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53
TD_Repair_L2.5_A70_A75_R1.0.pdf Release
1.0
Mode Pin
Requirements
Description
Active Mode
(submode of Full
operating mode)
In this mode, the uC controls the charging block and most of
the failure cases. The ASIC can be controlled by the TWI
interface, interrupts can be sent by the ASIC. Further, the
temperature and the voltages are supervised (in case of
failure, the uC will be informed). In case of watchdog failure,
overvoltage or power on reset, the ASIC will be switched off
immediately. The mono and stereo audio block can be
switched on in active mode.
Sleep Mode with
special low
current
operating mode
for the LDOs
(submode of Full
operating mode)
SLEEP1_N
TC_ON
CHARGE_uC
A low level at the pin SLEEP1_N will switch the phone from
the mode “PHONE ON” to sleep mode. This mode can be
activated out of the active mode. In sleep mode trickle charge
(TC_ON), fast charge (CHARGE_UC), supply overvoltage
detection, supply undervoltage detection, audio function are
switched off. LDO undervoltage detection, clock and all
reference voltages are active. LDOs are working in low current
mode. The possibility to supply the ASIC from VDD_CHARGE
with the internal LDO is switched off. Only the battery can be
used for supply. This mode is called “phone stand-by”.
Trickle charge
mode to be able
to support
charging of the
battery
VDD_CHARGE
EXT_PWR
In case of a rising edge at VDD_CHARGE the ASIC goes
from power down to interim mode. In this mode, the oscillator
and the reference are started. The fuses are read in. If the
voltage is high enough (after a delay time of 1 ms to filter a
ringing), the signal EXT_PWR is going to H and the power up
continues. The ASIC shuts off if the voltage is below
threshold. In Trickle Charge Mode, first the charge unit starts
and charges the battery in case of undervoltage. After
reaching this threshold voltage or if the battery has enough
voltage from the beginning, a start up similar to the regular
startup mode is initiated. In case of voltage drop under battery
threshold, the first trickle charging can be started again until
the Active Mode is entered. In this case, the internal VDDREF
regulator, the reference generator and oscillator are started
and the ASIC is supplied by VDDREF. If any failure is
detected, the ASIC is switched off.
