CN218386839U - Charging circuit for improving boost DC-DC - Google Patents
Charging circuit for improving boost DC-DC Download PDFInfo
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- CN218386839U CN218386839U CN202221590398.5U CN202221590398U CN218386839U CN 218386839 U CN218386839 U CN 218386839U CN 202221590398 U CN202221590398 U CN 202221590398U CN 218386839 U CN218386839 U CN 218386839U
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Abstract
The utility model belongs to the technical field of the lithium cell, a improve charging circuit who steps up DC-DC is disclosed. The charging circuit comprises a boost conversion circuit, a constant current control circuit and a DC-DC voltage feedback circuit, wherein the boost conversion circuit is respectively connected with the constant current control circuit and the DC-DC voltage feedback circuit. The utility model discloses be used for solving in the current lithium cell application product many separately to charge management and control and lithium electricity protection, so just need increase one in addition and charge the management and control, the problem that the circuit becomes complicated.
Description
Technical Field
The utility model belongs to the technical field of the lithium cell, concretely relates to improve charging circuit who steps up DC-DC.
Background
In the lithium battery charging process, due to the characteristic requirements of a lithium battery cell, a circuit firstly has constant current and then has constant voltage, the charging is turned off after full charge, and the two full charge conditions, namely a full charge voltage value and a cut-off current value, exist. The cost of implementing these charge management circuits is still high and there are few boost-type lithium battery charging ICs. In order to reduce cost and meet the lithium battery charging condition, a perfect combination of a lithium battery protection IC and a DCDC circuit needs to be found. At present, each user house has a plurality of 5V adapters, and if the boost DCDC can be well applied to lithium charging, the 5V adapters can be well utilized.
SUMMERY OF THE UTILITY MODEL
The utility model provides an improve DC-DC's charging circuit that steps up for solve in the current lithium cell application product many separately to the management and control and the lithium electricity protection of charging, so just need increase another management and control of charging, the problem that the circuit becomes complicated.
The utility model discloses a following technical scheme realizes:
a charging circuit for improving boosting DC-DC comprises an input interface J1, a capacitor C6, a chip U1, an inductor L1, a resistor R5, a diode D2, a capacitor C1 and a capacitor C2, wherein the end 1 of the input interface J1 is respectively connected with one end of the capacitor C6, the end 5 of the chip U1 and one end of the inductor L1, the other end of the inductor L1 is respectively connected with the anode of the diode D2 and the end 1 of the chip U1, the end 2 of the input interface J1 is respectively connected with the other end of the capacitor C6 and a grounding end, the end 4 of the chip U1 is respectively connected with one end of the resistor R5 and one end of the resistor R10, and the other end of the resistor R5 is grounded;
the cathode of the diode D2 is respectively connected with one end of the capacitor C1, one end of the capacitor C2, one end of the resistor R4, the e end of the triode Q1 and the anode of the diode D1,
the No. 3 end of the chip U1 is respectively connected with one end of a resistor R7, the other end of the resistor R4, the C end of the triode Q1 and one end of a capacitor C4, the No. 3 end of the chip U1 is respectively connected with the other end of the resistor R7 and a grounding end,
the other end of the resistor R2 is respectively connected with the end b of the triode Q1 and one end of the resistor R6, the other end of the resistor R6 is respectively connected with the other end of the capacitor C4 and the end C of the triode Q2, the end b of the triode Q2 is connected with one end of the resistor R8, and the end e of the triode Q2 is respectively connected with one end of the resistor R11 and the grounding end;
the other end of the resistor R8 is connected with one end of a resistor R9 and the anode of the diode D3 respectively, and the other end of the resistor R9 is connected with the end of the network identification Vin; the other end of the resistor R11 is respectively connected with the cathode of the diode D3, the terminal B-of the network identifier, the terminal No. 3 of the battery pack P1, one end of the capacitor C5 and the VSS end of the chip U2;
the cathode of the diode D1 is respectively connected with the terminal B + of the network identifier, one end of the resistor R1 and the terminal No. 1 of the battery pack P1; the other end of the resistor R1 is connected with one end of a capacitor C3 and the VC1 end of the chip U2 respectively, the other end of the capacitor C3 is connected with the other end of a capacitor C5, one end of the resistor R3 and the VC2 end of the chip U2 respectively, and the other end of the resistor R3 is connected with the intermediate voltage VC end of the battery pack and the No. 3 end of the battery pack P1 respectively;
and the CO end of the chip U2 is connected with the other end of the resistor R10.
A charging circuit for improving boost DC-DC comprises a boost conversion circuit, a constant current control circuit and a DC-DC voltage feedback circuit, wherein the boost conversion circuit is respectively connected with the constant current control circuit and the DC-DC voltage feedback circuit;
the boost conversion circuit comprises a chip U1, an inductor L1 and a diode D2 and boosts input voltage;
the DC-DC voltage feedback circuit comprises a resistor R4 and a resistor R7 and is used for charging the lithium battery at a constant voltage;
the constant current control circuit comprises a resistor R11, a diode D3, a triode Q1 and a triode Q2 and is used for constant current charging of the lithium battery.
A charging circuit for improving boosting DC-DC is characterized in that a battery pack is formed by connecting a single string of batteries or a plurality of strings of batteries in series.
A charging circuit of a diode D capacitor C of a boost diode D capacitor C is characterized in that a No. 1 end of an input interface J1 of the charging circuit is connected with a No. 5 end and a network identification Vin of a chip U1, a No. 2 end of the input interface J1 is connected with an SGND, a capacitor C6 is connected between the network identification Vin and the SGND2, a capacitor L1 is connected between the No. 5 end and the No. 1 end of the chip U1, the No. 1 end of the L1 is connected with an A end of the diode D2, a K end of the diode D2 is connected with a capacitor C1+ end, the network identification is Vout, the capacitor C2 is connected between the network identification Vout and the SGND1, the K end of the diode D1 is connected with an anode of a battery pack P1, the network identification is B +, a cathode of the battery pack is connected with a No. 3 end of the chip U2, the network identification is B-, a middle pole V capacitor C of the battery pack P1 is connected with the No. 2 end of the chip U2 through a resistor R3, and the network identification B + is connected with the No. 1 end of the chip U2 through a resistor R1, capacitor C3 connects between chip U2's end No. 1 and end No. 2, capacitor C5 connects between chip U2's end No. 2 and end No. 3, chip U2's end No. 9 connects to chip U1's end No. 4 through resistance R10, resistance R5 connects between chip U1's end No. 4 and SGND, resistance R11 connects between B-and SGND, diode D3's K connects network identification B-, diode D3's A terminates resistance R9, resistance R9 connects network identification Vin, diode D3's A connects triode Q2's end B through resistance R8, triode Q2's capacitor C connects triode Q1's end B through resistance R6, triode Q1's capacitor C/e connects to resistance R4's both ends, resistance R2 connects between triode Q1's end B/e, capacitor C4 connects between triode Q1's capacitor C and triode Q2's capacitor C, resistance R7 connects between chip U1's end No. 3 and SGND, resistance R4 connects chip U1's end No. 3 and Vout.
The model of the chip U1 is RY3715, and the model of the chip U2 is CM1022-BA.
The model of the chip U1 can be replaced by other DCDC boosting models, and the model of the chip U2 can be replaced by other lithium battery protection ICs.
The utility model has the advantages that:
the utility model discloses a current negative feedback network realizes charging the lithium electricity constant current.
The utility model discloses upgrade DCDC's application in the lithium electricity product that steps up.
The utility model discloses by the change of diode D1 internal resistance, control cutoff current value changes the Vout value when the design and can change cutoff current value.
The utility model discloses the realization is to lithium electricity constant voltage charging.
The utility model discloses the realization is to lithium electricity constant current charging.
The utility model discloses the circuit composition is simple, and it is simple to revise according to actual scene, and the cost is very low, has good economic nature.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
A charging circuit for improving boosting DC-DC comprises an input interface J1, a capacitor C6, a chip U1, an inductor L1, a resistor R5, a diode D2, a capacitor C1 and a capacitor C2, wherein the end 1 of the input interface J1 is respectively connected with one end of the capacitor C6, the end 5 of the chip U1 and one end of the inductor L1, the other end of the inductor L1 is respectively connected with the anode of the diode D2 and the end 1 of the chip U1, the end 2 of the input interface J1 is respectively connected with the other end of the capacitor C6 and a grounding end, the end 4 of the chip U1 is respectively connected with one end of the resistor R5 and one end of the resistor R10, and the other end of the resistor R5 is grounded;
the cathode of the diode D2 is respectively connected with one end of the capacitor C1, one end of the capacitor C2, one end of the resistor R4, the e end of the triode Q1 and the anode of the diode D1,
the end 3 of the chip U1 is respectively connected with one end of the resistor R7, the other end of the resistor R4, the end C of the triode Q1 and one end of the capacitor C4, the end 3 of the chip U1 is respectively connected with the other end of the resistor R7 and the grounding end,
the other end of the resistor R2 is respectively connected with the b end of a triode transistor Q1 and one end of a resistor R6, the other end of the resistor R6 is respectively connected with the other end of a capacitor C4 and the C end of the triode Q2, the b end of the triode Q2 is connected with one end of a resistor R8, and the e end of the triode Q2 is respectively connected with one end of a resistor R11 and a grounding end;
the other end of the resistor R8 is connected with one end of a resistor R9 and the anode of the diode D3 respectively, and the other end of the resistor R9 is connected with the end of the network identification Vin; the other end of the resistor R11 is connected with the cathode of the diode D3, the network identifier B-end, the No. 3 end of the battery pack P1, one end of the capacitor C5 and the VSS end of the chip U2 respectively;
the cathode of the diode D1 is connected with the terminal B + of the network identifier, one end of the resistor R1 and the terminal No. 1 of the battery pack P1 respectively; the other end of the resistor R1 is connected with one end of a capacitor C3 and the VC1 end of the chip U2 respectively, the other end of the capacitor C3 is connected with the other end of a capacitor C5, one end of the resistor R3 and the VC2 end of the chip U2 respectively, and the other end of the resistor R3 is connected with the intermediate voltage VC end of the battery pack and the No. 3 end of the battery pack P1 respectively;
and the CO end of the chip U2 is connected with the other end of the resistor R10.
A charging circuit for improving boosting DC-DC comprises a boosting conversion circuit, a constant current control circuit and a DC-DC voltage feedback circuit, wherein the boosting conversion circuit is respectively connected with the constant current control circuit and the DC-DC voltage feedback circuit;
the boost conversion circuit comprises a chip U1, an inductor L1 and a diode D2, and boosts the input voltage;
the DC-DC voltage feedback circuit comprises a resistor R4 and a resistor R7 and is used for charging the lithium battery at a constant voltage;
the constant current control circuit comprises a resistor R11, a diode D3, a triode Q1 and a triode Q2 and is used for constant current charging of the lithium battery.
A charging circuit for improving boosting DC-DC is disclosed, wherein the lithium battery pack is a single-string battery or a plurality of strings of batteries connected in series.
A charging circuit of a diode D capacitor C of a boost diode D capacitor C is characterized in that a No. 1 end of an input interface J1 of the charging circuit is connected with a No. 5 end and a network identification Vin of a chip U1, a No. 2 end of the input interface J1 is connected with an SGND, a capacitor C6 is connected between the network identification Vin and the SGND2, a capacitor L1 is connected between the No. 5 end and the No. 1 end of the chip U1, the No. 1 end of the L1 is connected with an A end of the diode D2, a K end of the diode D2 is connected with a capacitor C1+ end, the network identification is Vout, the capacitor C2 is connected between the network identification Vout and the SGND1, the K end of the diode D1 is connected with an anode of a battery pack P1, the network identification is B +, a cathode of the battery pack is connected with a No. 3 end of the chip U2, the network identification is B-, a middle pole V capacitor C of the battery pack P1 is connected with the No. 2 end of the chip U2 through a resistor R3, and the network identification B + is connected with the No. 1 end of the chip U2 through a resistor R1, capacitor C3 connects between chip U2's end No. 1 and end No. 2, capacitor C5 connects between chip U2's end No. 2 and end No. 3, chip U2's end No. 9 connects to chip U1's end No. 4 through resistance R10, resistance R5 connects between chip U1's end No. 4 and SGND, resistance R11 connects between B-and SGND, diode D3's K connects network identification B-, diode D3's A terminates resistance R9, resistance R9 connects network identification Vin, diode D3's A connects triode Q2's end B through resistance R8, triode Q2's capacitor C connects triode Q1's end B through resistance R6, triode Q1's capacitor C/e connects to resistance R4's both ends, resistance R2 connects between triode Q1's end B/e, capacitor C4 connects between triode Q1's capacitor C and triode Q2's capacitor C, resistance R7 connects between chip U1's end No. 3 and SGND, resistance R4 connects chip U1's end No. 3 and Vout.
The model of the chip U1 is RY3715, and the model of the chip U2 is CM1022-BA.
The model of the chip U1 can be replaced by other DCDC boosting models, and the model of the chip U2 can be replaced by other lithium battery protection ICs.
The 5V adapter is connected from J1, and the capacitor C6 filters. The chips U1 and L1 and the diode D2 form the main device of the boost conversion circuit, and the voltage is increased from 5V to Vout. Vout charges the lithium battery pack through a diode D1, and P1 is connected with 2 strings of battery packs. The chip U2 is a 2-string lithium battery protection I capacitor C, the voltage of each cell is detected, and when the voltage of the single cell is charged to 4.225V, the capacitor CO is at a low level, and the charging is turned off. Wherein: the resistor R4 and the resistor R7 are DC-DC voltage feedback, and the Vout is stabilized at 8.75V during constant voltage; the resistor R11 is a current detection resistor, when the voltage on the resistor R11 plus the voltage drop of the diode D3 exceeds the conduction threshold value of the triode Q2, the triode Q1 also enters an amplification state, the equivalent resistance values at two ends of the resistor R4 become small, and the DC-DC enters a 1A constant current mode; the diode D1 achieves the full-electricity judgment effect, in the later charging period, the DC-DC is in a constant-voltage state, vout =8.75V, when the network identification B + is increased to 8.45V, the chip U2 acts, the capacitor CO is low, the DC-DC is turned off, the voltage drop of the diode D1 is 0.3V, the internal resistance is 4ohm, and the cut-off current value =75mA.
The working process is as follows: at the initial charging stage, the network identifier B + is low, the voltage drop generated by the current of the resistor R11 and the voltage drop of the diode D3 exceed or are close to the threshold value of the triode Q2, the triode Q2 and the triode Q1 are both in an amplification state, the equivalent resistance values at two ends of the resistor R4 are reduced, the PWM duty ratio of the DC-DC is controlled, and the constant current state is achieved, for example, the constant current state is controlled to be 1A. At this time, the diode D1 passes a large current, such as 1A, and the internal resistance becomes small, such as 0.4ohm, vout =0.4v + network flag B +. In the middle charging period, the network identifier B + is increased, when Vout =8.75V is reached, the voltage drop generated by the current of the resistor R11 plus the voltage drop of the diode D3 is smaller than the threshold value of the transistor Q2, the transistors Q2 and Q1 are both in a cut-off state, the DC-DC enters a constant voltage state, and the Vout value is determined by the resistor R4 and the resistor R7. When the charging is finished, when the network identifier B + rises to 8.45V, the voltage drop of the diode D1 is 0.3V, the internal resistance is 4ohm, the current value =75mA, the chip U2 is turned off, the capacitor CO is low, and the cutoff current value is 75mA.
Claims (6)
1. The charging circuit is characterized by comprising a boost conversion circuit, a constant current control circuit and a DC-DC voltage feedback circuit, wherein the boost conversion circuit is respectively connected with the constant current control circuit and the DC-DC voltage feedback circuit;
the boost conversion circuit comprises a chip U1, an inductor L1 and a diode D2, and boosts the input voltage;
the DC-DC voltage feedback circuit comprises a resistor R4 and a resistor R7 and is used for charging the lithium battery at a constant voltage;
the constant current control circuit comprises a resistor R11, a diode D3, a triode Q1 and a triode Q2 and is used for constant current charging of the lithium battery.
2. The charging circuit for improving boost DC-DC according to claim 1, wherein the charging circuit comprises an input interface J1, a capacitor C6, a chip U1, an inductor L1, a resistor R5, a diode D2, a capacitor C1 and a capacitor C2, wherein the terminal 1 of the input interface J1 is respectively connected with one end of the capacitor C6, the terminal 5 of the chip U1 and one end of the inductor L1, the other end of the inductor L1 is respectively connected with the anode of the diode D2 and the terminal 1 of the chip U1, the terminal 2 of the input interface J1 is respectively connected with the other end of the capacitor C6 and a ground terminal, the terminal 4 of the chip U1 is respectively connected with one end of the resistor R5 and one end of the resistor R10, and the other end of the resistor R5 is grounded;
the cathode of the diode D2 is respectively connected with one end of the capacitor C1, one end of the capacitor C2, one end of the resistor R4, the e end of the triode Q1 and the anode of the diode D1;
the end 3 of the chip U1 is respectively connected with one end of the resistor R7, the other end of the resistor R4, the end C of the triode Q1 and one end of the capacitor C4, and the end 2 of the chip U1 is respectively connected with the other end of the resistor R7 and the grounding end;
the other end of the resistor R2 is respectively connected with the end b of the triode Q1 and one end of the resistor R6, the other end of the resistor R6 is respectively connected with the other end of the capacitor C4 and the end C of the triode Q2, the end b of the triode Q2 is connected with one end of the resistor R8, and the end e of the triode Q2 is respectively connected with one end of the resistor R11 and the grounding end;
the other end of the resistor R8 is respectively connected with one end of a resistor R9 and the anode of the diode D3, and the other end of the resistor R9 is connected with the end of the network identifier Vin; the other end of the resistor R11 is connected with the cathode of the diode D3, the network identifier B-end, the No. 3 end of the battery pack P1, one end of the capacitor C5 and the VSS end of the chip U2 respectively;
the cathode of the diode D1 is respectively connected with the terminal B + of the network identifier, one end of the resistor R1 and the terminal No. 1 of the battery pack P1; the other end of the resistor R1 is connected with one end of a capacitor C3 and the VC1 end of the chip U2 respectively, the other end of the capacitor C3 is connected with the other end of a capacitor C5, one end of the resistor R3 and the VC2 end of the chip U2 respectively, and the other end of the resistor R3 is connected with the intermediate voltage VC end of the battery pack and the No. 3 end of the battery pack P1 respectively;
and the CO end of the chip U2 is connected with the other end of the resistor R10.
3. A charging circuit for improving boost DC-DC according to claim 2, characterized in that said battery pack is a single string of batteries or a series of strings of batteries.
4. A boost DC-DC charging circuit according to claim 1, the No. 1 end of an input interface J1 of the charging circuit is connected with the No. 5 end of a chip U1 and a network identifier Vin, the No. 2 end of the input interface J1 is connected with an SGND, a capacitor C6 is connected between the network identifier Vin and the SGND2, a capacitor L1 is connected between the No. 5 end and the No. 1 end of the chip U1, the No. 1 end of the L1 is connected with the A end of a diode D2, the K end of the diode D2 is connected with the C1+ end of a capacitor, the network identifier is Vout, the capacitor C2 is connected between the network identifier Vout and the SGND1, the K end of the diode D1 is connected with the anode of a battery pack P1, the network identifier is B +, the cathode of the battery pack is connected with the No. 3 end of the chip U2, the network identifier is B-, a middle pole V of the battery pack P1 is connected with the No. 2 end of the chip U2 through a resistor R3, the network identifier B + is connected with the No. 1 end of the chip U2 through a resistor R1, and the capacitor C3 is connected between the No. 1 end and the No. 2 end of the No. 2 of the chip U2, the capacitor C5 is connected between the end No. 2 and the end No. 3 of the chip U2, the end No. 9 of the chip U2 is connected to the end No. 4 of the chip U1 through a resistor R10, the resistor R5 is connected between the end No. 4 of the chip U1 and the SGND, the resistor R11 is connected between B-and the SGND, the K of the diode D3 is connected with the network identifier B-, the A of the diode D3 is connected with the resistor R9, the resistor R9 is connected with the network identifier Vin, the A of the diode D3 is connected with the B end of the triode Q2 through a resistor R8, the capacitor C of the triode Q2 is connected with the B end of the triode Q1 through a resistor R6, the capacitor C/e of the triode Q1 is connected to the two ends of the resistor R4, the resistor R2 is connected between the B/e of the triode Q1, the capacitor C4 is connected between the capacitor C of the triode Q1 and the capacitor C of the triode Q2, the resistor R7 is connected between the end No. 3 of the end of the chip U1 and the SGND, and the resistor R4 is connected with the end No. 3 of the end of the chip U1 and the network identifier Vout.
5. The charging circuit for improving boost DC-DC of claim 2, wherein the model of said chip U1 is RY3715, and the model of said chip U2 is CM1022-BA.
6. The charging circuit for improving boost DC-DC according to claim 5, wherein the model of the chip U1 can be replaced by a DCDC boost model, and the model of the chip U2 can be replaced by a lithium battery protection IC.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221590398.5U CN218386839U (en) | 2022-06-23 | 2022-06-23 | Charging circuit for improving boost DC-DC |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221590398.5U CN218386839U (en) | 2022-06-23 | 2022-06-23 | Charging circuit for improving boost DC-DC |
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| Publication Number | Publication Date |
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| CN218386839U true CN218386839U (en) | 2023-01-24 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202221590398.5U Active CN218386839U (en) | 2022-06-23 | 2022-06-23 | Charging circuit for improving boost DC-DC |
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| Country | Link |
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| CN (1) | CN218386839U (en) |
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2022
- 2022-06-23 CN CN202221590398.5U patent/CN218386839U/en active Active
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