
preliminary
preliminary
iC-PVS
LINEAR/OFF-AXIS
BATTERY-BUFFERED ABSOLUTE POSITION HALL SENSOR
Rev A2, Page 19/51
DEVICE OPERATING STATES
This chapter describes the first steps for startup of
iC-PVS and the different operating states.
Initial Startup and Power-On-Reset
iC-PVS has two supply voltage inputs named VDD and
VBAT. Both refer to the same ground point at pin GND.
The system is powered via the VDD pin as long as the
applied voltage exceeds the V
on
threshold. The current
internal supply voltage can be measured at pin VDDS
which is used for further buffering with a bypass capaci-
tor. More information on the iC-PVS power scheme can
be found in chapter Supply Switch and Monitoring on
page 29.
In a common initial startup procedure the battery is con-
nected to the system via pin VBAT first. A power-on-re-
set is performed when rising the voltage at VBAT above
the power-on-reset threshold (Elec. Char. 401). This
puts all circuitry to a defined init state.
Note:
The power-on-reset voltage threshold is no sufficient
working condition. The device will only be bootable
and utilizable if VDD is risen above V
on
(see Figure
If battery backup is not used, it is necessary to tie pins
VBAT and VDD together. Pin VBAT must not be left
open. The permissible voltage range of VBAT is noted
in Elec. Char. 004.
As a second step the supply voltage is provided (VDD >
V
on
). This either happens shortly after battery insertion
or after a longer shelf life. iC-PVS will now progress
through the operating states described in Figure 12.
BOOT_ST
Read external
EEPROM
BATTERY_ST
Absolute engine
active only
NOMAG_ST
NOMAG_L = 1
(latched)
reduced absolute mode
ACTIVE_ST
Absolute
engine active
Sleep
RESET_ST
System halt
Power-On-Reset
Pin Preset
SLEEP_ST
Absolute
engine disabled
Reboot CMD
VDD > V
on
VDD < V
off
AMPL_ERR = 1
OR
POS_ERR = 1
AMPL_ERR = 1
OR
POS_ERR = 1
AMPL_ERR = 0
AND
POS_ERR = 0
(VDD < V
off
)
AMPL_ERR = 0
AND
POS_ERR = 0
(VDD > V
on
)
Sleep CMD
Sleep CMD
Restart CMD
STUP_ERR = 0
CFG_ERR = 0
CTR_ERR = 0
VDD > V
on
Figure 12: State diagram for device startup