CN214256266U

CN214256266U - Low-cost signal latch circuit capable of being unlocked remotely

Info

Publication number: CN214256266U
Application number: CN202120314614.2U
Authority: CN
Inventors: 徐亮; 司修利; 袁宏亮; 林栋�; 印志江
Original assignee: Wotai Energy Co ltd
Current assignee: Wotai Energy Co ltd
Priority date: 2021-02-04
Filing date: 2021-02-04
Publication date: 2021-09-21
Anticipated expiration: 2031-02-04

Abstract

The utility model discloses a low-cost signal latch circuit capable of being unlocked remotely, which comprises a comparator, two protective voltage adjusting resistors, a latch resistor, a diode, a MCU controllable non-directional switch, a signal state detection circuit and a pull-up resistor; the comparator is connected with two voltage ends and a ground wire, a protection voltage adjusting resistor is arranged between one end of the comparator and the ground wire, a protection voltage adjusting resistor is arranged between the ground wire and the comparator, the comparator is connected to a signal state detection circuit and a pull-up resistor through two lines, one line is provided with a latch resistor, a diode and an MCU controllable non-directional switch, the signal state detection circuit is connected with the MCU, and the MCU is externally connected with a remote control, so that the trouble that the comparator is required to be manually unlocked on site after the comparator is mistakenly operated and enters a latch state due to signal interference or other factors can be effectively avoided, and the circuit cost is very low.

Description

Low-cost signal latch circuit capable of being unlocked remotely

Technical Field

The utility model belongs to the circuit field, concretely relates to but signal latch circuit of long-range unblock of low-cost.

Background

The comparator is a common component in electronic design, and has two ends with regulated functions, one end is set protection value and the other end is signal to be detected. The reaction and actuation time of the comparator is very short, typically in the us class, much less than the ms class of time required for software detection and reaction, and therefore comparators are often used for over-voltage and over-current protection in circuits.

Based on the principle, the comparator can be applied to the design of a battery short circuit, battery overcurrent or battery charging overvoltage protection circuit, but the comparator has a problem in use, and the level state of the output end of the comparator cannot be latched after being changed, so that the level of the output end of the comparator can be repeatedly changed when the causes of faults such as battery overvoltage, overcurrent and the like are not eliminated. For example, when the output end of the comparator is connected with the drive of the battery charging and discharging MOS and the comparator is used for the battery short-circuit protection, if the battery is short-circuited due to the breakage of the grid in the battery container, the current in the charging and discharging circuit of the battery will increase rapidly, when the current of the battery suddenly increases to reach the set overcurrent protection point, the comparator pulls down the driving signal of the driving MOS to disconnect the charge-discharge loop, when the charge-discharge circuit is disconnected, the current in the circuit becomes zero at a moment, at the moment, the comparator becomes an initial working state again, high level is output, the charge-discharge MOS is controlled to be opened, however, since the short-circuit condition in the charge/discharge circuit is not released, the current in the charge/discharge circuit still increases rapidly and still overflows, then the MOS … … is disconnected until the comparator is turned on and off continuously, and the protection function for preventing overvoltage and overcurrent cannot be really realized.

In order to solve the above problems, a common method is to add a signal latch chip behind the comparator for level latching of the comparator, so as to prevent the occurrence of the phenomenon that the level of the output end of the comparator changes frequently, but the signal latch chip is a trigger type chip, once latched, the whole system can be restarted manually to recover the work, which brings great trouble to the system application. Because the comparator compares the voltages at the two ends of the comparator, which are regulated by the function of the comparator, when the signal at the end to be detected is interfered by external signals, a false operation can be generated, and the false operation also wastes time and labor because the signal latch chip is required to restart the system on site due to the characteristic.

SUMMERY OF THE UTILITY MODEL

Therefore, in order to provide a controllable signal latch circuit that the cost is lower, the utility model provides a but signal latch circuit of long-range unblock of cost, concrete technical scheme is as follows:

a low-cost signal latch circuit capable of being unlocked remotely comprises a comparator, two protection voltage adjusting resistors, a latch resistor, a diode, an MCU (microprogrammed control unit) controllable non-directional switch, a signal state detection circuit and a pull-up resistor; the comparator is connected with two voltage ends and a ground wire, a protection voltage adjusting resistor is arranged between one end of the comparator and the ground wire, a protection voltage adjusting resistor is arranged between the ground wire and the comparator, the comparator is connected to the signal state detection circuit and the pull-up resistor through two lines, one line is provided with a latching resistor, a diode and an MCU controllable non-directional switch, the signal state detection circuit is connected with the MCU, and the MCU is externally connected with a remote control unit.

The combination of the diode MCU controllable non-directional switch can be replaced by an optical coupler.

The circuit has the advantages that remote communication can be carried out between the circuit and the MCU, the remote control switch is disconnected, remote unlocking is further realized, the trouble that the comparator needs to be manually unlocked on site after the comparator malfunctions and enters a latching state due to signal interference or other factors is effectively avoided, the circuit is low in cost, only one resistor, one diode and a switch which is nonpolarity and can be controlled by the MCU are needed, the cost is low, the effect is good, and the MCU can be used for realizing latching and unlocking of output signals of the comparator.

Drawings

Fig. 1 is a schematic diagram of the circuit structure of the present invention.

Detailed Description

In order to further understand the present invention, the following detailed description will be made with reference to the accompanying drawings and examples, which are only used for explaining the present invention and do not limit the scope of protection.

A low-cost signal latch circuit capable of being unlocked remotely is disclosed, and referring to fig. 1, the signal latch circuit comprises a comparator and two protective voltage regulating resistors R₁And R₂Latch resistor R₃Diode D₁MCU controllable non-directional switch J₁Signal state detection circuit and pull-up resistor R₄(ii) a The comparator is connected with two voltage ends and a ground wire, and a protective voltage regulating resistor R is arranged between one end of the comparator and the ground wire₂A protective voltage regulating resistor R is arranged between the ground wire and the comparator₁The comparator is connected to the signal state detection circuit and the pull-up resistor R through two lines₄One of the lines is provided with a latch resistor R_3、Diode D₁And MCU controllable non-directional switch J₁The signal state detection circuit is connected with the MCU, and the MCU is externally connected with a remote control.

At the initial stage of circuit start, the MCU controls J1 to be disconnected, and at the moment, the comparator circuit starts to work, because no current exists in the charge-discharge loop, the signal of the end to be detected is the reference voltage Vref which is less than the set voltage of the point A

The output end of the comparator is connected to the drive of the MOS or other high level signals through a pull-up resistor R4, and the output end of the comparator is externally shown as the output high level of the comparator. When the signal state detection circuit in fig. 1 detects a high level at the output end of the comparator, the MCU controls to turn on the J1, and at this time, because the potential at the point a is lower than the potential at the point B, the diode is not turned on, the circuit works normally, and there is no influence on other functions of the system. When overvoltage, overcurrent and other conditions occur, the triode connected with the output end of the comparator is switched on, the drive of the MOS or other high level signals are set to be low, at the moment, because the potential of the point B is low level, the diode D1 is switched on, and the resistance value of R3 needs to satisfy:

because the triode in the output end of the comparator is opened, R1 and R3 are connected in parallel, the state of the circuit is changed, the potential of the point C is smaller than Vref, the triode connected in the output end of the comparator is continuously opened, the output is represented as that the comparator continuously outputs low level, and the circuit enters a self-locking state.

After the circuit enters the self-locking state, if the comparator is required to be unlocked, the MCU controls the J1 to be disconnected, after the J1 is disconnected, the R3 is disconnected from the circuit, and the potential of the same-phase end of the comparator, namely the point A, is recovered as follows:

the circuit reverts to the initial state.

Therefore, the MCU can realize the latching and unlocking of the output signal of the comparator. And this circuit, the accessible carries out remote communication with MCU between, and remote control J1 disconnection, and then realizes remote unlocking, has effectively avoided because signal interference or other factors lead to the comparator malfunction and then need go the trouble of on-the-spot manual unblock after getting into the latch state, and this circuit cost is very low, only need increase a resistance, a diode, a nonpolarity can MCU controlled switch can, with low costs, effectual.

Claims

1. A low-cost signal latch circuit capable of being unlocked remotely is characterized in that: the device comprises a comparator, two protection voltage adjusting resistors, a latching resistor, a diode, an MCU (microprogrammed control unit) controllable non-directional switch, a signal state detection circuit and a pull-up resistor; the comparator is connected with two voltage ends and a ground wire, a protection voltage adjusting resistor is arranged between one end of the comparator and the ground wire, a protection voltage adjusting resistor is arranged between the ground wire and the comparator, the comparator is connected to the signal state detection circuit and the pull-up resistor through two lines, one line is provided with a latching resistor, a diode and an MCU controllable non-directional switch, the signal state detection circuit is connected with the MCU, and the MCU is externally connected with a remote control unit.