User`s guide

Rev. 1.10 128 November 14, 2014 Rev. 1.10 129 November 14, 2014
HT66FW2230
Wireless Charger A/D Flash 8-Bit MCU
Low Voltage Detector – LVD
ThedevicehasaLowVoltageDetectorfunction,alsoknownasLVD.Thisenablesthedeviceto
monitorthepowersupplyvoltage,V
DD
,andprovidesawarningsignalshoulditfallbelowacertain
level.Thisfunctionmaybeespeciallyusefulinbatteryapplicationswherethesupplyvoltagewill
graduallyreduceasthebatteryages,asitallowsanearlywarningbatterylowsignaltobegenerated.
TheLowVoltageDetectoralsohasthecapabilityofgeneratinganinterruptsignal.
LVD Register
TheLowVoltageDetectorfunctioniscontrolledusingasingleregisterwiththenameLVDC.Three
bitsinthisregister,VLVD2~VLVD0, areusedtoselectoneofeightxedvoltagesbelowwhich
alowvoltageconditionwillbedetermined.AlowvoltageconditionisindicatedwhentheLVDO
bitisset.IftheLVDObitislow,thisindicatesthattheV
DD
voltageisabovethepresetlowvoltage
value.TheLVDENbitisusedtocontroltheoverallon/offfunctionofthelowvoltagedetector.
Settingthebithighwillenablethelowvoltagedetector.Clearingthebittozerowillswitchoffthe
internallowvoltagedetectorcircuits.Asthelowvoltagedetectorwillconsumeacertainamountof
power,itmaybedesirabletoswitchoffthecircuitwhennotinuse,animportantconsiderationin
powersensitivebatterypoweredapplications.
LVDC Register
Bit 7 6 5 4 3 2 1 0
Name — — LVDO LVDEN — VLVD2 VLVD1 VLVD0
R/W — — R R/W — R/W R/W R/W
POR — — 0 0 — 0 0 0
Bit7~6 Unimplemented,readas"0"
Bit5 LVDO:LVDOutputFlag
0:NoLowVoltageDetect
1:LowVoltageDetect
Bit4 LVDEN:LowVoltageDetectorControl
0:Disable
1:Enable
Bit3 Unimplemented,readas"0"
Bit2~0 VLVD2 ~ VLVD0:SelectLVDVoltage
000:2.0V
001:2.2V
010:2.4V
011:2.7V
100:3.0V
101:3.3V
110:3.6V
111:4.0V