CN201069451Y - DC power load device - Google Patents
DC power load device Download PDFInfo
- Publication number
- CN201069451Y CN201069451Y CN 200720073679 CN200720073679U CN201069451Y CN 201069451 Y CN201069451 Y CN 201069451Y CN 200720073679 CN200720073679 CN 200720073679 CN 200720073679 U CN200720073679 U CN 200720073679U CN 201069451 Y CN201069451 Y CN 201069451Y
- Authority
- CN
- China
- Prior art keywords
- resistance
- stabilizing
- integrated package
- power
- pressure
- 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
- Continuous-Control Power Sources That Use Transistors (AREA)
Abstract
The utility model discloses a DC power supply load device which is characterized in that: the output end of a positive DC power supply is connected with an ammeter and then a resistor R1, an emitting electrode of a large-power triode V1, and a capacitor C1; the other end of the resistor R1 is connected with a base electrode of the large-power triode V1 and the input end Ui of a three-end adjustable series voltage-stabilizing integrated circuit; a collector electrode of the large-power triode V1 is connected with the output end U0 of the three-end adjustable series voltage-stabilizing integrated circuit and a resistor R2; and the other end of the capacitor C1, the other end of the resistor R2 and the adjusting end ADj of the three-end adjustable series voltage-stabilizing integrated circuit are all grounded. As a substitute for the pure resistance load, the utility model solves the problem that the over-high temperature of the power supply load box affects the accuracy of power supply test, and has the advantages of small shift of working current during long-term operation.
Description
Technical field
The utility model relates to a kind of load device of direct supply debugging usefulness.
Background technology
The utility model is used for a kind of debugging of answering machine power supply, and this power supply is :+12V; Output current 3.5A ± 5%;-12V output current 300mA ± 5%.At present, the power source loads of its debugging usefulness adopts high-power wire-wound fixed resistance, during debugging, power on this pull-up resistor has about 50W, because this wire-wound resistor is installed in the airtight iron-clad case, the temperature inside the box is high, reach more than 150 ℃, therefore cause that the gauge outfit shell that is contained in iron-clad case surface has the phenomenon of distortion, and in connect lead the adustion situation arranged, had a strong impact on the gauge outfit indication.In addition, wire-wound resistor is a positive temperature coefficient (PTC), and resistance also becomes big with the temperature rising for it.For example, performance assessment criteria is 2 hours, and in these 2 hours ,+12V output current drifts about in 3.210A～3.610A scope, no certain value; And-the 12V output current also changes in 280～330mA scope, had a strong impact on measuring accuracy.
Summary of the invention
For solve prior art power source loads oven temperature, rise too high, influence deficiency such as power supply test precision, the purpose of this utility model is to provide a kind of direct supply load device.The utility model is abandoned pure high-power resistance and is done load, provides one group of electronic devices and components to substitute.Not only solve the too high problem of temperature in the casing, and improved the adjustment accuracy of power supply.
In order to reach the foregoing invention purpose, the utility model is that the technical scheme that its technical matters of solution is adopted provides a kind of dc positive power load device, this device comprises: the output terminal of positive direct-current power supply is connected to the anode of reometer, the negative terminal of this reometer is with the emitter of resistance R 1, large power triode V1, and capacitor C 1 connects; The other end of resistance R 1 is connected with the base stage of large power triode V1 and the input end Ui of three end adjustable series integrated package of pressure-stabilizing; The collector of large power triode V1 is connected with resistance R 2 with the output terminal U0 of three end adjustable series integrated package of pressure-stabilizing; The adjustment end ADj ground connection of the other end of the other end of capacitor C 1, resistance R 2 and three end adjustable series integrated package of pressure-stabilizing.
In order to reach the foregoing invention purpose, for solving its technical matters, on the other hand of the present utility model, a kind of dc negative supply load device also is provided, this device comprises: the output of negative direct supply is connected to the negative terminal of reometer, and reometer just is being connected to the input end Ui of one three end adjustable series integrated package of pressure-stabilizing and an end of capacitor C 2; The output terminal U0 of three end adjustable series integrated package of pressure-stabilizing is connected to an end of resistance R 3; The other end of the other end of capacitor C 2, resistance R 3, and the adjustment end ADj ground connection of three end adjustable series integrated package of pressure-stabilizing.
The utility model direct supply load device has replaced the prior art pure resistor load, very low voltage is shared by the small resistor value, overwhelming majority voltage drop drops on high power valve and the adjustable integrated package of pressure-stabilizing of three ends, utilize adjustment member, sampling part, comparison amplifier section, the reference voltage of the adjustable integrated regulator of three ends partly to solve the problem that power source loads oven temperature, liter is too high, influence the power supply test precision, therefore, it is little to have obtained temperature rise, the little beneficial effect that waits of the electric current drift amount that works long hours.
The utility model can be applicable in the load device of various similar direct supply debugging usefulness.
Description of drawings
Fig. 1 is the electrical schematic diagram of a kind of dc positive power load device of the utility model;
Fig. 2 is the electrical schematic diagram of a kind of dc negative supply load device of the utility model.
Embodiment
Below in conjunction with description of drawings preferred embodiment of the present utility model.
Fig. 1 represents embodiment one of the present utility model; A kind of electrical schematic diagram of dc positive power load device; Shown in the embodiment of Fig. 1, the output terminal of positive 12V power supply is connected to the anode of 5A reometer, and the reometer negative terminal is with the emitter of resistance R 1, large power triode V1, and an end of capacitor C 1 connects; The other end of resistance R 1 is connected with the base stage of large power triode V1 and the input end Ui of three end adjustable series integrated package of pressure-stabilizing LM317; The collector of large power triode V1 is connected with resistance R 2 with the output terminal U0 of integrated package LM317; The adjustment end ADj ground connection of the other end of the other end of capacitor C 1, resistance R 2 and LM317 integrated package.Above-mentioned each components and parts have formed+load of 12V power supply.
The principle of work that now aligns the 12V power load circuit is described below:
LM317 makes that LM317 output terminal U0 is 1.2V after adjusting end ADJ ground connection, because the R2 both end voltage is 1.2V, and electric current is 3.5A, and then the R2 resistance is 1.2/3.5=0.343 (Ω).Because electric current is 3.5A, substantially exceeded the 1.5A limiting current of integrated package LM317, therefore, adopt large power triode V1 that LM317 is expanded stream, because the Vbe=0.6V of large power triode V1, if flow through the LM317 electric current is 0.5A, and then the R1 resistance is 0.6/0.5=1.2 (Ω), and the 3A electric current is then shared by the V1 high power valve.The effect of capacitor C 1 is to eliminate the circuit self-excitation.
Fig. 2 represents embodiment two of the present utility model, a kind of electrical schematic diagram of dc negative supply load device, shown in the embodiment of Fig. 2, the output of negative 12V power supply is connected to the negative terminal of 500mA reometer, and reometer just is being connected to the input end Ui of three end adjustable series integrated package of pressure-stabilizing LM337 and an end of capacitor C 2; Chip output U0 is connected to an end of resistance R 3; The other end of the other end of capacitor C 2, resistance R 3, and the adjustment end ADj ground connection of integrated package LM337.Above-mentioned each components and parts have formed-load of 12V power supply.
Now the principle of work to negative 12V direct supply load circuit is described below:
LM337 adjusts end ADj ground connection, makes the voltage of output terminal U0 be-1.2V, because-the 12V working current is-300mA, so the value of resistance R 3 is-1.2/-0.3=4 (Ω).Above-mentioned capacitor C 2 is established for eliminating the circuit self-excitation.
Shown in the embodiment of Fig. 1 and Fig. 2, in the power source loads device of the present utility model:
It is that 200W, breakdown reverse voltage are that 200V, maximum current are the 2SA1494 of 20A that large power triode V1 has selected power for use, and+the 12V real work is the 3A electric current, meets design of Reducing Rating.
LM317/LM337 input end, output end voltage difference be less than 40V, maximum current 1.5A, and real work input end, output end voltage difference are all less than 12V, and working current is respectively 0.5A, 0.3A, also meets design of Reducing Rating.
+ 12V sample resistance R2 is 1.2/3.5=0.343 (Ω), and power consumption is 1.2 * 3.5=4.2 (W) on the resistance, select for use 3 Ω 2W totally 8 resistance parallel connections to add some resistance more in parallel and obtain, so power greater than 16W much larger than 4.2W.
-12V sample resistance R3 is 1.2/0.3=4 (Ω), and power is 0.36W, select for use 1 Ω 2W totally 4 the series connection power be that 8W is much larger than 0.36W.The elite oxidized metal film resistance of using of sample resistance, this temperature-coefficient of electrical resistance is minimum.
High power valve is installed in earlier on 309mm * 100mm * 76mm (length * height * wide) heating radiator, is installed in cabinet then behind, is enough to provide the heat of the above power of 50W to be dispersed.
Test and result thereof
The model machine of this load device is through test more than 100 hours, every index all meets the specification, the heating radiator temperature rise is less than 30 ℃, electric current drift amount is 1 ‰ in the+12V load 8 hours, electric current drift amount is 1% in the-12V load 8 hours, and+12V by+4.5V～+ 30V ,-12V by-4.5V～-30V, it is constant still to keep drift, therefore thinks and invents successfully.
Attached: 8 hours working current contrast tables
| The requirement of answering machine output current | Former ohmic load case load current (A) | Existing electronic load box load current (A) |
| +12±0.2V(3.5A±5％) | 3.210～3.610 | 3.505～3.499 |
| -12±0.2V(0.3A±5％) | 0.280～0.330 | 0.302～0.298 |
Therefore the utility model direct supply load device has quoted that the principle of constant current source realizes.Complete constant-current source circuit comprises adjustment member, sampling part, comparison amplifier section, reference voltage part.And the basic circuit of the adjustable integrated regulator LM317/LM337 of three ends inside has contained generally adjustment member, sampling part, comparison amplifier section, reference voltage part.Its function is achieved like this: output voltage is distributed, very little voltage is shared by the small resistor value, overwhelming majority voltage drop drops on high power valve and the integrated package, because power tube and integrated package are mounted on 309mm * 100mm * 76mm (length * wide * height) heating radiator, so its power consumption produces heat and just can distribute smoothly, temperature reduces greatly in the cabinet.Because integrated package contains adjustment member, sampling part, comparison amplifier section, reference part, so guaranteed that the voltage on the small resistor value is constant all the time, has obtained the constant current purpose, has improved the testing current precision.
The performance of above-mentioned three end adjustable series integrated regulator LM317/LM337 is very good.They can be adjustable continuously in the scope of 1.2～37V, and exportable 1.5A load current.This integrated regulator chip internal also is provided with overcurrent, and so overheated and adjustment pipe safety operation area holding circuit is safe and reliable.
Claims (5)
1. the load device of a dc positive power is characterized in that, this device comprises: the output terminal of positive direct-current power supply is connected to the anode of reometer; The negative terminal of reometer connects with emitter, the capacitor C 1 of resistance R 1, large power triode V1; The other end of resistance R 1 is connected with the base stage of large power triode V1 and the input end Ui of three end adjustable series integrated package of pressure-stabilizing; The collector of large power triode V1 is connected with resistance R 2 with the output terminal U0 of three end adjustable series integrated package of pressure-stabilizing; The other end of the other end of capacitor C 1, resistance R 2, and the adjustment end ADj ground connection of three end adjustable series integrated package of pressure-stabilizing.
2. the load device of dc positive power according to claim 1, it is characterized in that: described three end adjustable series integrated package of pressure-stabilizing are LM317.
3. the load device of dc positive power according to claim 1, it is characterized in that: the power of described large power triode V1 is that 200W, breakdown reverse voltage are that 200V, maximum current are 20A.
4. the load device of a dc negative supply is characterized in that, this device comprises: the output of negative direct supply is connected to the negative terminal of reometer, and reometer just is being connected to the input end Ui of one three end adjustable series integrated package of pressure-stabilizing and an end of capacitor C 2; The output terminal U0 of three end adjustable series integrated package of pressure-stabilizing connects with resistance R 3; The other end of the other end of capacitor C 2, resistance R 3, and the adjustment end ADj ground connection of three end adjustable series integrated package of pressure-stabilizing.
5. dc negative supply load device according to claim 4 is characterized in that: described three end adjustable series integrated package of pressure-stabilizing are LM337.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200720073679 CN201069451Y (en) | 2007-08-16 | 2007-08-16 | DC power load device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200720073679 CN201069451Y (en) | 2007-08-16 | 2007-08-16 | DC power load device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201069451Y true CN201069451Y (en) | 2008-06-04 |
Family
ID=39490840
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200720073679 Expired - Fee Related CN201069451Y (en) | 2007-08-16 | 2007-08-16 | DC power load device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201069451Y (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102025139A (en) * | 2010-11-11 | 2011-04-20 | 苏州合欣美电子科技有限公司 | Current expanding and limiting protection circuit of ecological house |
| CN109343630A (en) * | 2018-11-28 | 2019-02-15 | 中国科学院西安光学精密机械研究所 | Voltage stabilizing circuit and design method thereof with SINK current capability and positive voltage output |
-
2007
- 2007-08-16 CN CN 200720073679 patent/CN201069451Y/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102025139A (en) * | 2010-11-11 | 2011-04-20 | 苏州合欣美电子科技有限公司 | Current expanding and limiting protection circuit of ecological house |
| CN109343630A (en) * | 2018-11-28 | 2019-02-15 | 中国科学院西安光学精密机械研究所 | Voltage stabilizing circuit and design method thereof with SINK current capability and positive voltage output |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN211123821U (en) | Linear voltage stabilizing circuit applied to ammeter and terminal | |
| CN201069451Y (en) | DC power load device | |
| CN103701341A (en) | Voltage following type depth negative feedback constant current source device | |
| CN103049029B (en) | Current-limiting circuit | |
| CN103312166A (en) | Power management circuit and electronic device | |
| CN108462031B (en) | Semiconductor laser adjustable constant current drive circuit based on NTC type resistance | |
| CN204145296U (en) | A kind of DC numerical control power supply | |
| CN107591282B (en) | Control device and method for relay coil | |
| CN101436756A (en) | Drive device for power supply of high power semiconductor laser device | |
| CN203405750U (en) | Voltage stabilizing circuit and voltage stabilizing power supply device | |
| CN202261002U (en) | Conduction control circuit with dummy load resistor inside direct-current power supply | |
| CN101436755B (en) | Drive device for power supply of low power semiconductor laser device | |
| CN204576330U (en) | A kind of constant-current source circuit | |
| CN202524600U (en) | Buck LED constant current drive control circuit | |
| CN115528764A (en) | Over-temperature protection circuit | |
| CN201788202U (en) | Electronic load circuit | |
| CN209134294U (en) | A kind of started with high voltage and constant current circuit with temperature-compensating | |
| CN206542330U (en) | A kind of auto-excitation type Buck converters based on controllable accurate source of stable pressure | |
| CN204835485U (en) | Excess temperature protection circuit of UPS charger | |
| CN103580460B (en) | Power supply change-over device | |
| CN102013804B (en) | Method for compensating large-current output voltage accuracy of switching power supply in wide temperature range | |
| CN217133336U (en) | Booster DC-DC converter testing device capable of expanding power | |
| CN201638099U (en) | Controllable high-accuracy constant-current source structure adopting constant-current diode with control end | |
| CN102954022B (en) | Fan control circuit | |
| CN109947162A (en) | Adjustable Voltage stabilizing module current-amplifying device |
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: 20080604 Termination date: 20110816 |