型号:MC68HC908JB8JDWE
厂家:FREESCALE
批号:年份
封装:SOP20
数量:25108
描述:现货,原厂进口全新原装,假一赔十!
MC68HC908JB8JDWE
MC68HC908JB8JDWE
Power-Up from LVR SE115-PowerDescriptionA few devices start abnormally during power-up. The issue is the release of the low voltage reset (LVR)earlier than the VREG reaching the CMOS logic operating voltage (typical 0.65 V).The LVR takes the VDD but not the VREG as a reference. LVR exists until the VDD reaches the LVRthreshold voltage (VLVR). The problem happens in few devices when the VDDrises quickly and the VREGrises slowly. If the LVR has been released but the VREGdoesn’t reach the CMOS logic operating voltage,the LVR does not have any effect. This might cause the internal logic to improperly initialize and the MCUmight not start normally.Therefore, the VDD voltage must be lower than the VLVR minimum (2.8 V) when the VREG voltagereaches the CMOS logic operating voltage.WorkaroundTo fix the problem, add a 10 Ω series resistor between the power supply and the VDD, and place a 10 μFcapacitor at the VDD pin and a 4.7 μF capacitor at the VREG pin