Soft-Start Protection Circuit for Hot-Plug Surge Current Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing soft-start schemes for server circuits face instability and component damage due to surge currents during hot plugging, with a risk of mis-operation in controlling the gate voltage of MOS transistors.
Innovation Solution
A soft-start protection circuit is designed with a protection chip, multiple switch tubes, capacitors, and resistors, which monitors voltage changes to ensure accurate turn-on and turn-off actions, reducing the impact of impulse currents.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the capacity of the capacitor is increased at the input end to stabilize the power supply, then the power supply stability is improved, but a large surge current occurs during hot plugging which causes instability of bus voltage and damage to components
Solution Approach 1:
The patent applies preliminary action by using the protection chip to detect bus voltage changes before the surge current can cause damage. The chip proactively controls the switch tube to limit current flow in advance, preventing the harmful effects of capacitor charging surge currents while still allowing the capacitor to stabilize the power supply.
Solution Approach 2:
The protection chip acts as an intermediary between the capacitor and the bus circuit. It monitors voltage changes and controls the switch tube to mediate the current flow, allowing the capacitor to perform its stabilizing function while preventing it from generating harmful surge currents that could damage components.
2Object-generated harmful factors
If RC delay and voltage stabilization are used to control the gate voltage climbing time of MOS transistor, then the impulse current is reduced, but there is a risk of mis-operation in controlling the gate voltage
Solution Approach 1:
The patent applies feedback by using the protection chip to continuously detect the bus voltage and provide feedback control for the switch tube gate voltage. This replaces the open-loop RC delay method with a closed-loop control system that adjusts the gate voltage based on actual bus voltage conditions, reducing impulse current while eliminating mis-operation risks.
Solution Approach 2:
The patent substitutes the passive RC delay circuit (electrical timing mechanism) with an active electronic control system using the protection chip. This replacement provides more reliable and accurate control of the gate voltage climbing time, reducing impulse current while preventing mis-operation through intelligent detection and control.
Data Source
AI summary
The present disclosure discloses a soft-start protection circuit, comprising: a protection chip, a first switch tube, a second switch tube, a third switch tube, a fourth switch tube, a first capacitor, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor and a seventh resistor. In the soft-start protection circuit of the present disclosure, the voltage of a voltage input end and the control end voltage of the first switch tube may be monitored; therefore, when there is a change in the two voltages, correct turn-on and turn-off actions may be performed in the soft-start protection circuit, increasing the accuracy of protection and at the same time reducing the turn-on speed of switch tubes to a certain extent, thus effectively reducing the impact of an impulse current on components and systems. Correspondingly, the present disclosure further discloses a circuit protection integrated chip.