During power on, the Brownout reset (BOR) keeps the device under reset until the supply voltage reaches the specified VBOR threshold. VBOR is configured through device option bytes. By default, BOR is off. 4 programmable VBOR thresholds can be selected. ● BOR off (VBOR0): reset threshold level for 1.8 to 2.10 V voltage range ● BOR Level 1 (VBOR1): reset threshold level for 2.10 to 2.40 V voltage range ● BOR Level 2 (VBOR2): reset threshold level for 2.40 to 2.70 V voltage range ● BOR Level 3 (VBOR3): reset threshold level for 2.70 to 3.60 V voltage range When the supply voltage (VDD) drops below the selected VBOR threshold, a device reset is generated.