
AS3515 V15
austriamicrosystems
Data Sheet, Confidential
www.austriamicrosystems.com
Revision 3.1
33
- 66
Table 33 CVDD trimming
CVDDp<1:0>
CVDD
0
Vnom (see )
0
1
Vnom – 50mV
1
0
Vnom - 100mV
1
Vnom - 150mV
This gives 0.85V to 1.8V as total range of the CVDD voltage.
Table 34 CVDD programming range
P_CVDD
CVDDp=11
CVDDp=10
CVDDp=01
CVDD=00
VSS
OFF
150k to VSS
0.85V
0.90V
0.95V
1.00V
Open
1.15V
1.10V
1.15V
1.20V
150k to DVDD
1.35V
1.40V
1.45V
1.50V
DVDD
1.65V
1.70V
1.75V
1.80V
Three different functional paths generate CVDD:
1.
Direct length regulation from VB1V
Mode1=true IF ((VNOM+Vmargin1) < VB1V < (VTH1)) && (NoUSB)
Vmargin1=50mV/150mV (100mV Hysteresis)
VTH1=1.7V/1.8V (100mV Hysteresis)
VBAT LDO is used when VB1V>(VNOM+50mV) because length reg. is a 1ohm device.
VBAT LDO is used when VB1V<(1.8V) since Mode1 is efficient just with single battery cell.
VBAT LDO is not used when there is high supply present from USB even when VB1V is in range.
(there is no dependency on CHARGER_IN needed because with a charger a 4V LiIo battery is used anyway)
2.
Direct length regulation from CPVDD
Mode2=true IF ((Not Mode1) && (CPVDD < (VNOM+Vmargin2)))
Vmargin2=200mV/300mV (100mV Hysteresis)
CPVDD LDO is used when VBAT LDO Mode1 is not entered and
CPVDD is not high enough to do 2:1 charge-pump regulation.
3.
Charge-Pump CPVDD division by 2 active plus length regulation
Mode3=true IF ((Not Mode1) && (Not Mode2))
ams
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