CN202121314U

CN202121314U - A 48 V circuit hot swap protective device

Info

Publication number: CN202121314U
Application number: CN2011202360588U
Authority: CN
Inventors: 肖兰
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-07-06
Filing date: 2011-07-06
Publication date: 2012-01-18
Anticipated expiration: 2021-07-06

Abstract

A 48 V circuit hot swap protective device includes a surge current control module, a current-limiting module and a thermally cutoff module. The surge current control module, the current-limiting module and the thermally cutoff module are connected in consequence. In the 48 V circuit hot swap protective device, the surge current control module can prevent surge phenomenon generated in a swap process and smooth the current; the current-limiting module can prevent an over-current case in the swap process, and limit the largest current; and the thermally cutoff module turns off the circuit once the instant temperature is detected to reach a threshold value, and the heat protection is formed.

Description

48V circuit hot swap protective device

Technical field

The utility model relates to a kind of circuit protection device, especially 48V circuit hot swap protective device.

Background technology

When circuit board inserted charged backboard, the shunt capacitance of power module or Switching Power Supply input can suck very big surge current on the circuit board when they discharge.Uncontrolled surge current will cause transient fault on system power supply, the device on the damaged line plate lacks a kind of line protection device of hot connecting and disconnecting easily in a lot of electric equipments.

Summary of the invention

In order to overcome the shortcoming that traditional 48V circuit arrangement lacks a kind of hot connecting and disconnecting line protection device.The utility model provides a kind of 48V circuit hot swap protective device, thus make allow to be adopted thinner circuit board wiring by protective circuit, can use and allow to adopt general small-sized component on cheap miniature connector, the power channel.

The utility model solves the technical scheme that its technical problem adopted: 48V circuit hot swap protective device; Comprise surge current control module, current limliting module, heat shutoff module; It is characterized in that surge current control module, current limliting module, heat are turn-offed module and connected successively.48V circuit hot swap protective device prevents the surge phenomenon that the plug process produces through the surge current control module; Smoothing current, the current limliting module prevents the overcurrent condition in the hot plug process, the restriction maximum current; Heat is turn-offed module detection instantaneous temperature and is reached then breaking circuit of fault value, forms the heat protection.

The beneficial effect of the utility model is in system, behind the interpolation circuit hot swap protective device, can reduce the requirement to main power source, thereby remedy the raising of system cost.

Description of drawings

Fig. 1 is the theory diagram of the utility model; Fig. 2 is the electric structure chart of the utility model.

Embodiment

In Fig. 1,48V circuit hot swap protective device comprises surge current control module 1, current limliting module 2, heat shutoff module 3, and surge current control module 1, current limliting module 2, heat are turn-offed module 3 and connected successively.48V circuit hot swap protective device prevents the surge phenomenon that the plug process produces through surge current control module 1; Smoothing current; Current limliting module 2 prevents the overcurrent condition in the hot plug process; Restriction maximum current, heat turn-off module 3 detection instantaneous temperatures and reach then breaking circuit of fault value, form the heat protection.

In Fig. 2, surge current control module 1 adopts MAX5920, can be installed in backboard or movably on the circuit-board card, through an outside N channel mosfet adjustment pipe powering load of on power channel, placing.When circuit board links with backboard first; Between GATE pin and VEE, to have internal dynamic clamped with moving MAX5920 on the grid voltage to for the drain electrode of Q1 and the electric capacity between the grid; It is low can during heat is inserted, keeping the gate source voltage of Q1, prevents that Q1 from giving load with uncontrolled current delivery.In great majority are used, can save outside grid source electric capacity.In the integrated circuit board insertion process, resistance R 3 is used for limiting the electric current that flows into clamped circuit.MAX5920 inner integrated current-limiting function and circuit breaker, so as load current excessive with short-circuit conditions under protective circuit.Voltage through detecting outside inspection leakage resistance between VEE and the SENSE comes monitor load current.If the voltage between V EE and the SENSE reaches current limliting threshold voltage (V CL), MAX5920 can draw electric current to realize the load current adjusting from the GATE end.This has just reduced the gate source voltage of outside MOSFET, thereby reduces load current, and MAX5920 comprises an internal die temperature monitor, and when die temperature reached heat shutoff threshold values T OT, the MOSFET grid was dragged down, disconnecting external MOSFET.If good passage of heat is arranged between MOSFET and the MAX5920, chip can be outside MOSFET the heat protection is provided.Because most of power consumption in drain electrode, is placed MAX5920 near the drain electrode of outside MOSFET, can obtain best heat protection effect.

Claims

1. 48V circuit hot swap protective device; Comprise surge current control module (1), current limliting module (2), heat shutoff module (3); It is characterized in that surge current control module (1), current limliting module (2), heat are turn-offed module (3) and connected successively.