Circuit for converting 1.8 VDC into 3.3 VDC

Abstract

The utility model relates to a circuit for converting 1.8 VDC into 3.3 VDC, which comprises a converter circuit, an isolation drive circuit connected with the converter circuit, and a rectifier bridge circuit, the circuit for converting 1.8 VDC into 3.3 VDC can convert 1.8 VDC into a 3VDC power supply, the 3.3 VDC power supply can be stably output to supply power to a post-stage circuit under the condition that 1.8 VDC is extremely low, and the circuit for converting 1.8 VDC into 3.3 VDC can be used for converting 3.3 VDC into 3.3 VDC. Therefore, the service life of the battery in the portable application is prolonged to a great extent, and the working stability of the circuit is ensured at the same time.

Description

Technical Field

[0001] The utility model belongs to the technical field of power supply circuits, and in particular relates to a circuit for converting 1.8VDC to 3.3VDC. Background Art

[0002] A DC power supply is a device that maintains a constant voltage and current in a circuit. Such as dry batteries, storage batteries, DC generators, etc. A DC power supply has two electrodes, positive and negative. The positive electrode has a high potential and the negative electrode has a low potential. When the two electrodes are connected to the circuit, a constant potential difference can be maintained between the two ends of the circuit, thereby forming a current from the positive electrode to the negative electrode in the external circuit. A DC power supply is an energy conversion device that converts other forms of energy into electrical energy to supply the circuit in order to maintain a constant flow of current.

[0003] Existing DC power supplies all convert high voltage power supplies such as 5VDC and 12VDC to achieve 3.3VDC DC power supply, and voltages lower than 3.3VDC are generally not applicable. Summary of the invention

[0004] In order to solve the problem that the existing DC power supply cannot stably use a voltage lower than 3.3VDC to form a stable 3.3VDC voltage to power electronic devices.

[0005] The utility model provides a circuit for converting 1.8VDC to 3.3VDC, comprising a circuit +input end and a circuit -input end, a capacitor C10 is arranged between the circuit +input end and the circuit -input end, the +input end is electrically connected to pin 3 of the converter, the circuit -input end is electrically connected to pin 2 of the converter, pin 1 of the converter is electrically connected to pin 3 of the converter, an inductor L3 is arranged between pin 3 of the converter and pin 6 of the converter, pin 5 of the converter is electrically connected to pin 2 of the isolation chip, pin 2 of the isolation chip is electrically connected to pin 3 of the isolation chip, pin 4 of the converter is electrically connected to pin 6 of the isolation chip, pin 6 of the isolation chip is electrically connected to pin 7 of the isolation chip, and pin 8 of the converter is electrically connected to pin 9 of the isolation chip. A capacitor C11 is arranged between pin 5 and pin 4 of the converter, a capacitor C12 is further arranged between pin 5 of the converter and pin 4 of the converter, the resistor R23 and the capacitor C13 are connected in parallel and arranged between pin 1 of the isolation chip and pin 6 of the isolation chip, the pin 8 of the isolation chip and the pin 5 of the isolation chip are electrically connected to the two input ends of the transformer TR1 respectively, the two output ends of the transformer TR1 are electrically connected to the two input ends of the rectifier bridge, one output end of the rectifier bridge is electrically connected to one end of the inductor L4, the other end of the inductor L4 is the circuit + output end, the other output end of the rectifier bridge is electrically connected to one end of the inductor L5, the other end of the inductor L5 is the circuit - output end, and a capacitor C14 is further arranged between the two output ends of the rectifier bridge.

[0006] Furthermore, the converter is a step-up DC / DC converter, and its model is LTC3525-3.3.

[0007] Furthermore, the isolation chip model is SGM46000.

[0008] Furthermore, the model of the rectifier bridge is KMB14F.

[0009] The 1.8VDC to 3.3VDC conversion circuit provided by the utility model has the following advantages: the circuit adopts a high-efficiency, synchronous boost DC / DC converter LTC3525-3.3 with an output disconnect function, and the device has a built-in 0.5Ω N-channel MOSFET switch and a 0.8Ω P-channel synchronous rectifier. It ensures that the internal power supply (battery) product stably outputs 3.3VDC power to power the subsequent circuit under the condition of extremely low input voltage (parallel state 1.8VDC), thereby greatly extending the battery life in portable applications and ensuring the stability of circuit operation.

[0010] At the same time, the subsequent circuit adds an isolation drive circuit to output the 3.3VDC voltage output by LTC3525 to the DC-DC isolation chip SGM46000. The isolation chip converts the DC voltage into an alternating signal with a switching frequency of about 150KHz through an internal oscillator, and restores it to the required DC voltage through half-wave rectification after isolation by a pulse transformer. At the same time, by changing the peripheral parameters, the voltage can be increased or decreased to meet the requirements of the product.

[0011] The present invention will be described in further detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the circuit for converting 1.8VDC to 3.3VDC. DETAILED DESCRIPTION

[0013] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose, the specific implementation methods, structural features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and embodiments.

[0014] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0015] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "aligned", "overlap", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0016] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present utility model, unless otherwise specified, "plurality" means two or more.

[0017] Example 1

[0018] In order to solve the problem that the existing DC power supply cannot stably use a voltage lower than 3.3VDC to form a stable 3.3VDC voltage to power electronic devices.

[0019] The utility model is described in a Figure 1The circuit for converting 1.8VDC to 3.3VDC shown in the figure comprises a circuit + input terminal and a circuit - input terminal, a capacitor C10 is arranged between the circuit + input terminal and the circuit - input terminal, the + input terminal is electrically connected to pin 3 of the converter, the circuit - input terminal is electrically connected to pin 2 of the converter, pin 1 of the converter is electrically connected to pin 3 of the converter, an inductor L3 is arranged between pin 3 of the converter and pin 6 of the converter, pin 5 of the converter is electrically connected to pin 2 of the isolation chip, pin 2 of the isolation chip is electrically connected to pin 3 of the isolation chip, pin 4 of the converter is electrically connected to pin 6 of the isolation chip, pin 6 of the isolation chip is electrically connected to pin 7 of the isolation chip, and pin 5 of the converter is electrically connected to pin 6 of the isolation chip. A capacitor C11 is arranged between the pin 4 of the converter, a capacitor C12 is further arranged between the pin 5 of the converter and the pin 4 of the converter, the resistor R23 and the capacitor C13 are connected in parallel and arranged between the pin 1 of the isolation chip and the pin 6 of the isolation chip, the pin 8 of the isolation chip and the pin 5 of the isolation chip are electrically connected to the two input ends of the transformer TR1 respectively, the two output ends of the transformer TR1 are electrically connected to the two input ends of the rectifier bridge, one output end of the rectifier bridge is electrically connected to one end of the inductor L4, the other end of the inductor L4 is the circuit + output end, the other output end of the rectifier bridge is electrically connected to one end of the inductor L5, the other end of the inductor L5 is the circuit - output end, and a capacitor C14 is further arranged between the two output ends of the rectifier bridge.

[0020] Furthermore, the converter is a step-up DC / DC converter, and its model is LTC3525-3.3.

[0021] Furthermore, the isolation chip model is SGM46000.

[0022] Furthermore, the model of the rectifier bridge is KMB14F.

[0023] In summary, the 1.8VDC to 3.3VDC conversion circuit provided by the utility model has the following advantages: the circuit adopts a high-efficiency, synchronous boost DC / DC converter LTC3525-3.3 with an output disconnect function, and the device has a built-in 0.5Ω N-channel MOSFET switch and a 0.8Ω P-channel synchronous rectifier. It ensures that the internal power supply (battery) product can stably output 3.3VDC power to power the subsequent circuit under the condition of extremely low input voltage (1.8VDC in parallel state), thereby greatly extending the battery life in portable applications and ensuring the stability of circuit operation.

[0024] At the same time, the subsequent circuit adds an isolation drive circuit to output the 3.3VDC voltage output by LTC3525 to the DC-DC isolation chip SGM46000. The isolation chip converts the DC voltage into an alternating signal with a switching frequency of about 150KHz through an internal oscillator, and restores it to the required DC voltage through half-wave rectification after isolation by a pulse transformer. At the same time, by changing the peripheral parameters, the voltage can be increased or decreased to meet the power supply requirements of the product.

[0025] When this circuit is used in medical equipment, it can achieve true electrical physical isolation, with the input and output isolation voltage reaching 1500V.

[0026] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A circuit for converting 1.8VDC to 3.3VDC, comprising a circuit + input terminal and a circuit - input terminal, characterized in that: A capacitor C10 is arranged between the +input end of the circuit and the -input end of the circuit, the +input end is electrically connected to pin 3 of the converter, the -input end of the circuit is electrically connected to pin 2 of the converter, pin 1 of the converter is electrically connected to pin 3 of the converter, an inductor L3 is arranged between pin 3 of the converter and pin 6 of the converter, pin 5 of the converter is electrically connected to pin 2 of the isolation chip, pin 2 of the isolation chip is electrically connected to pin 3 of the isolation chip, pin 4 of the converter is electrically connected to pin 6 of the isolation chip, pin 6 of the isolation chip is electrically connected to pin 7 of the isolation chip, a capacitor C11 is arranged between pin 5 of the converter and pin 4 of the converter, and the A capacitor C12 is further provided between pin 5 of the converter and pin 4 of the converter. After resistor R23 and capacitor C13 are connected in parallel, they are provided between pin 1 of the isolation chip and pin 6 of the isolation chip. Pin 8 of the isolation chip and pin 5 of the isolation chip are electrically connected to two input ends of the transformer TR1 respectively. Two output ends of the transformer TR1 are electrically connected to two input ends of the rectifier bridge. One output end of the rectifier bridge is electrically connected to one end of the inductor L4, and the other end of the inductor L4 is the circuit + output end. The other output end of the rectifier bridge is electrically connected to one end of the inductor L5, and the other end of the inductor L5 is the circuit - output end. A capacitor C14 is further provided between the two output ends of the rectifier bridge.

2. A 1.8VDC to 3.3VDC conversion circuit as claimed in claim 1, characterized in that: The converter is a step-up DC / DC converter, and its model is LTC3525-3.

3.

3. The circuit for converting 1.8VDC to 3.3VDC as claimed in claim 1, characterized in that: The isolation chip model is SGM46000.

4. The circuit for converting 1.8VDC to 3.3VDC as claimed in claim 1, characterized in that: The model of the rectifier bridge is KMB14F.

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