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Hard startup / shutdown system

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Publication number
CN103869722A
CN103869722A CN 201410139119 CN201410139119A CN103869722A CN 103869722 A CN103869722 A CN 103869722A CN 201410139119 CN201410139119 CN 201410139119 CN 201410139119 A CN201410139119 A CN 201410139119A CN 103869722 A CN103869722 A CN 103869722A
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shutdown
startup
circuit
system
hard
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CN 201410139119
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Chinese (zh)
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CN103869722B (en )
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关晓丽
关贤光
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广东宝莱特医用科技股份有限公司
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Abstract

The invention discloses a hard startup / shutdown system. The hard startup / shutdown system comprises a power source, an over-current protection circuit, a startup / shutdown key, a hardware startup circuit, a software shutdown circuit, a hardware compulsory shutdown circuit, a hardware compulsory shutdown time regulating circuit and a key detection circuit. Compared with the prior art, the hard startup / shutdown system has the advantages that hardware startup time is controllable, shutdown states can be detected, the standby state hardly consumes power, and the hard startup / shutdown system is simple, safe and reliable.

Description

一种硬开关机系统 A hard switch system

技术领域 FIELD

[0001] 本发明涉及医疗设备领域,确切地说是指一种硬开关机系统。 [0001] The present invention relates to the field of medical devices and, more particularly refers to a hard switching system.

背景技术 Background technique

[0002]目前,在医疗设备的开关机电路中,设计方式一种是硬件开关机,另一种是软件开关机方式,第三种是硬件开关机+软件关机方式。 [0002] Currently, the switching circuitry in a medical device, a way to design a hardware switch, the other switch is the software embodiment, the third switch is a hardware + software shutdown mode. 第一种是通过电源按钮的按下与断开机械的控制系统电源,控制方式简单且待机电流可达零功耗。 The first is a simple control system by pressing the power button and disconnection of the power machine, control and zero-power standby current up. 第二种通过微控制器来控制系统电源的开启与关闭,关闭系统电源后可进入待机状态,仍然会消耗HiA级别或几百uA级别电流,更严重的问题是微控制器死机或瘫痪的情况下,只有断开电池以及外部电源的情况下才能恢复,为产品维护带来极大不便。 The second is controlled by a microcontroller on and off the system power, after power down the system may enter the standby state, still consumes hundreds uA HiA level or current level, the situation is more serious problem microcontroller crash or paralyzed under the case only disconnect the battery and external power supply can be restored for product maintenance caused great inconvenience. 第三种是前两种的结合,这种电路也经过不少的改进,其中有把硬件开关机机械的控制方式改为电路控制,譬如利用触发器良好的取反性来达到替代机械控制系统开启与关闭的目的,稳定性更强了点,但是触发器得时刻耗电。 The third is a combination of the first two, this circuit has also been a lot of improvement, which the hardware switch control circuit to control the machine, such as a flip-flop using inverted good resistance instead of mechanical control system to achieve opening and closing purposes, more stable point, but have a time trigger power.

[0003] 随着现代医疗设备技术的提升,也对开关机电路提出了更高的要求:1、一些用户配置数据以及正在处理的关键数据得能够及时加以保存后再进行关机动作,此时机械式立即关机断电的方式不可取;2、在碰到软关机失灵的情况下,得有硬件强制关机,此时MCU控制系统电源的方式不可取;3、做到低功耗,电池使用更持久,此时mA级别或几百uA级别电流的静耗电得加以改进。 [0003] With the improvement of modern medical device technology, the circuit can shut off a higher requirements: 1, a number of user configuration data and key data are processed to obtain timely be saved after shutdown operation, this time mechanical immediate shutdown of formula desirable way off; 2, encountered in the case of soft shutdown failure, the hardware must have forced shutdown, then MCU control system power supply undesirable manner; 3, to achieve low power consumption, battery life and more durable, this time the level of static or hundreds mA uA current consumption levels have to be improved.

发明内容 SUMMARY

[0004] 针对上述缺陷,本发明解决的技术问题在于提供一种硬开关机系统,硬件关机时间可控,关机状态可检测,待机几乎零功耗的简单,安全可靠。 [0004] For the above disadvantages, the present invention is to solve the technical problem is to provide a hard switching system, hardware controlled shutdown time, the shutdown state can be detected, almost zero standby power simple, safe and reliable.

[0005] 为了解决以上的技术问题,本发明提供的硬开关机系统,包括电源以及过流保护电路、开关机按键、硬件开机电路、软件关机电路、硬件强制关机电路、硬件强制关机时间调节电路和按键检测电路,其中: [0005] In order to solve the above technical problems, hard switching system provided by the present invention, comprising a power supply and the overcurrent protection circuit, switch button, power circuit hardware, software shutdown circuit, forced shutdown hardware circuits, hardware forced shutdown time adjusting circuit and key press detecting circuit, wherein:

[0006] 所述电源以及过流保护电路:实现后级电路工作异常所出现的短路或耗电过大现象时,达到关断电源保护后级电路的作用; [0006] The overcurrent protection circuit and a power source: when the short-circuit abnormality occurring subsequent stage circuit or the phenomenon of excessive power consumption, turning off the power to the role of the protection circuit of the subsequent stage;

[0007] 所述开关机按键:实现手动触发硬件开机信号和触发软关机信号以及硬件强制关机; [0007] The switch button: to achieve manually trigger the trigger hardware and software power-off signal and hardware forced shutdown signal;

[0008] 所述硬件开机电路:实现手动触发开关机按键后传输开机信号的过程; [0008] The hardware power circuit: to achieve manually trigger the switch button of the start signal transmission process;

[0009] 所述硬件强制关机时间调节电路:实现强制关机的时间控制; [0009] The time adjusting circuit hardware forced shutdown: shutdown time control to achieve mandatory;

[0010] 所述按键检测电路:为控制器实现软关机提供触发信号; [0010] The key press detecting circuit: providing a trigger signal to the controller to achieve soft-off;

[0011] 所述软件关机电路:为控制器输出关机信号提供功能实现电路; [0011] The software shutdown circuit: the output function to provide the shutdown signal to the controller circuit implemented;

[0012] 所述硬件强制关机电路:当软关机失效时,达到随时准确关机的目的。 [0012] The hardware forced shutdown circuit: When soft-off failure, ready to achieve accurate shutdown purposes.

[0013] 优选地,所述电源以及过流保护电路具体为:电源为适配器和电池,适配器和电池的输出端分别通过二极管(D20)和二极管(D18)连接自恢复保险丝(Fl),所述自恢复保险丝(Fl)的输出端与功率MOS管(U28)的源极相连;所述功率MOS管(U28)的源极通过电阻(R150)与其栅极相连,所述功率MOS管(U28)的输出端,即漏极接有滤波电容(C75)以及滤波电容(C77),然后与负载相连。 [0013] Preferably, the power supply and the overcurrent protection circuit in particular: a battery power supply and the adapter, the adapter output and the battery are connected resettable fuse (Fl) via a diode (D20) and a diode (D18), the recovery from the source fuse (Fl) and the output terminal of the power MOS transistor (U28) is connected to the electrode; a source of the power MOS transistor (U28) is connected via a resistor (R150) connected to its gate, the power MOS (U28) an output terminal that is connected with the drain filter capacitor (C75) and a filter capacitor (C77), and then connected to the load.

[0014] 优选地,所述开关机按键(Kl)具体为:其一端连接脚(1、4)与所述功率MOS管(U28)的源极连接,另一端连接脚(2、3)分三路与硬件开机电路、硬件强制关机电路、按键检测电路的输入端并行连接。 [0014] Preferably, the switch button (Kl) is specifically: one end of the connecting leg (1,4) is connected with the power source MOS transistor (U28), and the other end of the connecting leg (3) minutes three-way power and hardware circuits, hardware forced shutdown circuit, the key input detecting circuit connected in parallel.

[0015] 优选地,所述硬件开机电路具体为:通过所述开关机按键(Kl)的连接脚(2、3)与二极管(D2)的正极连接,所述二极管(D2)负极通过电容(C158)连接至地,所述二极管(D2)负极还通过电阻(R96 )与功率MOS管(U16 )的栅极相连,所述功率MOS管(U16 )栅极通过电阻(R90)连接至地;所述功率MOS管(U16)源极接地,所述功率MOS管(U16)的漏极与所述功率MOS管(U28)的栅极连接。 [0015] Preferably, the hardware power-on circuit in particular: the connection pin through said key switch (Kl) (2,3) and the diode (D2) connected to an anode of the diode (D2) via a capacitor anode ( C158) connected to ground, said diode (D2) through a negative gate resistor (R96) and the power MOS (U16) is connected to said power MOS (U16) is connected to ground via a resistor gates (R90); the power MOS (U16) source grounded, and the power drain of the power MOS (U28) is connected to the gate of the MOS transistor (U16) of.

[0016] 优选地,所述软件关机电路具体为:其一端与主控IO 口相连,另一端直接与三极管(Ql)基极连接,所述三极管(Ql)的基极通过电容(C9)连接至地,所述三极管(Ql)的发射极直接接地,所述三极管(Ql)的集电极通过电阻(R7)与二极管(Dl)负极连接,所述二极管(Dl)的正极与VCC相连,所述三极管(Ql)的集电极还通过电阻(R151)与所述功率MOS管(U16)的栅极连接;所述功率MOS管(U16)的漏极与功率MOS管(U28)的栅极连接,所述功率MOS管(U16)的源极接地。 [0016] Preferably, the particular software shutdown circuit: one end connected to the master IO port, connected directly to the other end of the transistor (Ql,) group, the transistor (Ql,) connected to the base via a capacitor (C9) to the collector of the transistor (Ql,) emitter directly grounded, the transistor (Ql,) of the diode (Dl) cathode is connected through a resistor (R7) and a diode (Dl) cathode is connected to VCC, the a gate connected to the collector of said transistor (Ql,) through a resistor (R151) with the power MOS transistor (U16); said power MOS (U16) and the drain of power MOS (U28) is connected to the gate the power MOS (U16) of the source is grounded.

[0017] 优选地,所述硬件强制关机电路具体为:其输入端通过电阻(R155)与开关机按键(Kl)的连接脚(2、3)连接,所述电阻(R155)还与稳压管(U31)的第二脚连接,所述电阻(R155)还通过电阻(R154)与稳压管(U31)的第一脚连接;所述稳压管(U31)的第一通过电阻(R145)接地,所述稳压管(U31)的第三脚直接接地,所述稳压管(U31)的第二脚通过电容(C168)接地,所述稳压管(U31)的第二脚还通过电阻(R208)接至地,所述稳压管(U31)的第二脚还通过电阻(R207)与二极管(D15)连接;所述二极管(D15)的正极与电容(C170)正极连接;所述电容(C170)负极接地,所述电容(C170)的正极通过电阻(R209)与运放(U9)的第三脚连接,所述电容(C170)的正极还通过电容(C106)接至地;所述运放(U9)的第三脚还通过电阻(R210)连接至地,所述运放(U9)的第四脚接地,所述运放(U9)的第八脚与二极管(D15)的负极连接,所述运放(U9)的第 [0017] Preferably, the particular hardware forced shutdown circuit: having an input connected via a resistor (R155) and the key switch (Kl) connected to pin (3), the resistor (R155) and is also regulated a first leg connecting pipe (U31) is connected to a second pin, said resistor (R155) through a resistor (R154) and the regulator (U31); said regulator (U31) via a first resistor (R145 second pin directly to ground the third pin) to ground, said zener diode (U31), said regulator (U31) via a capacitor (C168) to ground, said regulator (U31) is also a second leg connected through a resistor (R208) to ground, the second leg regulator (U31) further diode (D15) is connected via a resistor (R207 in); said diode (D15) cathode and a capacitor (C170) connected to the positive electrode; the capacitance (C170) negative ground, the positive electrode of the capacitor (C170) via a resistor (R209) and the operational amplifier (U9) is connected to the third pin, a positive electrode of the capacitor (C170) is also connected via a capacitor (C106) to ground; of the operational amplifier (U9) is also connected to the third pin through a resistor (R210), said operational amplifier (U9) fourth pin grounded, said amplifier (U9) and an eighth pin diode ( D15) connected to the negative, the operational amplifier (U9) of 脚还与二极管(D8)和二极管(D9)的负极连接;所述二极管(D8)的正极与开关机按键(Kl)的连接脚(2、3)相连,所述二极管(D9)的正极与VCC连接;所述运放(U9)的第一脚通过电阻(R158)与三极管(Q12)基极连接;所述三极管(Q12)的基极通过电阻(R211)连接至地,所述三极管(Q12)的发射极接地,所述三极管(Q12)的集电极与所述功率MOS管(U16)的栅极连接;所述运放(U9)的第二脚通过电阻(R213)与稳压管(U43)的第二脚连接;所述的稳压管(U43)的第二脚与自身的第二脚相连,所述稳压管(U43)的第一脚还通过电阻(R212)与开关机按键(Kl)的连接脚(2、3)连接; Is also connected to the negative pin diode (D8) and a diode (D9); said diode (D8) anode and the key switch (Kl) connected to pin (3), said diode (D9) cathode and VCC; said operational amplifier (U9) a first leg connected through a resistor (R158) of the transistor (Q12) group; the transistor (Q12) the base resistor (R211) is connected to earth via the transistor ( Q12) of the emitter grounded, the transistor (Q12) and a collector connected to the gate of the power MOS transistor (U16); a second leg of the operational amplifier (U9) through a resistor (R213) and the regulator (U43) of a second connecting pin; said regulator (U43) and the second leg is connected to its second leg, the first leg of the voltage regulator (U43) through a resistor (R212) and the switch machine key (Kl) is connected to pin (3) is connected;

[0018] 优选地,所述硬件强制关机时间调节电路具体为:属于硬件强制关机电路的一部分,其关机时间t=RC,即t=R207*C170。 [0018] Preferably, the hardware forced shutdown time adjusting circuit specifically includes: a hardware part forced shutdown circuit which shutdown time t = RC, i.e., t = R207 * C170.

[0019] 优选地,所述按键检测电路具体为:其输入端通过电阻(R124)连接三极管(Q9)的基极,所述三极管(Q9)的基极通过电容(C109)接至地,所述三极管(Q9)的集电极接VCC,所述三极管(Q9)的发射极通过电阻(R125)接地,所述三极管(Q9)的发射极还通过电阻(R132)连接微控制单元(MCU)的IO 口,所述微控制单元(MCU)的IO 口通过电阻(R131)下拉至地。 [0019] Preferably, the key press detecting circuit specifically: an input terminal through a resistor (R124) connected transistor (Q9) the base of the transistor (Q9) the base via a capacitor (C109) to ground, the said transistor (Q9) is connected to the collector of the VCC, the transistor (Q9) emitter through a resistor (of R125) to ground, the transistor (Q9) is also connected to the emitter of a micro control unit (MCU) through a resistor (R132) of IO ports, the micro control unit (MCU) of the IO port through a resistor (R131) down to the ground. [0020] 与现有技术相比,本发明提供的硬开关机系统,硬件关机时间可控,关机状态可检测,待机几乎零功耗的简单,安全可靠。 [0020] Compared with prior art, hard switching system provided by the present invention, the hardware controlled shutdown time, the off state can be detected, almost zero standby power simple, safe and reliable.

附图说明 BRIEF DESCRIPTION

[0021] 图1为本发明实施例中硬开关机系统的原理框图; [0021] FIG. 1 a block diagram of the principle of hard-switching system of the embodiment of the present invention;

[0022] 图2为本发明实施例中硬开关机系统的电路结构图。 [0022] Fig 2 a circuit configuration diagram of the hard switch system embodiment of the invention.

具体实施方式 detailed description

[0023] 为了本领域的技术人员能够更好地理解本发明所提供的技术方案,下面结合具体实施例进行阐述。 [0023] In order that those skilled in the art to better understand the technical solutions provided by the present invention, the following example will be described with reference to specific embodiments.

[0024] 请参见图1和图2,图1为本发明实施例中硬开关机系统的原理框图;图2为本发明实施例中硬开关机系统的电路结构图。 [0024] Referring to FIG. 1 and FIG. 2 block diagram, FIG. 1 embodiment a hard switching system embodiment of the present invention; Figure 2 a circuit diagram showing the construction of the hard-switching system of the present embodiment of the invention.

[0025] 本发明实施例提供的硬开关机系统,包括电源以及过流保护电路、开关机按键、硬件开机电路、软件关机电路、硬件强制关机电路、硬件强制关机时间调节电路和按键检测电路,其中: Hard switching system embodiment provided in the [0025] present invention, including the power supply and the overcurrent protection circuit, switch button, power circuit hardware, software shutdown circuits, hardware forced shutdown circuit, a hardware circuit and a forced shutdown time adjustment key press detecting circuit, among them:

[0026] 电源以及过流保护电路:实现后级电路工作异常所出现的短路或耗电过大现象时,达到关断电源保护后级电路的作用;开关机按键:实现手动触发硬件开机信号和触发软关机信号以及硬件强制关机;硬件开机电路:实现手动触发开关机按键后传输开机信号的过程;硬件强制关机时间调节电路:实现强制关机的时间控制;按键检测电路:为控制器实现软关机提供触发信号;软件关机电路:为控制器输出关机信号提供功能实现电路;硬件强制关机电路:当软关机失效时,达到随时准确关机的目的。 [0026] The overcurrent protection circuit and power supply: subsequent stage circuit implemented when an abnormality occurring phenomenon of short circuit or too large power consumption, turning off the power to the role after stage protection circuit; switch button: hardware implemented manually trigger signal and start soft and hardware shutdown signal trigger forced shutdown; hardware power circuit: to achieve manually trigger the switch button of the start signal transmission process; hardware forced shutdown time adjusting circuit: to achieve forced shutdown time control; key press detecting circuit: soft-shutdown controller is providing a trigger signal; software shutdown circuit: providing a controller output circuit functions to achieve the shutdown signal; hardware forced shutdown circuit: when soft-off failure, ready to achieve accurate shutdown purposes.

[0027] 电源以及过流保护电路:电源为适配器和电池,适配器和电池的输出端分别通过二极管D20和二极管D18连接自恢复保险丝F1,自恢复保险丝Fl的输出端与功率MOS管U28的源极相连;功率MOS管U28的源极通过电阻R150与其栅极相连,功率MOS管U28的输出端,即漏极接有滤波电容C75以及滤波电容C77,然后与负载相连; Output of the power source and the output terminal of the battery to the adapter, the adapter and the battery are connected resettable fuse F1 through the diode D20 and the diode D18, the resettable fuse Fl pole power MOS U28: [0027] The overcurrent protection circuit and a power supply connected; U28 power MOS source through a resistor R150 and its gate connected to the output terminal of the power MOS transistor U28, i.e., filter capacitor C75 is connected with the drain and a filter capacitor C77, and then connected to a load;

[0028] 开关机按键Kl:其一端连接脚1、4与功率MOS管U28的源极连接,另一端连接脚 [0028] The switch button Kl: pin 4 having one end connected to the source of power MOS U28 is connected, the other end of the connecting leg

2、3分三路与硬件开机电路、硬件强制关机电路、按键检测电路的输入端并行连接; 2,3 power in three columns and hardware circuits, hardware forced shutdown circuit, the key input detecting circuit connected in parallel;

[0029] 硬件开机电路:通过开关机按键Kl的连接脚2、3与二极管D2的正极连接,二极管D2负极通过电容C158连接至地,二极管D2负极还通过电阻R96与功率MOS管U16的栅极相连,功率MOS管U16栅极通过电阻R90连接至地;功率MOS管U16源极接地,功率MOS管U16的漏极与功率MOS管U28的栅极连接; [0029] Hardware power circuit: through the connection pin connected to the positive 2 and 3 and the diode D2 switch key Kl, the cathode of the diode D2 is connected to ground via a capacitor C158, a diode D2 the anode through a resistor R96 and further the gate of power MOS transistor of U16 connected to the gate of power MOS U16 through a resistor R90 connected to the ground; power MOS source grounded U16, U16 power MOS drain of power MOS gate U28 is connected;

[0030] 软件关机电路:其一端与主控IO 口相连,另一端直接与三极管Ql基极连接,三极管Ql的基极通过电容C9连接至地,三极管Ql的发射极直接接地,三极管Ql的集电极通过电阻R7与二极管Dl负极连接,二极管Dl的正极与VCC相连,三极管Ql的集电极还通过电阻R151与功率MOS管U16的栅极连接;功率MOS管U16的漏极与功率MOS管U28的栅极连接,功率MOS管U16的源极接地; [0030] software shutdown circuit: one end connected to the master IO port, and the other end is connected directly to the base of the transistor Ql, the base of transistor Ql is connected to ground via a capacitor C9, emitter of transistor Ql is connected directly to ground, the collector of transistor Ql a negative electrode through a resistor R7 and the diode Dl is connected, the diode Dl is connected to the positive electrode and the VCC, the collector of transistor Ql is also connected to gate of U16 through the resistor R151 of the power MOS; U16 power MOS drain of the power MOS U28 connected to the gate, source power MOS U16 is grounded;

[0031] 硬件强制关机电路:其输入端通过电阻R155与开关机按键Kl的连接脚2、3连接,电阻R155还与稳压管U31的第二脚连接,电阻R155还通过电阻R154与稳压管U31的第一脚连接;稳压管U31的第一通过电阻R145接地,稳压管U31的第三脚直接接地,稳压管U31的第二脚通过电容C168接地,稳压管U31的第二脚还通过电阻R208接至地,稳压管U31的第二脚还通过电阻R207与二极管D15连接;二极管D15的正极与电容C170正极连接;电容C170负极接地,电容C170的正极通过电阻R209与运放U9的第三脚连接,电容C170的正极还通过电容C106接至地;运放U9的第三脚还通过电阻R210连接至地,运放U9的第四脚接地,运放U9的第八脚与二极管D15的负极连接,运放U9的第八脚还与二极管D8和二极管D9的负极连接;二极管D8的正极与开关机按键Kl的连接脚2、3相连,二极管D9的正极与VCC连接;运放U9的第一脚通过 [0031] Hardware forced shutdown circuit: an input terminal 3 via a resistor R155 is connected to the pin of Kl switch button, is also connected to resistor R155 regulator U31 of the second leg, the resistor R154 and the resistor R155 through the regulator a first leg connected to U31; U31 regulator through a first resistor R145 is grounded directly to ground the third pin of regulator U31, U31 second leg by the first zener diode capacitor C168 is grounded, the regulator U31 two feet is also connected through resistor R208 to the second leg, the regulator U31 is also connected via a resistor R207 and diode D15; D15, the diode cathode connected to the positive electrode capacitor C170; C170 negative ground capacitance of the positive electrode, the capacitor C170 through resistor R209 and a third operational amplifier U9 pin connector, the positive electrode of the capacitor C170 is also connected to ground via the capacitor C106; U9 third pin of the op amp is also connected to ground via a resistor R210, a fourth operational amplifier U9 ground pin, a first operational amplifier U9 of negative diode D15 is connected to the eight-foot, eight foot U9 operational amplifier is also connected to the negative diode D8 and the diodes D9; diode D8 anode and the key switch Kl connected to the connecting legs 2,3, diode D9 cathode and VCC is connected; a first operational amplifier U9 by foot 阻R158与三极管Q12基极连接;三极管Q12的基极通过电阻R211连接至地,三极管Q12的发射极接地,三极管Q12的集电极与功率MOS管U16的栅极连接;运放U9的第二脚通过电阻R213与稳压管U43的第二脚连接;的稳压管U43的第二脚与自身的第二脚相连,稳压管U43的第一脚还通过电阻R212与开关机按键Kl的连接脚2、3连接; Resistor R158 is connected to the base of transistor Q12; Q12 is the transistor base connected to ground via a resistor R211, the emitter of the transistor Q12 is grounded, and the collector of the transistor Q12 is connected to the gate of the power MOS transistor of U16; op-amp U9 second leg resistor R213 is connected via a second pin of the regulator U43; U43 pin of the second regulator is connected with its second leg, the first leg of the regulator U43 is also connected through a resistor R212 and a switch button Kl 2,3 foot connection;

[0032] 硬件强制关机时间调节电路:属于硬件强制关机电路的一部分,其关机时间t=RC,即t=电阻R207* 电容C170 ; [0032] Hardware forced shutdown time adjusting circuit: a hardware part forced shutdown circuit which shutdown the RC t = time, i.e. t = capacitance resistor R207 * C170;

[0033] 按键检测电路:其输入端通过电阻R124连接三极管Q9的基极,三极管Q9的基极通过电容C109接至地,三极管Q9的集电极接VCC,三极管Q9的发射极通过电阻R125接地,三极管Q9的发射极还通过电阻R132连接微控制单元MCU的IO 口,微控制单元MCU的IO口通过电阻Rl31下拉至地。 [0033] The key press detecting circuit: having an input connected to base of the transistor Q9 through the resistor R124 of the electrode, the transistor Q9 base via a capacitor C109 to ground, the collector of the transistor Q9 is connected to the VCC, the emitter of transistor Q9 to ground through resistor R125, the emitter of transistor Q9 through the resistor R132 is connected to electrode microcontroller unit MCU IO port, the microcontroller unit MCU IO port down to the ground through a resistor Rl31.

[0034] 本实施例中,本发明提供的硬开关机系统的动作过程如下: [0034] In this embodiment, during the operation of the hard switching system according to the present invention are as follows:

[0035] I)、硬件开机: [0035] I), hardware power:

[0036] 未开机时,当开关机按键Kl按下,开关机按键Kl的连接脚2、3接通电源适配器或电池,此时高电平通过二极管D2以及电阻R96导向功率MOS管U16的栅极,此时功率MOS管U16的栅极置高,使得功率MOS管U16导通,其漏极电平置低并导致功率MOS管U28导通,随后VCC得以供电,VCC再经过二极管Dl以及电阻R7、电阻R151来置高功率MOS管的栅极,维持功率MOS管U16处于导通状态,最终实现开机。 [0036] is not turned on, when the switch button is pressed Kl, Kl switch button 3 is connected to pin power adapter or battery pack, by a high level at this time the diode D2 and the resistor R96 the gate guide of the power MOS U16 electrode, at this time a high gate opposite the power MOS U16, U16 such that the power MOS transistor is turned on, the drain of low level of the set and cause the power MOS U28 is turned on, then the power supply to VCC, VCC and then through the diode Dl and a resistor R7, a resistor R151 to the gate of a high power MOS, power MOS is maintained in the on state U16, ultimately boot.

[0037] 2)、按键检测: [0037] 2), key detection:

[0038] 开机后,当开关机按键Kl按下,产生高电平,通过Rl24开通三极管Q9,随后VCC通过电阻R131与电阻R132进行分压后输出到微控制单元MCU进行采集,检测到高电平即为开关机按键Kl按下;开关机按键Kl松开后,微控制单元MCU采集到的是低电平。 [0038] When turned on, when the switch button is pressed Kl, generating a high level, by opening Rl24 transistor Q9, and then outputs the VCC to the microcontroller unit MCU after collection by dividing resistor R131 and the resistor R132, detects a high electrical Kl is the level switch button is pressed; Kl ​​release the switch button, the microcontroller unit MCU collected is low.

[0039] 3)、软件关机: [0039] 3), software shutdown:

[0040] 开机后,MCU根据自身要求,可以输出高电平来使三极管Ql导通,然后拉低功率MOS管U16,致使功率MOS管U16截止而达到关闭功率MOS管U28,实现软件关机。 [0040] After the start, the MCU according to their own requirements, may output the high level to the transistor Ql is turned on, then the power MOS down U16, U16 is turned off so that power MOS power MOS achieve close U28, implementing software shutdown.

[0041] 4)、硬件强制关机: [0041] 4), hardware forced shutdown:

[0042] 开机后,假如软关机失效或微控制单元MCU死机,可以长按开关机按键K1,电平通分两路流向运放U9的第二脚和第三脚,流向运放U9的第二脚电平通过电阻R212与稳压管U43处理后输出一个固定电平2.5V,该固定电平作为基准电压源输出到运放U9的第二脚;流向运放U9的第三脚电平通过电阻R155、电阻R154、电阻R145与稳压管U31处理后输出 [0042] When turned on, if a soft shutdown or failure of the microcontroller unit MCU crash, can press switch button K1, level two routes flow through the second operational amplifier and a third leg foot U9, U9 flow of the operational amplifier two foot level processed output a fixed level through the resistor R212 and 2.5V regulator U43, the output level is fixed as a reference voltage source to a second operational amplifier U9 foot; a third pin op amp U9 flow level via the resistor R155, resistor R154, resistor R145 and the processed output regulator U31

6.25V电平,随后经过电阻R207给电容C170充电,充电电平经过电阻R207、电阻R209与电阻R210分压后输出至运放U9的第三脚,当电平超过运放U9的第二脚基准电压2.5V时,运放U9的第一脚由原来的低电平变为高电平,高电平通过电阻R158开通三极管Q12,由三极管Q12拉低功率MOS管U16的栅极,此时功率MOS管U16截止,从而达到关闭功率MOS管U28,实现硬件强制关机。 6.25V level, then through resistor R207 to capacitor C170, the charging level via the resistor R207, the resistor R209 and the resistor R210 divided voltage output to the operational amplifier U9 of the third pin, when the level exceeds the amplifier's second foot U9 when the reference voltage is 2.5V, the low level of the first operational amplifier U9 foot from the original becomes a high level, the transistor Q12 high through the resistor R158 open, power MOS gate U16 is pulled low by transistors Q12, at this time U16 power MOS is turned off, so as to turn off the power MOS transistor U28, hardware forced shutdown.

[0043] 关于RC延时电路的补充说明: [0043] For the RC delay circuit is added:

[0044] RC延时电路时间的计算,简单的方法就是t=RC,即RC回路的时间常数,在充电时,每过一个t的时间,电容器上电压就上升(l-1/e)约等于0.632倍的输入源电压(即本发明电路中电阻R208上的电压)与电容器电压(本发明电路电容C170上的电压)之差;在本发明电路中为把硬件关机时间控制在t=RC=R208*C170=100*10~3*(33/l(T6)=3.3秒,那么运放U9的第三脚输入电压必须在3.3秒的时间内超过第二脚的输入电压。根据这个理论,合理设置电阻R207、电阻R209、电阻R210的阻值,即可设计出精确可控的硬件关机时间。 [0044] Calculation of the RC time delay circuit, a simple method is t = RC, i.e., the time constant of the RC circuit, during charging, each over a period of time t, the capacitor voltage rises (l-1 / e) of about is equal to 0.632 times the input source voltage (i.e. voltage across the resistor R208 circuit of the present invention) and the capacitor voltage (voltage at circuit capacitor C170 according to the present invention) of; the circuit of the present invention, as the hardware shutdown time control t = RC = R208 * C170 = 100 * 10 ~ 3 * (33 / l (T6) = 3.3 seconds, a third operational amplifier U9 pin input voltage of the second voltage input pin must exceed 3.3 seconds. according to this theory reasonable setting resistor R207 in, resistor R209, resistor R210 resistance, can be designed precisely controllable hardware shutdown time.

[0045] 关于待机电流的补充说明: [0045] Supplementary explanation on standby current:

[0046] 本电路在关机状态下,实测有少于20uA的静耗电,主要是出自功率MOS管,大小取自上拉电阻R150,如果还需减少静耗电大小,可采取增大阻值的方式,但其关断能力随之降低,所以可根据实际进行调整,而本实施例的电路取其典型值10K。 [0046] The present circuit is in the off state, there is less than 20uA Found static power consumption, primarily by power MOS, from the size of pull-up resistor R150, if the need to reduce the size of the static power consumption, can be taken to increase the resistance manner, but decreases its ability to turn-off, it can be adjusted according to actual, and the circuit according to the present exemplary embodiment whichever value is 10K.

[0047] 与现有技术相比,本发明提供的硬开关机系统,硬件关机时间可控,关机状态可检测,待机几乎零功耗的简单,安全可靠,具体而言,具有以下优点: [0047] Compared with the prior art, the present invention provides hard switching systems, hardware controlled shutdown time, the shutdown state can be detected, almost zero standby power simple, safe and reliable, in particular, has the following advantages:

[0048] 1、全部采用分立器件组成,电路简单,运行安全可靠,比现在同功能应用电路有着更低的待功耗,实测低于20uA ; [0048] 1, all using discrete components, the circuit is simple, safe and reliable operation, with power to be lower than the current application circuit with the function, found less than 20uA;

[0049] 2、本发明为防止软件关机失灵的情况,增加了硬件强制关机,使得产品安全性得以大大提升,维护得到更大方便; [0049] 2, the present invention is to prevent failure shutdown software, hardware forced shutdown increased, so that the product can be greatly enhanced safety, easy to maintain greater;

[0050] 3、本发明的硬件关机时间可控,t=RC,更适用于现代医疗设备对用户配置数据以及正在处理的关键数据得能够及时加以保存的特殊要求。 [0050] 3, the present invention is hardware controlled shutdown time, t = RC, the medical device is more suitable for modern user configuration data and key data are processed to give them special requirements can be saved in a timely manner.

[0051] 对所公开的实施例的上述说明,使本领域专业技术人员能够实现或使用本发明。 [0051] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. 对这些实施例的多种修改对本领域的专业技术人员来说将是显而易见的,本文中所定义的一般原理可以在不脱离本发明的精神或范围的情况下,在其它实施例中实现。 Various modifications to these professionals skilled in the art of the present embodiments will be apparent, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. 因此,本发明将不会被限制于本文所示的这些实施例,而是要符合与本文所公开的原理和新颖特点相一致的最宽的范围。 Accordingly, the present invention will not be limited to the embodiments shown herein but is to be accorded herein consistent with the principles and novel features disclosed widest scope.

Claims (8)

1.一种硬开关机系统,其特征在于,包括电源以及过流保护电路、开关机按键、硬件开机电路、软件关机电路、硬件强制关机电路、硬件强制关机时间调节电路和按键检测电路,其中: 所述电源以及过流保护电路:实现后级电路工作异常所出现的短路或耗电过大现象时,达到关断电源保护后级电路的作用; 所述开关机按键:实现手动触发硬件开机信号和触发软关机信号以及硬件强制关机; 所述硬件开机电路:实现手动触发开关机按键后传输开机信号的过程; 所述硬件强制关机时间调节电路:实现强制关机的时间控制; 所述按键检测电路:为控制器实现软关机提供触发信号; 所述软件关机电路:为控制器输出关机信号提供功能实现电路; 所述硬件强制关机电路:当软关机失效时,达到随时准确关机的目的。 A hard switching system, characterized in that the overcurrent protection circuit comprises a power supply and, switch button, power circuit hardware, software shutdown circuits, hardware forced shutdown circuit, a hardware circuit and a forced shutdown time adjustment key press detecting circuit, wherein : the overcurrent protection circuit and power supply: subsequent stage circuit implemented occurring abnormal phenomenon of excessive consumption or short circuit, to the role of post-stage circuit protection powered off; the switch button: hardware implemented manually triggered power soft-off signal and a trigger signal and a forced shutdown hardware; hardware power on the circuit: to achieve manually trigger the switch button start signal transmission process; the hardware forced shutdown time adjusting circuit: to achieve forced shutdown time control; the key detection circuit: soft-shutdown controller providing a trigger signal; said software shutdown circuit: providing a controller output circuit functions to achieve the shutdown signal; said hardware forced shutdown circuit: when soft-off failure, ready to achieve accurate shutdown purposes.
2.根据权利要求1所述的硬开关机系统,其特征在于,所述电源以及过流保护电路具体为:电源为适配器和电池,适配器和电池的输出端分别通过二极管(D20)和二极管(D18)连接自恢复保险丝(Fl),所述自恢复保险丝(Fl)的输出端与功率MOS管(U28)的源极相连;所述功率MOS管(U28)的源极通过电阻(R150)与其栅极相连,所述功率MOS管(U28)的输出端,即漏极接有滤波电容(C75)以及滤波电容(C77),然后与负载相连。 The hard switching system according to claim 1, wherein said power source, and the overcurrent protection circuit in particular: a battery power supply and the adapter, the adapter output and the battery, respectively, through a diode (D20) and a diode ( D18) connected resettable fuse (Fl), said self-recovery fuse source output terminal (Fl) and the power MOS (U28) is connected to the electrode; a source of the power MOS transistor (U28) is connected via a resistor (R150) and its a gate connected to the output terminal of the power MOS transistor (U28), that is connected with the drain filter capacitor (C75) and a filter capacitor (C77), and then connected to the load.
3.根据权利要求2所述的硬开关机系统,其特征在于,所述开关机按键(Kl)具体为:其一端连接脚(1、4)与所述功率MOS管(U28)的源极连接,另一端连接脚(2、3)分三路与硬件开机电路、硬件强制关机电路、按键检测电路的输入端并行连接。 The hard switching system according to claim 2, wherein said switch button (Kl) specifically includes: a source connected to one end of pin (4) with the power MOS transistor (U28) pole and the other end connected to pin (3) and three columns boot hardware circuits, hardware forced shutdown circuit, the key input detecting circuit connected in parallel. ` `
4.根据权利要求3所述的硬开关机系统,其特征在于,所述硬件开机电路具体为:通过所述开关机按键(Kl)的连接脚(2、3)与二极管(D2)的正极连接,所述二极管(D2)负极通过电容(C158 )连接至地,所述二极管(D2 )负极还通过电阻(R96 )与功率MOS管(U16 )的栅极相连,所述功率MOS管(U16)栅极通过电阻(R90)连接至地;所述功率MOS管(U16)源极接地,所述功率MOS管(U16)的漏极与所述功率MOS管(U28)的栅极连接。 The hard-switching system as claimed in claim 3, wherein the hardware power-on circuit is specifically: the positive electrode through the key switch (Kl) connected to pin (3) and the diode (D2) of connected to a diode (D2) connected to the negative electrode via a capacitor (C158) to ground, said diode (D2) is also connected to the anode gate of the power MOS transistor (U16) via a resistor (R96), a power MOS (U16 ) connected to the gate through a resistor (R90) to ground; the power MOS transistor (U16) source grounded, and the power drain of the power MOS (U28) is connected to the gate of the MOS transistor (U16) of.
5.根据权利要求4所述的硬开关机系统,其特征在于,所述软件关机电路具体为:其一端与主控IO 口相连,另一端直接与三极管(Ql)基极连接,所述三极管(Ql)的基极通过电容(C9)连接至地,所述三极管(Ql)的发射极直接接地,所述三极管(Ql)的集电极通过电阻(R7)与二极管(Dl)负极连接,所述二极管(Dl)的正极与VCC相连,所述三极管(Ql)的集电极还通过电阻(R151)与所述功率MOS管(U16)的栅极连接;所述功率MOS管(U16)的漏极与功率MOS管(U28)的栅极连接,所述功率MOS管(U16)的源极接地。 The hard-switching system as claimed in claim 4, wherein said software shutdown circuit specifically: one end connected to the master IO port, connected directly to the other end of the transistor (Ql,) group, the transistor a collector (Ql,) of the base via a capacitor (C9) connected to ground, the transistor (Ql,) emitter directly grounded, the transistor (Ql,) connected to the diode (Dl) cathode through a resistor (R7), the VCC is connected to the positive electrode and a gate connected to said diode (Dl) of the transistor (Ql,) through collector resistor (R151) with the power MOS transistor (U16); and a drain of the power MOS transistor (U16) of and electrode power MOS (U28) is connected to the gate of the power MOS transistor source (U16) is grounded.
6.根据权利要求5所述的硬开关机系统,其特征在于,所述硬件强制关机电路具体为:其输入端通过电阻(R155)与开关机按键(Kl)的连接脚(2、3)连接,所述电阻(R155)还与稳压管(U31)的第二脚连接,所述电阻(R155)还通过电阻(R154)与稳压管(U31)的第一脚连接;所述稳压管(U31)的第一通过电阻(R145)接地,所述稳压管(U31)的第三脚直接接地,所述稳压管(U31)的第二脚通过电容(C168)接地,所述稳压管(U31)的第二脚还通过电阻(R208)接至地,所述稳压管(U31)的第二脚还通过电阻(R207)与二极管(D15)连接;所述二极管(D15)的正极与电容(C170)正极连接;所述电容(C170)负极接地,所述电容(C170)的正极通过电阻(R209)与运放(U9)的第三脚连接,所述电容(C170)的正极还通过电容(C106)接至地;所述运放(U9)的第三脚还通过电阻(R210)连接至地,所述运放(U9)的第四脚接地,所述运放(U9)的第八脚与二极 The hard-switching system as claimed in claim 5, wherein said hardware is specifically forced shutdown circuit: an input terminal through a resistor (R155) and the key switch (Kl) connected to pin (3) connected to a resistor (R155) connected to the second leg further zener diode (U31), said resistor (R155) connected to the first leg further zener diode (U31) via a resistor (R154); the stable pressure pipe directly to ground the third pin (U31) via a first resistor (R145) to ground, said zener diode (U31), said regulator (U31) by the second leg capacitance (C168) to ground, the the second leg of said zener diode (U31) is also connected through a resistor (R208) to ground, the second leg regulator (U31) further diode (D15) is connected via a resistor (R207 in); said diode ( D15) the positive electrode of the capacitor (C170) connected to the positive electrode; the capacitor (C170) negative ground, the positive electrode of the capacitor (C170) via a resistor (R209) and the operational amplifier (U9) is connected to the third pin, said capacitor ( C170) is also connected to the positive electrode through a capacitance (C106) to ground; the operational amplifier (U9) is also connected to the third pin through a resistor (R210), said operational amplifier (U9) fourth pin is grounded, the operational amplifier (U9) and eighth pin diode 管(D15)的负极连接,所述运放(U9)的第八脚还与二极管(D8)和二极管(D9)的负极连接;所述二极管(D8)的正极与开关机按键(Kl)的连接脚(2、3)相连,所述二极管(D9)的正极与VCC连接;所述运放(U9)的第一脚通过电阻(R158)与三极管(Q12)基极连接;所述三极管(Q12)的基极通过电阻(R211)连接至地,所述三极管(Q12)的发射极接地,所述三极管(Q12)的集电极与所述功率MOS管(U16)的栅极连接;所述运放(U9)的第二脚通过电阻(R213)与稳压管(U43)的第二脚连接;所述的稳压管(U43)的第二脚与自身的第二脚相连,所述稳压管(U43)的第一脚还通过电阻(R212)与开关机按键(Kl)的连接脚(2、3)连接; A negative electrode tube (D15) is connected, said operational amplifier (U9) and eighth foot for the cathode of diode (D9) connected to a diode (D8); said diode (D8) anode and the switch button (Kl) of connecting leg (2,3), said diode (D9) cathode is connected to VCC; of the operational amplifier (U9) a first leg connected through a resistor (R158) of the transistor (Q12) group; the transistor ( Q12) via a base resistor (R211) coupled to ground, the transistor (Q12) of the emitter grounded, the transistor (Q12) and the collector of the power MOS transistor (U16) is connected to the gate; the a second operational amplifier pin (U9) by a second pin resistor (R213) and the regulator (U43) is connected; said regulator (U43) and the second leg of the second leg is connected to its own, the the first leg regulator (U43) is also connected through a resistor (R212) and the key switch (Kl) connected to pin (3);
7.根据权利要求6所述的硬开关机系统,其特征在于,所述硬件强制关机时间调节电路具体为:属于硬件强制关机电路的一部分,其关机时间t=RC,即t=R207*C170。 The hard switching system according to claim 6, wherein said time adjusting circuit hardware forced shutdown specifically: a hardware part forced shutdown circuit which shutdown time t = RC, i.e., t = R207 * C170 .
8.根据权利要求7所述的硬开关机系统,其特征在于,所述按键检测电路具体为:其输入端通过电阻(R124)连接三极管(Q9)的基极,所述三极管(Q9)的基极通过电容(C109)接至地,所述三极管(Q 9)的集电极接VCC,所述三极管(Q9)的发射极通过电阻(R125)接地,所述三极管(Q9)的发射极还通过电阻(R132)连接微控制单元(MCU)的IO 口,所述微控制单元(MCU)的IO 口通过电阻(R131)下拉至地。 8. The hard switching system according to claim 7, wherein said key detection circuit specifically: an input connected transistor (Q9) the base through a resistor (R124), the transistor (Q9) of base via a capacitor (C109) to ground, the transistor (Q 9) is connected to the collector of the VCC, the transistor (Q9) emitter through a resistor (of R125) to ground, the transistor (Q9) further emitter connecting micro control unit (MCU) through a resistor (R132) IO ports, the micro control unit (MCU) of the IO port through a resistor (R131) down to the ground.
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