±12v insulated power reference board specialized for PLC and FA equipment
Devices connected to programmable logic controllers (PLCs) and factory automation (FA) fieldbus systems are equipped with analog signal processing circuits for sensors. These analog signal processing circuits require high precision and require a plus / minus insulated power supply for reliability reasons to prevent unexpected failures at sensor nodes from spreading to the entire system.
Transformer is a barrier to insulated power supply design
For high precision analog circuits, the GND must be turned off to prevent noise and improve reliability, so an insulated power supply is required.
Here, the choice of transformer is a barrier to insulated power design. In general, even if an IC for an insulated power supply is selected, it is necessary to develop a transformer that meets the power supply specifications.
As for the design of the transformer, the design rarely works in 1 single time, so it is common to give up the in-house production of the insulation power supply and outsource it to a power supply module specialized manufacturer.
IC for insulated power supply with low design hurdle
Analog Devices's unique voltage control scheme increases the flexibility of transformer selection. Below table shows an example of a transformer listed as a recommended component in the LT8302 data sheet.
It is available as a general-purpose part, not a custom product.
In addition, the built-in power FET greatly reduces the design difficulty.
| TRANSFORMER PART NUMBER | DIMENSIONS (W × L × H) (mm) | VENDOR | VIN (V) | VOUT (V) | IOUT (A) |
|---|---|---|---|---|---|
| 750311625 | 17.75 × 13.46 × 12.70 | Würth Elektronik | 8 to 32 | 3.3 | 2.1 |
| 750311564 | 17.75 × 13.46 × 12.70 | Würth Elektronik | 8 to 32 | 5 | 1.5 |
| 750313441 | 15.24 × 13.34 x 11.43 | Würth Elektronik | 8 to 32 | 5 | 1.3 |
| 750311624 | 17.75 × 13.46 × 12.70 | Würth Elektronik | 8 to 32 | 8 | 0.9 |
| 750313445 | 15.24 × 13.34 × 11.43 | Würth Elektronik | 8 to 36 | 24 | 0.3 |
| 750313460 | 15.24 × 13.34 × 11.43 | Würth Elektronik | 4 to 18 | 5 | 0.9 |
| 750313443 | 15.24 × 13.34 × 11.43 | Würth Elektronik | 8 to 36 | ±12 | 0.4 |
±12V insulated power reference board
We have recently developed the ± 12V Isolated Power Supply Reference Board, which is Macnica's original and specialized for PLC and FA equipment. This board is recommended for PLC and FA equipment designers who need a power supply reference board that converts ± 12V switching isolated output to ± 10V with a positive and negative LDO.
Image: ±12V Insulation Power supply circuit diagram and reference board