Multi-voltage isolation power supply circuit

Abstract

The utility model provides a multi-voltage isolation power supply circuit, and relates to the technical field of power supply circuits. Comprising an analog input power supply circuit, an analog output power supply circuit, a first digital power supply circuit and a second digital power supply circuit which are respectively provided with a power supply isolation transformer. The analog input power supply circuit, the analog output power supply circuit, the first digital power supply circuit and the second digital power supply circuit are respectively provided with a driving circuit, so that the analog output or input power supply circuit can be prevented from interfering with the digital power supply circuits. And moreover, mutual interference between the analog input power supply circuit and the analog output power supply circuit and interference between digital power supply circuits with different voltages can be avoided, so that the reliability of equipment can be improved.

Description

Technical Field

[0001] This utility model relates to the field of circuit design technology, and in particular to a multi-voltage isolated power supply circuit. Background Technology

[0002] Industrial automation equipment operates in complex environments and is frequently subjected to interference from internal and external electromagnetic signals. Power supply circuits, in particular, are susceptible to external or internal interference, leading to problems such as system crashes, incorrect command transmission / reception, or circuit module damage. This is especially true for digital and analog circuits on circuit boards. Power fluctuations in analog circuits can interfere with digital circuits, and even within analog power supply circuits, interference signals can arise between the input and output circuits, causing abnormal circuit signals. This is especially problematic for precision equipment with numerous sensors; signal interference can cause erroneous sensor output signals, leading to incorrect judgments in the control circuit and ultimately, functional errors. Therefore, reducing interference between power supply circuits is a crucial way to improve equipment reliability. Utility Model Content

[0003] This utility model is achieved through the following technical solution: a multi-voltage isolated power supply circuit. It includes an analog input power supply circuit 10, an analog output power supply circuit 11, a first digital power supply circuit 12, and a second digital power supply circuit 13. Each of the analog input power supply circuit 10, analog output power supply circuit 11, first digital power supply circuit 12, and second digital power supply circuit 13 is equipped with a power isolation transformer, and each of the analog input power supply circuit 10, analog output power supply circuit 11, first digital power supply circuit 12, and second digital power supply circuit 13 is equipped with a drive circuit.

[0004] Preferably, the analog input power supply circuit 10 includes a +12V analog input voltage circuit, a +3.3V analog input voltage circuit, and a -12V analog input voltage circuit.

[0005] Preferably, the analog output power supply circuit 11 includes a +12V analog output voltage circuit, a +3.3V analog output voltage circuit, and a -12V analog output voltage circuit.

[0006] Preferably, the first digital power supply circuit 12 is a +3.3V digital power supply circuit.

[0007] Preferably, the second digital power supply circuit 13 is a +5V digital power supply circuit.

[0008] Preferably, the power isolation transformer includes an oscillator and a gate driver circuit.

[0009] Preferably, the +12V analog input power supply circuit and the +3.3V analog input voltage circuit rectify the voltage output by the power isolation transformer through diode D36;

[0010] The +12V analog input voltage circuit also includes capacitors C185, C186, C187 and resistor R162, which together form a filter circuit for filtering.

[0011] The +3.3V analog input voltage circuit includes capacitors C298, C299, and C217, and a transformer module U28. Capacitors C298, C299, and C217 are used to filter the signal output from diode D36. The signal is then transformed by the transformer module U28. The signal output from the transformer module U28 is further filtered by a filter circuit composed of capacitors C213, C296, C297, and resistor R165.

[0012] Preferably, the -12V analog input voltage circuit includes diode D37, wherein diode D37 is configured to be inversely related to diode D36;

[0013] The -12V analog input voltage circuit also includes capacitors C292, C293, C294 and resistor R158. These capacitors form a filter circuit for filtering.

[0014] Preferably, the +12V analog output voltage circuit and the +3.3V analog output voltage circuit rectify the voltage output by the power isolation transformer through diode D39;

[0015] The +12V analog output voltage circuit includes capacitors C184, C202, C206, and resistor R160. The capacitors C184, C202, C206, and R160 form a filter circuit for filtering.

[0016] The +3.3V analog output voltage circuit includes capacitors C210, C211, and C212, and transformer module U52. Capacitors C210, C211, and C212 are used to filter the signal output by diode D39. Transformer module U52 is used for voltage transformation. The signal output by transformer module U52 can be filtered by a filter circuit composed of capacitors C207, C208, C209, and resistor R159.

[0017] The -12V analog output voltage circuit includes a diode D40, and also includes capacitors C190, C204, C205 and resistor R161. The filter circuit composed of capacitors C190, C204, C205 and resistor R161 is used for filtering.

[0018] This invention provides a multi-voltage isolated power supply circuit, which has the following advantages: By providing independent power isolation transformers and corresponding drive circuits for each of the analog input power supply circuit, analog output power supply circuit, first digital power supply circuit, and second digital power supply circuit, this invention avoids interference between the analog output or input power supply circuit and the digital power supply circuit, and also avoids mutual interference between the analog input power supply circuit and the analog output power supply circuit, as well as interference between digital power supply circuits with different voltages, thus improving the reliability of the equipment. Attached Figure Description

[0019] Figure 1 The diagram shown is a schematic diagram of the circuit structure of the multi-voltage isolated power supply circuit that implements this utility model.

[0020] Figure 2 The diagram shows the circuit structure of the analog input power supply circuit for implementing the multi-voltage isolated power supply circuit of this utility model.

[0021] Figure 3 The diagram shows a schematic of the analog output power supply circuit of the multi-voltage isolated power supply circuit that implements this utility model.

[0022] Figure 4 The diagram shows the circuit structure of the first digital power supply circuit implementing the multi-voltage isolated power supply circuit of this utility model.

[0023] Figure 5 The diagram shows the circuit structure of the second digital power supply circuit for implementing the multi-voltage isolated power supply circuit of this utility model. Detailed Implementation

[0024] This utility model provides a multi-voltage isolated power supply circuit.

[0025] Please see Figure 1The diagram shows a schematic of the circuit structure of the multi-voltage isolated power supply circuit implementing this invention. The multi-voltage isolated power supply circuit implementing this invention includes an analog input power supply circuit 10, an analog output power supply circuit 11, a first digital power supply circuit 12, and a second digital power supply circuit 13. Each of the analog input power supply circuit 10, analog output power supply circuit 11, first digital power supply circuit 12, and second digital power supply circuit 13 is equipped with an independent power isolation transformer and a corresponding drive circuit. The analog input power supply circuit 10 has multiple analog input voltage circuits, while the analog output power supply circuit 11 has multiple analog output voltage circuits.

[0026] The analog input power supply circuit 10 is provided with +12V, +3.3V and -12V analog input voltage circuits, the analog output power supply circuit is provided with +12V, +3.3V and -12V analog output voltage circuits, the first digital power supply circuit 12 is a +3.3V digital power supply circuit, and the second digital power supply circuit 13 is a +5V digital power supply circuit.

[0027] In practical implementation, the drive circuit of the power isolation transformer uses a Texas Instruments SN6501 monolithic oscillator / power driver, which includes oscillator and gate driver circuitry, such as... Figures 2 to 5 As shown, its fourth and fifth pins 4 and 5 are connected to ground, the first pin 1 is connected to the bottom tap (unlabeled) of the primary winding of the power isolation transformer, the second pin 2 is connected to the external +5V DC power supply and the middle tap (unlabeled) of the primary winding of the power isolation transformer, and the third pin 3 is connected to the upper tap (unlabeled) of the primary winding of the power isolation transformer.

[0028] Please see Figure 2 As shown, the analog input power supply circuit 10 is provided with +12V, +3.3V and -12V analog input voltage circuits, all of which are led out from the upper tap (unlabeled) of the secondary winding of the power isolation transformer. The +12V and +3.3V analog input voltage circuits rectify the voltage output by the power isolation transformer through diode D36. The +12V analog input voltage circuit is also provided with a filter circuit composed of capacitors C185, C186, C187 and resistor R162 to filter the voltage, thereby forming a stable +12V analog input voltage.

[0029] The +3.3V analog input voltage circuit also includes capacitors C298, C299, and C217 to filter the signal output from diode D36. The signal is then transformed by transformer module U28, and the signal output from transformer module U28 is further filtered by a filter circuit composed of capacitors C213, C296, C297, and resistor R165, thereby forming a stable +3.3V analog input voltage.

[0030] The -12V analog input voltage circuit includes diode D37, which is set in reverse phase with diode D36. That is, the negative terminal of diode D37 is connected to the upper tap (unlabeled) of the secondary winding of the power isolation transformer. The -12V analog input voltage circuit also has a filter circuit composed of capacitors C292, C293, C294 and resistor R158 to filter and form a stable -12V analog input voltage.

[0031] Please see Figure 3 As shown, the analog output power supply circuit 11 is provided with +12V, +3.3V and -12V analog output voltage circuits, all of which are led out from the upper tap (unlabeled) of the secondary winding of the power isolation transformer. The +12V and +3.3V analog output voltage circuits rectify the voltage output by the power isolation transformer through diode D39. The +12V analog output voltage circuit is also provided with a filter circuit composed of capacitors C184, C202, C206 and resistor R160 to filter the voltage, thereby forming a stable +12V analog output voltage.

[0032] The +3.3V analog output voltage circuit also includes capacitors C210, C211, and C212 to filter the signal output from diode D39. The signal is then transformed by transformer module U52, and the signal output from transformer module U52 is further filtered by a filter circuit composed of capacitors C207, C208, C209, and resistor R159, thereby forming a stable +3.3V analog output voltage.

[0033] The -12V analog output voltage circuit includes diode D40, in which diode D39 is set in reverse phase with diode D40, that is, the negative terminal of diode D40 is connected to the upper tap (unlabeled) of the secondary winding of the power isolation transformer. The -12V analog output voltage circuit also has a filter circuit composed of capacitors C190, C204, C205 and resistor R161 to filter and form a stable -12V analog output voltage.

[0034] Please see Figure 4As shown, the +3.3V digital power supply circuit 12 includes a rectifier circuit composed of two diodes D38 and D35. The positive terminals of diodes D38 and D35 are connected to the upper tap (unlabeled) and lower tap (unlabeled) of the secondary winding of the power isolation transformer, respectively. The +3.3V digital power supply circuit also includes capacitors C193, C201, and C203 to filter the signal output from the rectifier circuit. The signal is then transformed by the transformer module U43, and the signal output from the transformer module U43 is further filtered by a filter circuit composed of capacitors C182, C191, C192, and resistor R163, thereby forming a stable +3.3V digital circuit voltage. In practical implementation, this +3.3V digital circuit voltage is used to power sensors such as temperature sensors.

[0035] Please see Figure 5 As shown, the +5V digital power supply circuit 13 includes a rectifier circuit composed of two diodes D42 and D41. The positive terminals of diodes D42 and D41 are connected to the upper tap (unlabeled) and lower tap (unlabeled) of the secondary winding of the power isolation transformer, respectively. The +5V digital power supply circuit also includes capacitors C194, C195, and C196 to filter the signal output from the rectifier circuit. The signal is then transformed by the transformer module U40, and the signal output from the transformer module U40 is further filtered by a filter circuit composed of capacitors C198, C199, C200, and resistor R164, thereby forming a stable +5V digital circuit voltage. In practical implementation, this +5V digital circuit voltage is used to provide power to circuits such as RS485 interface circuits.

[0036] In practice, the aforementioned transformer module is a Texas Instruments LP2992AIM5 series chip.

[0037] Compared with the prior art, this utility model provides independent power isolation transformers and corresponding drive circuits for each of the analog input power circuit 10, analog output power circuit 11, first digital power circuit 12 and second digital power circuit 13. This avoids interference between the analog output or input power circuits and the digital power circuits, and also avoids mutual interference between the analog input power circuit and the analog output power circuit, as well as interference between digital power circuits with different voltages. This improves the reliability of the equipment.

[0038] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A multi-voltage isolated power supply circuit, comprising an analog input power supply circuit (10), an analog output power supply circuit (11), a first digital power supply circuit (12), and a second digital power supply circuit (13), characterized in that: The analog input power supply circuit (10), analog output power supply circuit (11), first digital power supply circuit (12) and second digital power supply circuit (13) are all equipped with power isolation transformers, and the analog input power supply circuit (10), analog output power supply circuit (11), first digital power supply circuit (12) and second digital power supply circuit (13) are all equipped with driving circuits.

2. The multi-voltage isolation power supply circuit according to claim 1, characterized in that: The analog input power supply circuit (10) includes a +12V analog input voltage circuit, a +3.3V analog input voltage circuit and a -12V analog input voltage circuit.

3. The multi-voltage isolation power supply circuit according to claim 2, characterized in that: The analog output power supply circuit (11) includes a +12V analog output voltage circuit, a +3.3V analog output voltage circuit and a -12V analog output voltage circuit.

4. A multi-voltage isolation power supply circuit according to claim 3, characterized in that: The first digital power supply circuit (12) is a +3.3V digital power supply circuit.

5. A multi-voltage isolated power supply circuit according to claim 4, characterized in that: The second digital power supply circuit (13) is a +5V digital power supply circuit.

6. A multi-voltage isolated power supply circuit according to claim 5, characterized in that: The power isolation transformer includes an oscillator and a gate driver circuit.

7. A multi-voltage isolated power supply circuit according to claim 6, characterized in that: The +12V analog input voltage circuit and the +3.3V analog input voltage circuit rectify the voltage output from the power isolation transformer through diode D36; The +12V analog input voltage circuit also includes capacitors C185, C186, C187 and resistor R162, which together form a filter circuit for filtering. The +3.3V analog input voltage circuit includes capacitors C298, C299, and C217, and a transformer module U28. Capacitors C298, C299, and C217 are used to filter the signal output from diode D36. The signal is then transformed by the transformer module U28. The signal output from the transformer module U28 is further filtered by a filter circuit composed of capacitors C213, C296, C297, and resistor R165.

8. A multi-voltage isolated power supply circuit according to claim 7, characterized in that: The -12V analog input voltage circuit includes diode D37, wherein diode D37 is set in reverse phase with diode D36; The -12V analog input voltage circuit also includes capacitors C292, C293, C294 and resistor R158. The capacitors C292, C293, C294 and R158 form a filter circuit for filtering.

9. A multi-voltage isolation power supply circuit according to claim 8, characterized in that: The +12V analog output voltage circuit and the +3.3V analog output voltage circuit rectify the voltage output by the power isolation transformer through diode D39; The +12V analog output voltage circuit includes capacitors C184, C202, C206, and resistor R160. The capacitors C184, C202, C206, and R160 form a filter circuit for filtering. The +3.3V analog output voltage circuit includes capacitors C210, C211, and C212, and transformer module U52. Capacitors C210, C211, and C212 are used to filter the signal output by diode D39. Transformer module U52 is used for voltage transformation. The signal output by transformer module U52 can be filtered by a filter circuit composed of capacitors C207, C208, C209, and resistor R159. The -12V analog output voltage circuit includes a diode D40, and also includes capacitors C190, C204, C205 and resistor R161. The filter circuit composed of capacitors C190, C204, C205 and resistor R161 is used for filtering.

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