Controller circuit board

Abstract

This utility model relates to the field of electronic control device technology, specifically a controller circuit board, including a substrate. Three sets of drive units arranged in a triangular symmetrical pattern are provided on the substrate. Each drive unit set includes an upper-bridge MOSFET, a lower-bridge MOSFET, an upper-bridge drive group, a lower-bridge drive group, and a common heat dissipation copper area. The upper-bridge MOSFET and the lower-bridge MOSFET are symmetrically mounted along the longitudinal centerline of the substrate. The upper-bridge drive group is located adjacent to the gate pin area of ​​the upper-bridge MOSFET, and the lower-bridge drive group is located adjacent to the gate pin area of ​​the lower-bridge MOSFET. The common heat dissipation copper area is located directly below and thermally contacts the drain pads of the upper-bridge MOSFET and the lower-bridge MOSFET. This controller circuit board can effectively shorten the current loop, reduce parasitic inductance, thereby reducing switching noise and voltage spikes, and improving drive efficiency and operational reliability.

Description

Technical Field

[0001] This utility model relates to the field of electronic control device technology, specifically to a controller circuit board. Background Technology

[0002] With the increasing popularity of light electric vehicles such as electric bicycles, the controller circuit board, a core control component, plays a crucial role in the overall vehicle performance and safety. The controller circuit board is mainly used to drive the motor, process sensor signals, and coordinate the operation of various functional modules; it is the central hub connecting user operation and vehicle response.

[0003] While current controller circuit boards on the market have achieved basic driving and sensing functions, there is still room for optimization in their structural layout. For example, utility model patent CN210983066U discloses a controller circuit board integrating an attitude sensor and a motor drive module, which reduces external wiring by setting multiple drive circuits and interfaces on the substrate. However, in this solution, the power MOSFETs and their driving transistors in the three drive circuits are all laid out in a distributed manner, resulting in a long current loop and large parasitic inductance. This easily causes voltage spikes and electromagnetic interference during high-frequency switching, which not only affects the driving efficiency but may also cause MOSFET mis-triggering or thermal failure. Utility Model Content

[0004] The purpose of this invention is to provide a controller circuit board to solve the problems mentioned in the background art, such as long current loops and large parasitic inductance caused by the dispersed layout of drive circuit components in current controller circuit boards, which in turn lead to switching interference, reduced efficiency and decreased reliability.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a controller circuit board, including a substrate, on which three sets of driving units are arranged in a triangular symmetrical manner. Each set of driving units includes an upper-bridge MOSFET, a lower-bridge MOSFET, an upper-bridge driving group, a lower-bridge driving group, and a common heat dissipation copper area. The upper-bridge MOSFET and the lower-bridge MOSFET are symmetrically mounted along the longitudinal centerline of the substrate. The upper-bridge driving group is located in the gate pin area of ​​the upper-bridge MOSFET, and the lower-bridge driving group is located in the gate pin area of ​​the lower-bridge MOSFET. The common heat dissipation copper area is located directly below the drain pads of the upper-bridge MOSFET and the lower-bridge MOSFET and is in thermal contact with them.

[0006] Preferably, the upper bridge drive group is composed of a first NPN transistor, a PNP transistor, and a second NPN transistor cascaded in sequence, and the three are linearly distributed along the transverse direction of the substrate. The collector pad of the first NPN transistor and the base pad of the PNP transistor are directly connected through the top layer metal trace.

[0007] Preferably, the lower bridge drive group includes a third NPN transistor, a second PNP transistor, and a fourth NPN transistor. The third NPN transistor and the second PNP transistor share the same ground pad. The emitter pad of the fourth NPN transistor is adjacent to the gate pad of the lower bridge MOS transistor and the distance between them does not exceed 2 mm.

[0008] Preferably, the common heat dissipation copper area is a solid copper layer embedded in the top layer of the substrate, and the area of ​​the common heat dissipation copper area covers the total projected area of ​​the drain pads of the upper bridge MOSFET and the lower bridge MOSFET. Furthermore, the common heat dissipation copper area extends downward to the two ground planes of the inner layer of the substrate, and the three copper layers are interconnected through multiple thermal vias.

[0009] Preferably, the drive unit corresponds to the three phases U, V, and W of the motor and is evenly distributed in a 120-degree circle along the edge of the substrate. Furthermore, each group of drive units has an isolation groove between the upper bridge MOS transistor and the lower bridge MOS transistor. The isolation groove is a copper-free channel excavated on the top layer of the substrate and has a width of not less than 1.5 mm.

[0010] Preferably, the source pad of the upper bridge MOSFET and the drain pad of the lower bridge MOSFET are directly connected by a wide copper strip on the top layer of the substrate, and the width of the wide copper strip is not less than 5 mm.

[0011] Compared with existing technologies, the beneficial effects of this invention are: the controller circuit board can effectively shorten the current loop and reduce parasitic inductance, thereby reducing switching noise and voltage spikes, and improving drive efficiency and operational reliability. By arranging the upper-bridge MOSFETs, lower-bridge MOSFETs, and their corresponding upper-bridge and lower-bridge drive groups adjacent to each other, and combining them with a shared heat dissipation copper area as a low-impedance return path and heat conduction structure, the controller circuit board significantly optimizes the electrical and thermal performance of the high-frequency power circuit. Simultaneously, the three drive units are arranged in a triangular symmetrical configuration, further balancing the overall electromagnetic and thermal distribution and enhancing system stability. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the controller circuit board structure of this utility model; Figure 2 This is a schematic diagram of the common heat dissipation copper area structure of the controller circuit board of this utility model; Figure 3 This is a partial side view of the drive unit of the controller circuit board of this utility model.

[0013] In the diagram: 1. Substrate; 2. Driving unit; 21. Upper bridge MOSFET; 22. Lower bridge MOSFET; 23. Upper bridge driving group; 231. First NPN transistor; 232. PNP transistor; 233. Second NPN transistor; 24. Lower bridge driving group; 241. Third NPN transistor; 242. Second PNP transistor; 243. Fourth NPN transistor; 25. Common heat dissipation copper area; 251. Thermal via; 26. Wide copper strip. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] Please see Figure 1-3This utility model provides a technical solution: a controller circuit board, including a substrate 1, on which three sets of drive units 2 are arranged in a triangular symmetrical manner. Each drive unit 2 includes an upper bridge MOSFET 21, a lower bridge MOSFET 22, an upper bridge drive group 23, a lower bridge drive group 24, and a common heat dissipation copper area 25. The upper bridge MOSFET 21 and the lower bridge MOSFET 22 are symmetrically mounted along the longitudinal centerline of the substrate 1. The upper bridge drive group 23 is located adjacent to the gate pin area of ​​the upper bridge MOSFET 21, and the lower bridge drive group 24 is located adjacent to the gate pin area of ​​the lower bridge MOSFET 22. The common heat dissipation copper area 25 is located directly below and in thermal contact with the drain pads of the upper bridge MOSFET 21 and the lower bridge MOSFET 22. In this structure, the upper bridge drive group 23 is located adjacent to the upper bridge MOSFET 22. The gate pin region of MOSFET 21 can provide a switching drive signal to it with an extremely short path. Similarly, the lower bridge drive group 24 is adjacent to the gate pin region of the lower bridge MOSFET 22, realizing fast and precise control of the lower bridge MOSFET 22. At the same time, the common heat dissipation copper area 25 is located directly below the drain pads of the upper bridge MOSFET 21 and the lower bridge MOSFET 22 and is in direct thermal contact with them. During high-frequency switching, it not only forms a common heat dissipation channel with low thermal resistance, but also serves as a low-impedance current return plane, so that the power current loop flowing through the upper bridge MOSFET 21 and the lower bridge MOSFET 22 is constrained within a very small local space. The three drive units 2 further balance the electrical and thermal distribution between each phase. The above components, through the close cooperation of their spatial positions, significantly improve the efficiency of the switching process. The drive signal path and power current loop are shortened, effectively reducing parasitic inductance and loop impedance, thereby suppressing voltage spikes and electromagnetic interference generated by switching transients, improving the stability and synchronization of MOSFET switching, and avoiding false triggering, oscillation, or thermal concentration failures caused by excessively long loops or loose layouts. This solves the problems of low efficiency and insufficient reliability caused by the dispersion of drive and power components in existing controller circuit boards. The upper bridge drive group 23 is composed of a first NPN transistor 231, a PNP transistor 232, and a second NPN transistor 233 cascaded sequentially. The three are linearly distributed laterally along the substrate 1, and the collector pad of the first NPN transistor 231 and the base pad of the PNP transistor 232 are directly connected through the top layer metal trace. This design creates a high-gain, fast-response drive path. The top-layer metal trace directly connects the collector pad of the first NPN transistor 231 to the base pad of the PNP transistor 232, further shortening the signal transmission path and reducing the drive circuit impedance and delay. This ensures that the upper-bridge MOSFET 21 can be quickly and reliably turned on or off. The lower-bridge drive group 24 includes a third NPN transistor 241, a second PNP transistor 242, and a fourth NPN transistor 243. The third NPN transistor 241 and the second PNP transistor 242 share the same ground pad. The emitter pad of the fourth NPN transistor 243 is adjacent to the gate pad of the lower-bridge MOSFET 22 with a spacing of no more than 2 mm. This structure reduces wiring redundancy by sharing a ground pad.To improve the grounding consistency of the lower bridge driver group 24, and to place the emitter pad of the fourth NPN transistor 243 adjacent to the gate pad of the lower bridge MOSFET 22, the final stage drive signal path is greatly shortened, effectively reducing parasitic inductance and switching delay, ensuring that the lower bridge MOSFET 22 obtains a fast and stable gate drive signal. The shared heat dissipation copper area 25 is a solid copper layer embedded in the top layer of the substrate 1, and the area of ​​the shared heat dissipation copper area 25 covers the total projected area of ​​the drain pads of the upper bridge MOSFET 21 and the lower bridge MOSFET 22. Furthermore, the shared heat dissipation copper area 25 extends downward to the two ground planes of the inner layer of the substrate 1, and the three copper layers are interconnected through multiple thermal vias 251. This structure reduces wiring redundancy through the shared ground pad, improves the grounding consistency of the lower bridge driver group 24, and places the emitter pad of the fourth NPN transistor 243 adjacent to the gate pad of the lower bridge MOSFET 22, greatly shortening the final stage drive signal path, effectively reducing parasitic inductance and switching delay, and ensuring that the lower bridge MOSFET 22 obtains a fast and stable gate drive signal. To obtain a fast and stable gate drive signal, drive unit 2 corresponds to the U, V, and W phases of the motor, and is evenly distributed in a 120-degree circle along the edge of substrate 1. An isolation trench is provided between the upper-bridge MOSFET 21 and the lower-bridge MOSFET 22 in each group of drive unit 2. This isolation trench is a copper-free channel excavated on the top layer of substrate 1, with a width of not less than 1.5 mm. This structure ensures that the U, V, and W phase power circuits are evenly distributed in space, reducing electromagnetic coupling between them. Simultaneously, the isolation trench effectively blocks surface leakage paths and arc risks between adjacent high-voltage nodes, improving interphase insulation performance and overall operational reliability. The source pad of the upper-bridge MOSFET 21 and the drain pad of the lower-bridge MOSFET 22 are directly connected through a wide copper strip 26 on the top layer of substrate 1. The width of the wide copper strip 26 is not less than 5 mm. This structure forms a low-impedance, large-section power current channel, significantly reducing the on-resistance and parasitic inductance of the main circuit during switching, effectively suppressing voltage overshoot and power loss, while also improving current carrying capacity and thermal stability.

[0016] Working principle: When using this controller circuit board, an external control signal is first input to the upper bridge drive group 23 and the lower bridge drive group 24. The first NPN transistor 231, PNP transistor 232, and second NPN transistor 233 in the upper bridge drive group 23 sequentially transmit drive signals. The third NPN transistor 241, second PNP transistor 242, and fourth NPN transistor 243 in the lower bridge drive group 24 collaboratively output drive levels. Subsequently, the upper bridge drive group 23 drives the gate of the upper bridge MOSFET 21, and the lower bridge drive group 24 drives the gate of the lower bridge MOSFET 22, causing the upper bridge MOSFET 21 and the lower bridge MOSFET 22 to conduct alternately in phase. When the circuit is turned off, current flows from the power supply through the drain of the upper bridge MOSFET 21 and out through the source, then through the wide copper strip 26 into the drain of the lower bridge MOSFET 22, and then back to ground through its source. This current path corresponds to one of the U, V, or W phases of the motor. The three sets of drive units 2 control the three-phase windings respectively, and each phase works independently. The isolation slot between the upper bridge MOSFET 21 and the lower bridge MOSFET 22 ensures electrical isolation between phases. The shared heat dissipation copper area 25 is connected to the inner layer ground plane of the substrate 1 through the thermal via 251, providing a unified heat conduction path for the upper bridge MOSFET 21 and the lower bridge MOSFET 22, thus completing the three-phase full-bridge drive control of the motor and completing a series of operations.

[0017] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A controller circuit board, comprising a substrate (1), characterized in that: The substrate (1) is provided with three sets of driving units (2) arranged in a triangular symmetrical manner. Each set of driving units (2) includes an upper bridge MOS transistor (21), a lower bridge MOS transistor (22), an upper bridge driving group (23), a lower bridge driving group (24), and a common heat dissipation copper area (25). The upper bridge MOS transistor (21) and the lower bridge MOS transistor (22) are symmetrically mounted along the longitudinal center line of the substrate (1). The upper bridge driving group (23) is located in the gate pin area of ​​the upper bridge MOS transistor (21), and the lower bridge driving group (24) is located in the gate pin area of ​​the lower bridge MOS transistor (22). The common heat dissipation copper area (25) is located directly below the drain pads of the upper bridge MOS transistor (21) and the lower bridge MOS transistor (22) and is in thermal contact with them.

2. The controller circuit board according to claim 1, characterized in that: The upper bridge drive group (23) is composed of a first NPN transistor (231), a PNP transistor (232), and a second NPN transistor (233) cascaded in sequence. The three are linearly distributed along the substrate (1) laterally, and the collector pad of the first NPN transistor (231) and the base pad of the PNP transistor (232) are directly connected through the top metal trace.

3. The controller circuit board according to claim 1, characterized in that: The lower bridge drive group (24) includes a third NPN transistor (241), a second PNP transistor (242) and a fourth NPN transistor (243). The third NPN transistor (241) and the second PNP transistor (242) share the same ground pad. The emitter pad of the fourth NPN transistor (243) is adjacent to the gate pad of the lower bridge MOS transistor (22) and the distance between them does not exceed 2 mm.

4. The controller circuit board according to claim 1, characterized in that: The common heat dissipation copper area (25) is a solid copper layer embedded in the top layer of the substrate (1), and the area of ​​the common heat dissipation copper area (25) covers the total projection area of ​​the drain pads of the upper bridge MOS transistor (21) and the lower bridge MOS transistor (22). The common heat dissipation copper area (25) extends downward to the two ground planes of the inner layer of the substrate (1), and the three copper layers are interconnected through multiple thermal vias (251).

5. The controller circuit board according to claim 1, characterized in that: The drive unit (2) corresponds to the three phases U, V and W of the motor and is evenly distributed in a 120-degree circle along the edge of the substrate (1). Each group of the drive unit (2) has an isolation groove between the upper bridge MOS transistor (21) and the lower bridge MOS transistor (22). The isolation groove is a copper-free channel excavated on the top layer of the substrate (1) with a width of not less than 1.5 mm.

6. The controller circuit board according to claim 1, characterized in that: The source pad of the upper bridge MOS transistor (21) and the drain pad of the lower bridge MOS transistor (22) are directly connected through a wide copper strip (26) on the top layer of the substrate (1), and the width of the wide copper strip (26) is not less than 5 mm.

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