DocID027559 Rev 1

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AN4661

Power supplies

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Figure 1. Power supply scheme

1. Optional. If a separate, external reference voltage is connected on VREF+, the two capacitors (100 nF and

1 μF) must be connected.

2. VREF+ is either connected to VREF+ or to VDDA (depending on package).

3. VREF- is either connected to VREF- or to VSSA (depending on package).

4. 19 is the number of VDD and VSS inputs.

5. Refer to Section 1.3.7: Regulator ON/OFF and internal reset ON/OFF availability to connect

BYPASS_REG and PDR_ON pins.