias module and a switch module; the working voltage of the LDO module, the voltage detection module and the bias module adopts external power supply voltage; the working voltage of the bandgap reference module adopts LDO output voltage; the switch module provides switching connection between the output of the bias module and the output of the bandgap reference module for a reference voltage input end and a bias current input end of the LDO module. The present invention can adopt internal power supply voltage to supply power to the bandgap reference module and can also solve the problem that the internal power supply voltage restricts the powering-on and starting of the bandgap reference module.

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Shanghai, China

Yifei Qian