CN105162082A - Over-temperature protection circuit of uninterruptible power supply (UPS) charger - Google Patents
Over-temperature protection circuit of uninterruptible power supply (UPS) charger Download PDFInfo
- Publication number
- CN105162082A CN105162082A CN201510525996.2A CN201510525996A CN105162082A CN 105162082 A CN105162082 A CN 105162082A CN 201510525996 A CN201510525996 A CN 201510525996A CN 105162082 A CN105162082 A CN 105162082A
- Authority
- CN
- China
- Prior art keywords
- type triode
- pnp type
- charger
- pnp
- thermistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
An over-temperature protection circuit of an uninterruptible power supply (UPS) charger comprises a thermistor with a negative temperature coefficient, a positive-negative-positive (PNP) type triode and a negative-positive-negative (NPN) type triode, wherein the PNP type triode is used for outputting a high level to a control end after conducted, the NPN type triode is driven to be conducted by the PNP type triode for providing follow current to the NPN type triode, one end of the thermistor is grounded, the other end of the thermistor is connected with the base of the PNP type triode, a first resistor is connected in parallel onto the base and the emitter of the PNP type triode, a reference voltage is connected onto the emitter of the PNP type triode, the collector of the PNP type triode is connected with the control end for controlling whether the charger works or not, the collector of the PNP type triode is connected with the base of the NPN type triode, the collector of the NPN type triode is connected with the base of the PNP type triode, and a third resistor is connected in series onto the emitter of the NPN type triode. By the over-temperature protection circuit, the performance of the charger is prevented from being reduced, and the service life of the charger is prevented from being shortened.
Description
Technical field
The present invention relates to a kind of thermal-shutdown circuit of UPS charger.
Background technology
UPS charger is due to long-term work, and reliability requirement is very high, and its caloric value is large, and the rear device performance of heating declines and the life-span is lost, and is necessary for it and installs thermal-shutdown circuit additional.Existing common thermal-shutdown circuit, adopt thermistor directly to feed back, final temperature is in critical value, and switching device acts frequently, and shortens the life-span of charger, and causes hydraulic performance decline.
Summary of the invention
Even if the invention provides one charger to be warmed up to temperature protection critical point, switching device frequent movement is also there will not be to cause the thermal-shutdown circuit of the UPS charger in the life-span of hydraulic performance decline and reduction components and parts.
The technical solution used in the present invention is:
The thermal-shutdown circuit of UPS charger, it is characterized in that: the thermistor comprising a negative temperature coefficient, high level be exported to the PNP type triode of control end after conducting, by the NPN type triode that PNP type triode driving conducting is also its afterflow, one end ground connection of described thermistor, its other end is connected with the base stage of PNP type triode, the base stage of described PNP type triode and emitter are parallel with the first resistance, the emitter of described PNP type triode is connected with a reference voltage, its collector electrode with control charger operation whether control end and be connected, the collector electrode of described PNP type triode is connected with the base stage of NPN type triode, the collector electrode of described NPN type triode is connected with the base stage of PNP type triode, its emitter is serially connected with the 3rd resistance.Thermistor temp of the present invention is higher, and resistance value is lower, and thermistor is when normal temperature, and the electric current flowing through the first resistance is little, PNP type triode and NPN type triode all not conductings, and control end is without high level output, and charger normally works; When thermistor temp reaches preset temperature, on the first resistance, dividing potential drop just increases and makes PNP type triode conducting, and control end exports high level, controls charger and quits work; When thermistor temp drops to recovery temperature, flow through the undercurrent of thermistor and NPN type triode to maintain PNP type triode conducting, PNP type triode and NPN type triode are all ended, and control end is without high level output, and charger is resumed work.The present invention can allow charger under more mal-condition, after temperature rises to protection critical point, can not frequent switch, but just recovery when temperature drops to set point, the life-span of charger hydraulic performance decline and reduction components and parts can not be caused.
Further, between described thermistor and earth terminal, be serially connected with the second resistance, thermosensitive resistance too low damage PNP triode when preventing high temperature.
Further, the 4th resistance and diode is serially connected with between the collector electrode of described PNP type triode and control end.
The invention has the beneficial effects as follows: can allow charger under more mal-condition, after temperature rises to protection critical point, can not frequent switch, but just recovery when temperature drops to set point, the life-span of charger hydraulic performance decline and reduction components and parts can not be caused.
Accompanying drawing explanation
Fig. 1 is circuit theory diagrams of the present invention.
Embodiment
Below in conjunction with specific embodiment, the present invention is further described, but does not limit the invention to these embodiments.One skilled in the art would recognize that all alternatives, improvement project and the equivalents that present invention encompasses and may comprise in Claims scope.
With reference to Fig. 1, the thermal-shutdown circuit of UPS charger, comprise the thermistor NTC1 of a negative temperature coefficient, high level be exported to the PNP type triode Q1 of control end after conducting, by the NPN type triode Q2 that PNP type triode driving conducting is also its afterflow, one end ground connection of described thermistor NTC1, its other end is connected with the base stage of PNP type triode Q1, the base stage of described PNP type triode Q1 and emitter are parallel with the first resistance R1, the emitter of described PNP type triode Q1 is connected with a reference voltage V ref, its collector electrode with control charger operation whether control end Control and be connected, the collector electrode of described PNP type triode Q1 is connected with the base stage of NPN type triode Q2, the collector electrode of described NPN type triode Q2 is connected with the base stage of PNP type triode Q1, its emitter is serially connected with the 3rd resistance R3.Thermistor NTC1 temperature of the present invention is higher, and resistance value is lower, and thermistor NTC1 is when normal temperature, the electric current flowing through the first resistance R1 is little, PNP type triode Q1 and NPN type triode Q2 all not conductings, control end Control is without high level output, and charger normally works; When thermistor NTC1 temperature reaches preset temperature, on the first resistance R1, dividing potential drop just increases and makes PNP type triode Q1 conducting, and control end Control exports high level, and control charger quits work; When thermistor NTC1 temperature drops to recovery temperature, flow through the undercurrent of thermistor NTC1 and NPN type triode Q2 to maintain PNP type triode Q1 conducting, PNP type triode Q1 and NPN type triode Q2 all ends, and control end Control is without high level output, and charger is resumed work.The present invention can allow charger under more mal-condition, after temperature rises to protection critical point, can not frequent switch, but just recovery when temperature drops to set point, the life-span of charger hydraulic performance decline and reduction components and parts can not be caused.
The second resistance R2 is serially connected with between thermistor NTC1 and earth terminal, thermistor NTC1 value too low damage PNP triode Q1 when preventing high temperature described in the present embodiment.
The 4th resistance R4 and diode D1 is serially connected with between the collector electrode of PNP type triode Q1 described in the present embodiment and control end Control.
A first resistance R1 in parallel on the base stage of the PNP type triode Q1 of the present embodiment and emitter, its effect is connected with thermistor NTC1, the second resistance R2, and the first resistance R1 produces dividing potential drop, when dividing potential drop is more than 0.7V, the Q1 conducting of positive-negative-positive three pole.Make Vref be a constant reference voltage U, during temperature protection critical point, the resistance of thermistor NTC1 is Rt1, then the value of the first resistance R1 has following relational expression:
U*R1/ (R1+R2+Rt1)=0.7 (volt).
The present embodiment NPN type triode Q2, its base stage is connected to the collector electrode of PNP type triode Q1, and its collector electrode is connected to the base stage of PNP type triode Q1, and its emitter is connected in series a 3rd resistance R3.If the value of thermistor NTC1 is Rt2 when charger is resumed work from overheat protector, then the value of R3 has following relational expression:
R1［R3(R2+Rt2)+R1(R2+R3+Rt2)］=0.7(R1+R2+R3)。
Operation principle of the present invention is as follows:
A., under normal temperature, the resistance value ratio of thermistor NTC1 is comparatively large, and the electric current flowing through the first resistance R1 is little, dividing potential drop on first resistance R1 is less than 0.7V, PNP type triode Q1, NPN type triode Q2 all not conductings, control end Control is without high level output, and charger normally works.
B. when charger operation; its temperature constantly rises; the value of thermistor NTC1 constantly declines; dividing potential drop on first resistance R1 constantly rises; until when arriving preset temperature protection value T1, the dividing potential drop of R1 reaches 0.7V, causes PNP type triode Q1 conducting; control end Control exports as high level, controls charger and quits work.
C. under B state, NPN type triode Q2 is driven conducting by PNP type triode Q1, the electric current of the base-emitter flowing through the first resistance R1 and PNP type triode Q1 is caused to increase further, now charger quits work, temperature declines gradually, because there is NPN type triode Q2 to provide portion of electrical current, therefore PNP type triode Q1 keeps conducting.
D. when temperature drops to recovery temperature T2, the value of thermistor NTC1 increases to certain value, the total current flowing through thermistor NTC1 and NPN type triode Q2 is not enough to maintain PNP type triode Q1 conducting, PNP type triode Q1 ends, NPN type triode Q2 also ends owing to not having PNP type triode Q1 to provide electric current, control end Control is without high level output, and charger is resumed work, and enters next circulation.
Claims (3)
- The thermal-shutdown circuit of 1.UPS charger, it is characterized in that: the thermistor comprising a negative temperature coefficient, high level be exported to the PNP type triode of control end after conducting, by the NPN type triode that PNP type triode driving conducting is also its afterflow, one end ground connection of described thermistor, its other end is connected with the base stage of PNP type triode, the base stage of described PNP type triode and emitter are parallel with the first resistance, the emitter of described PNP type triode is connected with a reference voltage, its collector electrode with control charger operation whether control end and be connected, the collector electrode of described PNP type triode is connected with the base stage of NPN type triode, the collector electrode of described NPN type triode is connected with the base stage of PNP type triode, its emitter is serially connected with the 3rd resistance.
- 2. the thermal-shutdown circuit of UPS charger as claimed in claim 1, is characterized in that: be serially connected with the second resistance between described thermistor and earth terminal.
- 3. the thermal-shutdown circuit of UPS charger as claimed in claim 1 or 2, is characterized in that: be serially connected with the 4th resistance and diode between the collector electrode of described PNP type triode and control end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510525996.2A CN105162082A (en) | 2015-08-25 | 2015-08-25 | Over-temperature protection circuit of uninterruptible power supply (UPS) charger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510525996.2A CN105162082A (en) | 2015-08-25 | 2015-08-25 | Over-temperature protection circuit of uninterruptible power supply (UPS) charger |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105162082A true CN105162082A (en) | 2015-12-16 |
Family
ID=54802879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510525996.2A Pending CN105162082A (en) | 2015-08-25 | 2015-08-25 | Over-temperature protection circuit of uninterruptible power supply (UPS) charger |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105162082A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111817396A (en) * | 2020-07-20 | 2020-10-23 | 天能帅福得能源股份有限公司 | Circuit for simultaneously closing charging and discharging metal-oxide-semiconductor field effect transistors (MOSFETs) during high-temperature detection of protection plate |
| CN114043898A (en) * | 2021-10-18 | 2022-02-15 | 深圳市普兰斯通科技有限公司 | Charger protection circuit and method and charger |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6326849B1 (en) * | 2000-09-28 | 2001-12-04 | Eic Corporation | Isolation circuit for use in RF amplifier bias circuit |
| US20040165325A1 (en) * | 2003-02-24 | 2004-08-26 | Sunonwealth Electric Machine Industry Co., Ltd. | Over heat protection circuit for a brushless dc |
| US20100122976A1 (en) * | 2008-11-18 | 2010-05-20 | Electronics And Telecommunications Research Institute | Thermistor with 3 terminals, thermistor-transistor, circuit for controlling heat of power transistor using the thermistor-transistor, and power system including the circuit |
| CN102088183A (en) * | 2009-12-03 | 2011-06-08 | 晶洋微电子股份有限公司 | Protection circuit with locking control function |
| CN202103410U (en) * | 2011-06-30 | 2012-01-04 | 东莞市盈聚电子有限公司 | Over-temperature protection circuit of switch power supply |
| CN103840434A (en) * | 2012-11-22 | 2014-06-04 | 广东美的制冷设备有限公司 | Over-temperature protection circuit used for power module |
| CN204349432U (en) * | 2014-12-17 | 2015-05-20 | 广州金升阳科技有限公司 | A kind of Switching Power Supply thermal-shutdown circuit |
| CN204835485U (en) * | 2015-08-25 | 2015-12-02 | 深圳市商宇电子科技有限公司 | Excess temperature protection circuit of UPS charger |
-
2015
- 2015-08-25 CN CN201510525996.2A patent/CN105162082A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6326849B1 (en) * | 2000-09-28 | 2001-12-04 | Eic Corporation | Isolation circuit for use in RF amplifier bias circuit |
| US20040165325A1 (en) * | 2003-02-24 | 2004-08-26 | Sunonwealth Electric Machine Industry Co., Ltd. | Over heat protection circuit for a brushless dc |
| US20100122976A1 (en) * | 2008-11-18 | 2010-05-20 | Electronics And Telecommunications Research Institute | Thermistor with 3 terminals, thermistor-transistor, circuit for controlling heat of power transistor using the thermistor-transistor, and power system including the circuit |
| CN102088183A (en) * | 2009-12-03 | 2011-06-08 | 晶洋微电子股份有限公司 | Protection circuit with locking control function |
| CN202103410U (en) * | 2011-06-30 | 2012-01-04 | 东莞市盈聚电子有限公司 | Over-temperature protection circuit of switch power supply |
| CN103840434A (en) * | 2012-11-22 | 2014-06-04 | 广东美的制冷设备有限公司 | Over-temperature protection circuit used for power module |
| CN204349432U (en) * | 2014-12-17 | 2015-05-20 | 广州金升阳科技有限公司 | A kind of Switching Power Supply thermal-shutdown circuit |
| CN204835485U (en) * | 2015-08-25 | 2015-12-02 | 深圳市商宇电子科技有限公司 | Excess temperature protection circuit of UPS charger |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111817396A (en) * | 2020-07-20 | 2020-10-23 | 天能帅福得能源股份有限公司 | Circuit for simultaneously closing charging and discharging metal-oxide-semiconductor field effect transistors (MOSFETs) during high-temperature detection of protection plate |
| CN114043898A (en) * | 2021-10-18 | 2022-02-15 | 深圳市普兰斯通科技有限公司 | Charger protection circuit and method and charger |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100502195C (en) | Surge restraint circuit | |
| US20150026486A1 (en) | Overcurrent protection circuit and server using the same | |
| EP0501418A2 (en) | Low-fall voltage regulator | |
| CN102751700A (en) | Over-temperature protection circuit | |
| CN103281836A (en) | Chip over-temperature protection circuit applied to alternative current LED drive system | |
| CN109638774A (en) | A kind of thermal-shutdown circuit | |
| CN102693609A (en) | Electronic device with high temperature alarm function | |
| CN204835485U (en) | Excess temperature protection circuit of UPS charger | |
| CN204044656U (en) | A kind of stabilivolt and overheating protection circuit thereof | |
| CN105162082A (en) | Over-temperature protection circuit of uninterruptible power supply (UPS) charger | |
| CN108964191B (en) | Electric automobile charging control circuit with improved switch tube for overheat protection | |
| CN104754800B (en) | A kind of control device of LED modules inrush current | |
| CN102043413A (en) | Temperature control circuit | |
| CN204441858U (en) | A kind of temperature control circuit | |
| CN107425599B (en) | Surge protection circuit for power supply compensator | |
| CN202475387U (en) | Power-on reset POR circuit with variable reset voltage point, based on band gap reference source | |
| CN202977969U (en) | Efficient protection circuit of laser coupling power source | |
| CN209134294U (en) | A kind of started with high voltage and constant current circuit with temperature-compensating | |
| CN210380234U (en) | Direct current power supply input overcurrent protection circuit | |
| CN104571198A (en) | Sensitivity-adjustable temperature control circuit | |
| CN208753961U (en) | A kind of negative voltage protection circuit of power input over-voltage | |
| CN203691701U (en) | Device for controlling input surge current of LED module | |
| CN105515357B (en) | A kind of DCDC current-limiting circuits | |
| CN111064346B (en) | Linear power supply circuit with wide-range input voltage | |
| CN208971122U (en) | Overvoltage crowbar and power bus slave circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20151216 |