An encoder powered switching circuit
By using a bridge-connected diode and switch module design, the problem of the encoder failing to work properly under reverse connection conditions is solved, enabling the encoder to work normally under different connection methods, improving flexibility and reducing the failure rate.
Patent Information
- Application Number
- CN202521957145.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-11
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-09-11
AI Technical Summary
Existing encoder protection circuits can only prevent reverse connection and cannot function properly under both positive and reverse connection conditions, resulting in inconvenience in installation and maintenance.
The design employs a bridge-connected diode and switch module, combined with NMOS and PMOS transistors, to enable flexible switching of the encoder power supply, ensuring normal operation whether connected in the correct or reverse direction.
It improves the flexibility and adaptability of the encoder, reduces the failure rate, and enables the encoder to work normally under different access methods.
Smart Images
Figure CN224683936U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of encoder technology, and in particular to an encoder power supply switching circuit. Background Technology
[0002] Currently, encoders are becoming increasingly important in the servo system field, and as high-precision products, their protection is particularly crucial. Encoder protection circuits mainly employ the following two methods: 1. Using diodes, the forward conduction and reverse cutoff characteristics of diodes are utilized to achieve reverse connection protection; 2. Utilize MOSFET characteristics to achieve reverse connection protection.
[0003] Current protection methods can only protect the circuit from reverse connection. When reverse connection occurs, the encoder cannot work properly, causing inconvenience to the installation and maintenance of the encoder. Summary of the Invention
[0004] This application provides an encoder power supply switching circuit, which has the advantage that the encoder can work normally whether the power line connected in the correct direction or in the reverse direction, thereby improving the encoder's flexibility and adaptability and reducing the encoder failure rate.
[0005] The above-mentioned objective of this application is achieved through the following technical solution: an encoder power supply switching circuit, characterized in that it includes diodes D1, D2, D3, and D4 connected in a bridge manner, diodes D1, D2, D3, and D4 forming a bridge circuit, the input terminal of the bridge circuit being connected to external power inputs INA and INB, and the output terminals AO and BO of the bridge circuit serving as encoder power supplies. It also includes a battery BAT and a switching module. The output terminal of the battery BAT is connected to the switching module. The switching module includes a first switching circuit, a second switching circuit, and a power output terminal, wherein: The first switching circuit is set between the encoder power supply and the power output terminal. The first switching circuit includes a first N-MOSFET and a third P-MOSFET. The third P-MOSFET is connected between the encoder power supply and the power output terminal. The gate of the third P-MOSFET is grounded through the first N-MOSFET. The gate of the first N-MOSFET is connected to the encoder power supply. The gate of the third P-MOSFET is also connected to the power output terminal. The second switching circuit is set between the encoder battery BAT and the power output terminal. The second switching circuit includes a first PMOS transistor. The encoder battery is connected to the drain of the first PMOS transistor, the power output terminal is connected to the source of the first PMOS transistor, and the gate of the first PMOS transistor is connected to the encoder power supply. When the encoder is powered on, the first switch circuit is turned on and the second switch circuit is turned off; when the encoder is powered off, the first switch circuit is turned off and the second switch circuit is turned on.
[0006] Furthermore, diodes D1, D2, D3, and D4 are selected as voltage drop diodes, model number Dongke DK5V60R25H.
[0007] Furthermore, the diode is connected in series with a magnetic bead.
[0008] Furthermore, the diode is connected in parallel with a capacitor.
[0009] In summary, the beneficial effects of this application are: the circuit can convert the encoder power supply to an output suitable for the encoder load regardless of whether it is connected in the correct or reverse direction, ensuring normal encoder operation, improving encoder flexibility and adaptability, and reducing encoder failure rate. The switching module allows the encoder power supply to switch between external power and battery power. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of the circuit structure of an embodiment of this application; Figure 2 This is a schematic diagram of the circuit structure of another embodiment of this application. Detailed Implementation
[0011] The specific embodiments of this application are described in detail below with reference to the accompanying drawings.
[0012] Example 1: An encoder power supply switching circuit, reference Figure 1 It includes diodes D1, D2, D3, and D4 connected in a bridge configuration. Diodes D1, D2, D3, and D4 form a bridge circuit. The input terminals of the bridge circuit are connected to external power inputs INA and INB. The output terminals AO and BO of the bridge circuit serve as the encoder power supply for the encoder load.
[0013] The circuit described above can be packaged as a chip, or it can be implemented using a dedicated ASIC to achieve modular design.
[0014] The diodes D1, D2, D3, and D4 are selected as voltage drop diodes, model number Dongke DK5V60R25H.
[0015] It also includes a battery BAT and a switching module. The output terminal of the battery BAT is connected to the switching module. The switching module includes a first switching circuit, a second switching circuit, and a power output terminal, wherein: The first switching circuit is located between the encoder power supply and the power output terminal, and the second switching circuit is located between the encoder battery and the power output terminal. When the encoder power supply is on, the first switching circuit is turned on and the second switching circuit is turned off. When the encoder power supply is off, the first switching circuit is turned off and the second switching circuit is turned on.
[0016] refer to Figure 2The first switching circuit includes a first NMOS transistor Q6 and a third PMOS transistor Q4. The third PMOS transistor Q4 is connected between the encoder power supply and the power output terminal. The gate of the third PMOS transistor Q4 is grounded through the first NMOS transistor Q6. The gate of the first NMOS transistor Q6 is connected to the encoder power supply, and the gate of the third PMOS transistor Q4 is also connected to the power output terminal. The gate of the third PMOS transistor is connected to the power output terminal through a first resistor R9.
[0017] The second switching circuit includes a first PMOS transistor Q1, whose gate is connected to the encoder power supply. The encoder battery is connected to the drain of the first PMOS transistor Q1, and the power output terminal is connected to the source of the first PMOS transistor Q1. The gate of the first PMOS transistor Q1 is connected to the encoder power supply. A resistor R7 is connected to the gate of the first PMOS transistor, and the other end of the resistor R7 is grounded. The resistor R7 is selected with a large resistance value, such as 10K ohms, to control the voltage of the gate of the first PMOS transistor Q1 to a high voltage state when the encoder power supply is on, thus preventing the first PMOS transistor Q1 from conducting.
[0018] In this scheme, when the encoder power supply is on, the first NMOS transistor Q6 is turned on, the first PMOS transistor Q5 is turned off, and the third PMOS transistor Q4 is turned on. At this time, the encoder power supply P5V achieves zero voltage drop at the load end. When the power supply is turned off, Q6 is turned off, Q4 is turned off, and Q5 is turned on. At this time, the encoder battery BAT achieves zero voltage drop at the load end.
[0019] The first switching circuit further includes a fourth PMOS transistor and / or a fourth diode, wherein the fourth PMOS transistor or the fourth diode is connected in parallel with the third PMOS transistor, and the fourth PMOS transistor and the third PMOS transistor are in opposite directions, and the gates of the fourth PMOS transistor and the third PMOS transistor are connected to each other.
[0020] The diode is connected in series with a ferrite bead, and the diode is connected in parallel with a capacitor. The ferrite bead in series is used to suppress high-frequency noise and spike interference, and the capacitor in parallel is used to reduce high-frequency interference.
[0021] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the inventive concept of this application, and these all fall within the protection scope of this application.
Claims
1. An encoder power supply switching circuit, characterized in that, The circuit includes diodes D1, D2, D3, and D4 connected in a bridge configuration. The input terminals of the bridge circuit are connected to external power inputs INA and INB, and the output terminals AO and BO of the bridge circuit serve as the encoder power supply. It also includes a battery BAT and a switching module. The output terminal of the battery BAT is connected to the switching module. The switching module includes a first switching circuit, a second switching circuit, and a power output terminal, wherein: The first switching circuit is set between the encoder power supply and the power output terminal. The first switching circuit includes a first N-MOSFET and a third P-MOSFET. The third P-MOSFET is connected between the encoder power supply and the power output terminal. The gate of the third P-MOSFET is grounded through the first N-MOSFET. The gate of the first N-MOSFET is connected to the encoder power supply. The gate of the third P-MOSFET is also connected to the power output terminal. The second switching circuit is set between the encoder battery BAT and the power output terminal. The second switching circuit includes a first PMOS transistor. The encoder battery is connected to the drain of the first PMOS transistor, the power output terminal is connected to the source of the first PMOS transistor, and the gate of the first PMOS transistor is connected to the encoder power supply. When the encoder is powered on, the first switch circuit is turned on and the second switch circuit is turned off; when the encoder is powered off, the first switch circuit is turned off and the second switch circuit is turned on.
2. The encoder power supply switching circuit according to claim 1, characterized in that, The diodes D1, D2, D3, and D4 are selected as voltage drop diodes, model number Dongke DK5V60R25H.
3. The encoder power supply switching circuit according to claim 1, characterized in that, The diode is connected in series with a magnetic bead.
4. The encoder power supply switching circuit according to claim 1, characterized in that, The diode is connected in parallel with a capacitor.