CN202797879U - Overvoltage protection circuit - Google Patents
Overvoltage protection circuit Download PDFInfo
- Publication number
- CN202797879U CN202797879U CN 201220473737 CN201220473737U CN202797879U CN 202797879 U CN202797879 U CN 202797879U CN 201220473737 CN201220473737 CN 201220473737 CN 201220473737 U CN201220473737 U CN 201220473737U CN 202797879 U CN202797879 U CN 202797879U
- Authority
- CN
- China
- Prior art keywords
- bipolar transistor
- npn bipolar
- resistance
- pnp bipolar
- base stage
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model discloses an overvoltage protection circuit which comprises a voltage input end (VIN) and a voltage output end (VOUT). A first resistor (R1) is serially connected between the voltage input end (VIN) and the voltage output end (VOUT). The overvoltage protection circuit is characterized by further comprising a voltage regulator circuit parallelly connected with the first resistor (R1), the voltage regulator circuit comprises a first NPN bipolar triode (N1), a second NPN bipolar transistor (N2), a first PNP bipolar transistor (P1), a second PNP bipolar transistor (P2), a second resistor (R2), a third resistor (R3), a first avalanche diode or first Zener diode (D1) and a second avalanche diode or second Zener diode (D2). The overvoltage protection circuit has the advantages that the circuit is simple in structure, fewer devices and nodes are needed, cost and power consumption are reduced, and the risk of bad points is decreased.
Description
Technical field
The utility model relates to a kind of overvoltage crowbar.
Background technology
The needed voltage of portable type electronic product is generally lower, is 1.5V, 2.5V, 3.3V or 5V voltage generally speaking.In circuit, since the factor such as circuit signal is interfered, short circuit or supply power voltage are unstable, the situation that may cause voltage to raise suddenly, and too high voltage can affect the performance of circuit, burns out in addition the risk of circuit.
Overvoltage crowbar is the necessary circuitry that solves the problem of overvoltage, the complicated structure of the circuit of prior art, and required device and node are more, and device causes cost and power consumption higher more, and node is more to cause having a big risk of bad point.
The utility model content
Goal of the invention of the present utility model is: for the problem of above-mentioned existence, provide a kind of simple in structure, overvoltage crowbar that node is few.
The technical solution adopted in the utility model is such: a kind of overvoltage crowbar; comprise voltage input end and voltage output end; serial connection one first resistance between voltage input end and voltage output end; comprise also and described the first resistance regulating circuit in parallel that described regulating circuit comprises a NPN double pole triode, the 2nd NPN bipolar transistor, a PNP bipolar transistor, the 2nd PNP bipolar transistor, the second resistance, the 3rd resistance, the first avalanche diode or the first Zener diode, the second avalanche diode or the second Zener diode.Described the second resistance string is connected between the source electrode and base stage of a NPN bipolar transistor; Described voltage input end is connected to the base stage of a NPN bipolar transistor, the collector electrode of the 2nd PNP bipolar transistor and the positive terminal of the first avalanche diode or the first Zener diode; The negative pole end of described the first avalanche diode or the first Zener diode is connected to the base stage of collector electrode and the 2nd PNP bipolar transistor of a NPN bipolar transistor; Described voltage output end is connected to the source electrode of a NPN bipolar transistor and the source electrode of a PNP bipolar transistor; Between the base stage and source electrode of described the 3rd resistance serial connection and the 2nd NPN bipolar transistor; The positive terminal of the second avalanche diode or the second Zener diode is connected to the base stage of collector electrode and the 2nd NPN bipolar transistor of a PNP bipolar transistor, and negative pole end is connected to the base stage of a PNP bipolar transistor and the collector electrode of the 2nd NPN bipolar transistor; The source grounding of the source electrode of described the 2nd NPN bipolar transistor and the 2nd PNP bipolar transistor.
In sum, owing to adopted technique scheme, the beneficial effects of the utility model are: circuit structure is simple, and required device and node are less, reduce cost and power consumption, and reduces the bad point risk.
Description of drawings
Fig. 1 is the circuit theory diagrams of the utility model overvoltage crowbar.
Embodiment
Below in conjunction with accompanying drawing, the utility model is described in detail.
In order to make the purpose of this utility model, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the utility model is further elaborated.Should be appreciated that specific embodiment described herein only in order to explaining the utility model, and be not used in restriction the utility model.
As shown in Figure 1, be the circuit theory diagrams of the utility model overvoltage crowbar.
A kind of overvoltage crowbar of the present utility model; comprise voltage input end VIN and voltage output end VOUT; serial connection one first resistance R 1 between voltage input end VIN and voltage output end VOUT; comprise also and described the first resistance R 1 regulating circuit in parallel that described regulating circuit comprises a NPN double pole triode N1; the 2nd NPN bipolar transistor N2; the one PNP bipolar transistor P1; the 2nd PNP bipolar transistor P2; the second resistance R 2; the 3rd resistance R 3; the first avalanche diode or the first Zener diode D1; the second avalanche diode or the second Zener diode D2.
Be described in detail below in conjunction with the annexation between 1 pair of above-mentioned electronic devices and components of the utility model of accompanying drawing: described the second resistance R 2 is serially connected with between the source electrode and base stage of a NPN bipolar transistor N1; Described voltage input end VIN is connected to the base stage of a NPN bipolar transistor N1, the collector electrode of the 2nd PNP bipolar transistor P2 and the positive terminal of the first avalanche diode or the first Zener diode D1; The negative pole end of described the first avalanche diode or the first Zener diode D1 is connected to the collector electrode of a NPN bipolar transistor N1 and the base stage of the 2nd PNP bipolar transistor P2; Described voltage output end VOUT is connected to the source electrode of a NPN bipolar transistor N1 and the source electrode of a PNP bipolar transistor P1; Between the base stage and source electrode of described the 3rd resistance R 3 serial connections and the 2nd NPN bipolar transistor N2; The positive terminal of the second avalanche diode or the second Zener diode D2 is connected to the collector electrode of a PNP bipolar transistor P1 and the base stage of the 2nd NPN bipolar transistor N2, and negative pole end is connected to the base stage of a PNP bipolar transistor P1 and the collector electrode of the 2nd NPN bipolar transistor N2; The source grounding of the source electrode of described the 2nd NPN bipolar transistor N2 and the 2nd PNP bipolar transistor P2.
The above only is preferred embodiment of the present utility model; not in order to limit the utility model; all any modifications of within spirit of the present utility model and principle, doing, be equal to and replace and improvement etc., all should be included within the protection range of the present utility model.
Claims (1)
1. overvoltage crowbar, comprise voltage input end (VIN) and voltage output end (VOUT), serial connection one first resistance (R1) between voltage input end (VIN) and voltage output end (VOUT), it is characterized in that, comprise also and described the first resistance (R1) regulating circuit in parallel that described regulating circuit comprises a NPN double pole triode (N1), the 2nd NPN bipolar transistor (N2), the one PNP bipolar transistor (P1), the 2nd PNP bipolar transistor (P2), the second resistance (R2), the 3rd resistance (R3), the first avalanche diode or the first Zener diode (D1), the second avalanche diode or the second Zener diode (D2);
Described the second resistance (R2) is serially connected with between the source electrode and base stage of a NPN bipolar transistor (N1); Described voltage input end (VIN) is connected to the base stage of a NPN bipolar transistor (N1), the collector electrode of the 2nd PNP bipolar transistor (P2) and the positive terminal of the first avalanche diode or the first Zener diode (D1); The negative pole end of described the first avalanche diode or the first Zener diode (D1) is connected to the base stage of collector electrode and the 2nd PNP bipolar transistor (P2) of a NPN bipolar transistor (N1); Described voltage output end (VOUT) is connected to the source electrode of a NPN bipolar transistor (N1) and the source electrode of a PNP bipolar transistor (P1); Between the base stage and source electrode of described the 3rd resistance (R3) serial connection and the 2nd NPN bipolar transistor (N2); The positive terminal of the second avalanche diode or the second Zener diode (D2) is connected to the base stage of collector electrode and the 2nd NPN bipolar transistor (N2) of a PNP bipolar transistor (P1), and negative pole end is connected to the base stage of a PNP bipolar transistor (P1) and the collector electrode of the 2nd NPN bipolar transistor (N2); The source grounding of the source electrode of described the 2nd NPN bipolar transistor (N2) and the 2nd PNP bipolar transistor (P2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220473737 CN202797879U (en) | 2012-09-18 | 2012-09-18 | Overvoltage protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220473737 CN202797879U (en) | 2012-09-18 | 2012-09-18 | Overvoltage protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202797879U true CN202797879U (en) | 2013-03-13 |
Family
ID=47825057
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220473737 Expired - Fee Related CN202797879U (en) | 2012-09-18 | 2012-09-18 | Overvoltage protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202797879U (en) |
-
2012
- 2012-09-18 CN CN 201220473737 patent/CN202797879U/en not_active Expired - Fee Related
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203522681U (en) | Double-time-delay power-on sequential control circuit | |
| CN104536506B (en) | Linear voltage regulator | |
| CN203734283U (en) | Power supply protection circuit and power supply device | |
| CN104102318A (en) | Power source circuit | |
| CN202759379U (en) | Voltage stabilizing circuit | |
| CN203706005U (en) | Voltage stabilizing circuit | |
| CN103729005A (en) | Negative voltage regulating circuit | |
| CN103257665A (en) | Non-capacitive low-dropout linear voltage stabilizing system and bias current regulating circuit thereof | |
| CN202797879U (en) | Overvoltage protection circuit | |
| CN202797946U (en) | Overvoltage protection circuit | |
| CN202533829U (en) | Non-capacitance low-voltage-differential linear voltage stabilizing system and bias current adjusting circuit thereof | |
| CN202797951U (en) | Overvoltage protection circuit | |
| CN202586753U (en) | Inner power supply circuit for wind range power input | |
| CN202797956U (en) | Overvoltage protection circuit | |
| CN202455057U (en) | Power supply protecting circuit | |
| CN202797947U (en) | Overvoltage protection circuit | |
| CN103760942A (en) | Transient enhancement circuit applicable to low dropout regulator | |
| CN102789256B (en) | Low pressure difference linear voltage regulator | |
| CN203812130U (en) | Transient boosting circuit for low-voltage-difference linear voltage stabilizer and low-voltage-difference linear voltage stabilizer | |
| CN204536968U (en) | A kind of high power LD O circuit without external electric capacity | |
| CN103383579A (en) | Reference voltage source | |
| CN103683251A (en) | Overvoltage protection circuit | |
| CN103683183A (en) | Overvoltage protection circuit | |
| CN103683249A (en) | Overvoltage protection circuit | |
| CN103683248A (en) | Over-voltage protection circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130313 Termination date: 20130918 |