CN219760655U - DCDC circuit for realizing constant current and constant voltage - Google Patents
DCDC circuit for realizing constant current and constant voltage Download PDFInfo
- Publication number
- CN219760655U CN219760655U CN202223487308.2U CN202223487308U CN219760655U CN 219760655 U CN219760655 U CN 219760655U CN 202223487308 U CN202223487308 U CN 202223487308U CN 219760655 U CN219760655 U CN 219760655U
- Authority
- CN
- China
- Prior art keywords
- dcdc
- voltage
- feedback module
- current
- constant
- 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.)
- Active
Links
- HEZMWWAKWCSUCB-PHDIDXHHSA-N (3R,4R)-3,4-dihydroxycyclohexa-1,5-diene-1-carboxylic acid Chemical compound O[C@@H]1C=CC(C(O)=O)=C[C@H]1O HEZMWWAKWCSUCB-PHDIDXHHSA-N 0.000 title claims abstract description 45
- 239000003990 capacitor Substances 0.000 claims description 22
- 238000002955 isolation Methods 0.000 claims description 9
- 238000001914 filtration Methods 0.000 claims description 6
- 238000005070 sampling Methods 0.000 claims description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000007600 charging Methods 0.000 description 5
- 101001074602 Homo sapiens Protein PIMREG Proteins 0.000 description 1
- 102100036258 Protein PIMREG Human genes 0.000 description 1
- 238000010280 constant potential charging Methods 0.000 description 1
- 238000010277 constant-current charging Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
Abstract
The utility model provides a DCDC circuit for realizing constant current and constant voltage, which comprises an output end, a DCDC chip, a voltage feedback module and a current feedback module, wherein the voltage feedback module is connected with the output end and a feedback pin of the DCDC chip; one end of the current feedback module is connected with the output end and the battery to be charged, and the other end of the current feedback module is connected with the DCDC feedback pin. When the battery to be charged is low in voltage, constant-current power supply can be realized, and when the battery reaches a constant voltage value, constant-voltage power supply can be performed, so that compared with a constant-current constant-voltage circuit controlled by an MCU, the utility model saves cost and is beneficial to market popularization.
Description
Technical Field
The utility model relates to the technical field of circuits, in particular to a DCDC circuit for realizing constant current and constant voltage.
Background
For the PACK of small household appliances in the current market, most of the used chargers adopt a constant voltage output mode, but the charging current is not constant, and in the normal case, when the voltage of the PACK is lower, the charging current is larger, and when the voltage of the PACK is higher, the charging current is smaller.
In order to realize the constant-current and constant-voltage output of the charging module, the MCU is added for control, and the MCU is used for logic judgment to realize the switching of the constant-current and constant-voltage charging mode, so that the charging module has higher cost compared with a common non-constant-current charger, and is not beneficial to large-scale popularization and use.
Disclosure of Invention
In order to solve the problems, the utility model provides a DCDC circuit for realizing constant current and constant voltage.
The main content of the utility model comprises:
a DCDC circuit for implementing constant current followed by constant voltage, comprising: the device comprises an output end, a DCDC chip, a voltage feedback module and a current feedback module, wherein the voltage feedback module is connected with the output end and a feedback pin of the DCDC chip; one end of the current feedback module is connected with the output end and the battery to be charged, and the other end of the current feedback module is connected with a feedback pin of the DCDC chip.
Preferably, the current feedback module comprises a current sampling resistor connected with a negative interface of the output end, an operational amplifier and an isolation diode, wherein a positive input end of the operational amplifier is connected with the negative interface of the output end, a reverse input end of the operational amplifier is connected with a negative discharge end of the battery to be charged through a first resistor, an output end of the operational amplifier is connected with an anode of the isolation diode, and a cathode of the isolation diode is connected with a feedback pin of the DCDC chip.
Preferably, the current feedback module further comprises a second resistor and a first capacitor which are connected in parallel; the second resistor and the first capacitor are connected between the inverting input terminal and the output terminal of the operational amplifier.
Preferably, the voltage feedback module comprises a third resistor and a fourth resistor connected in series between the positive interface and the negative interface of the output end, and a feedback pin of the DCDC chip is connected between the third resistor and the fourth resistor.
Preferably, a filtering bootstrap branch circuit is further connected between the output pin of the DCDC chip and the positive interface of the output end, the filtering bootstrap branch circuit comprises a second capacitor and an inductor, one end of the second capacitor is connected with the bootstrap pin of the DCDC chip, the other end of the second capacitor is connected with one end of the inductor, and the output pin of the DCDC chip is connected between the second capacitor and the inductor; the other end of the inductor is connected with the positive interface of the output end and one end of a third capacitor, and the other end of the third capacitor is grounded.
The utility model has the beneficial effects that: the utility model provides a DCDC circuit for realizing constant current and then constant voltage, which realizes constant current power supply when the voltage of a battery to be charged is low, and can perform constant voltage power supply after the battery reaches a constant voltage value.
Drawings
Fig. 1 is a circuit diagram of the present utility model.
Detailed Description
The technical scheme protected by the utility model is specifically described below with reference to the accompanying drawings.
Referring to fig. 1, the present utility model proposes a DCDC circuit for realizing constant current followed by constant voltage, comprising: the device comprises an output end (VOUT+, VOUT-), a DCDC chip U1, a voltage feedback module and a current feedback module, wherein the voltage feedback module is connected with the output end and a feedback pin FB of the DCDC chip; the DCDC chip is used for acquiring an output voltage value and feeding the output voltage value back to the DCDC chip so as to regulate the output voltage; one end of the current feedback module is connected with the output end and the battery to be charged, and the other end of the current feedback module is connected with a feedback pin of the DCDC chip and is used for comparing the output voltage with the voltage of the battery to be charged, and when the voltage of the battery to be charged is smaller than the output voltage, the difference value is fed back to the DCDC chip so as to adjust the output voltage and realize constant current output; when the voltage of the rechargeable battery reaches a constant voltage value, the current feedback module does not feed back the difference value to the DCDC chip, and the DCDC chip only carries out constant voltage output according to the voltage feedback module.
Specifically, the current feedback module includes a current sampling resistor RCS1 connected to the negative interface VOUT-of the output end, an operational amplifier, and an isolation diode D6, where the positive input end+ of the operational amplifier is connected to the negative interface VOUT-of the output end, the negative input end-of the operational amplifier is connected to the negative discharge end P-of the battery to be charged through a first resistor R18, the output end of the operational amplifier is connected to the positive electrode of the isolation diode D6, and the negative electrode of the isolation diode D6 is connected to the feedback pin FB of the DCDC chip.
Further, the current feedback module further comprises a second resistor R19 and a first capacitor C5 which are connected in parallel; the second resistor R19 and the first capacitor C5 are connected between the inverting input of the operational amplifier and its output.
The voltage feedback module comprises a third resistor R3 and a fourth resistor R12 which are connected in series between a positive interface VOUT+ and a negative interface VOUT-of the output end, and a feedback pin FB of the DCDC chip is connected between the third resistor R3 and the fourth resistor R12.
In one embodiment, a filtering bootstrap branch is further connected between the output pin SW of the DCDC chip and the positive interface vout+ of the output end, the filtering bootstrap branch includes a second capacitor C1 and an inductor L1, one end of the second capacitor C1 is connected to the bootstrap pin BST of the DCDC chip, the other end is connected to one end of the inductor L1, and the output pin SW of the DCDC chip is connected between the second capacitor C1 and the inductor L1; the other end of the inductor L1 is connected with the positive interface VOUT+ of the output end and one end of a third capacitor C3, and the other end of the third capacitor C3 is grounded.
The foregoing description is only illustrative of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structures or equivalent processes or direct or indirect application in other related technical fields are included in the scope of the present utility model.
Claims (5)
1. A DCDC circuit for implementing constant current followed by constant voltage, comprising: the device comprises an output end, a DCDC chip, a voltage feedback module and a current feedback module, wherein the voltage feedback module is connected with the output end and a feedback pin of the DCDC chip; one end of the current feedback module is connected with the output end and the battery to be charged, and the other end of the current feedback module is connected with a feedback pin of the DCDC chip.
2. The DCDC circuit of claim 1, wherein the current feedback module includes a current sampling resistor connected to the negative interface of the output terminal, an operational amplifier, and an isolation diode, the positive input terminal of the operational amplifier is connected to the negative interface of the output terminal, the negative input terminal of the operational amplifier is connected to the negative discharge terminal of the battery to be charged through the first resistor, the output terminal of the operational amplifier is connected to the positive electrode of the isolation diode, and the negative electrode of the isolation diode is connected to the feedback pin of the DCDC chip.
3. The DCDC circuit of claim 2, wherein the current feedback module further comprises a second resistor and a first capacitor connected in parallel; the second resistor and the first capacitor are connected between the inverting input terminal and the output terminal of the operational amplifier.
4. The DCDC circuit of claim 1, wherein the voltage feedback module includes a third resistor and a fourth resistor connected in series between the positive interface and the negative interface of the output terminal, and the feedback pin of the DCDC chip is connected between the third resistor and the fourth resistor.
5. The DCDC circuit for implementing constant current followed by constant voltage according to claim 1, wherein a filtering bootstrap branch is further connected between an output pin of the DCDC chip and a positive interface of the output end, the filtering bootstrap branch includes a second capacitor and an inductor, one end of the second capacitor is connected with a bootstrap pin of the DCDC chip, the other end is connected with one end of the inductor, and the output pin of the DCDC chip is connected between the second capacitor and the inductor; the other end of the inductor is connected with the positive interface of the output end and one end of a third capacitor, and the other end of the third capacitor is grounded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223487308.2U CN219760655U (en) | 2022-12-25 | 2022-12-25 | DCDC circuit for realizing constant current and constant voltage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223487308.2U CN219760655U (en) | 2022-12-25 | 2022-12-25 | DCDC circuit for realizing constant current and constant voltage |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219760655U true CN219760655U (en) | 2023-09-26 |
Family
ID=88081445
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223487308.2U Active CN219760655U (en) | 2022-12-25 | 2022-12-25 | DCDC circuit for realizing constant current and constant voltage |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219760655U (en) |
-
2022
- 2022-12-25 CN CN202223487308.2U patent/CN219760655U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN208386212U (en) | A kind of uninterruptible power supply | |
| CN102629825A (en) | Circuit structure of realizing synchronous buck-type charging and boost-type power supply by using single inductor | |
| CN104767252A (en) | Tablet computer | |
| CN204615444U (en) | Panel computer | |
| CN203552117U (en) | MPPT (maximum power point tracking) solar controller | |
| CN102969783B (en) | Direct current uninterruptible power supply | |
| CN211456754U (en) | Portable power source of step-down output | |
| CN202931003U (en) | Battery charging circuit and power supply circuit | |
| CN219760655U (en) | DCDC circuit for realizing constant current and constant voltage | |
| CN201750171U (en) | Novel traveling emergency charger | |
| CN205377371U (en) | Lead acid battery undervoltage protection automatic control circuit | |
| CN206442169U (en) | Portable type solar recharging knapsack | |
| CN203261052U (en) | Charging circuit utilizing battery of turned-off laptop | |
| CN202737505U (en) | Boost charging circuit of storage battery | |
| CN201947182U (en) | Bi-directional DC/DC (direct current to direct current) power supply | |
| CN209200724U (en) | A kind of efficient charging circuit for the wide input power of model airplane battery | |
| CN201830141U (en) | DC-DC negative voltage conversion circuit | |
| CN202616999U (en) | Circuit configuration for realizing synchronous step-down charging and step-up power supply by using single inductor | |
| CN208675108U (en) | It is a kind of to be depressured the direct-current switch power supply conversion circuit that boosted | |
| CN201113475Y (en) | USB charger possessing control switch | |
| CN209526556U (en) | Power supply switch circuit | |
| CN111865077A (en) | Direct-current booster circuit applied to energy supply of relay protection device of transformer substation | |
| CN204809892U (en) | USB type portable power source | |
| CN104283245A (en) | High-conversion-efficiency mobile power source circuit | |
| CN204316114U (en) | Lithium battery multi-output power supply circuit in a kind of mobile terminal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |