AN2871

Supply pins and decoupling

Doc ID 15304 Rev 3

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4.1.4

Summary

Figure 8 summarizes the SPC560Pxx device decoupling requirements (please refer to

Table 7 for descriptions of the supply/ground reference lines).

Figure 8.

Pin supply circuits

1.

The microcontroller can have more than one pin of this type. A couple of capacitors must be placed close to

each pin as shown in this diagram.

2.

The microcontroller can have more than one pin of this type. A 10 uF capacitors must be placed close to each pin

3.

The capacitor is only one. These capacitors on VDD_HV_AD pin can be also not close to the associated

pins.

4.

The recommended decoupling/stability capacitors can vary based on specific chosen ballast or circuitry.

See the device datasheet to choose the best recommended values For more information on SPC560Pxx

reset, please refer to the device reference manual.

a.

For the following list of devices:

-SPC560P34xx/P40xx cut1.1 and older

-SPC560P50xx/P44xx cut3.4 and older

-SPC560P60xx/P54xx

-SPC56AP60xx/AP54xx

It is not enough to be inside TVDD parameter range. it is needed on VDD_HV_REG pin a monotonic ramp up to 5V

or 3.3V starting from zero. To make the power up of the device more robust put a resistive network between

VDD_HV_REG, VDD_LV_REG and GND (see AN4057 for more details)