Panasonic EBX70 - CELL PHONE, Service Manual

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TECHNICAL DESCRIPTION
PMCD030901C8 Section 4 Issue 1
Service Manual – 23 – Revision 0
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VRUSB:
not used.
4.8.6 Regulator Sleep Function
To reduce power consumption in the analogue section of the baseband chipset, the voltage regulators can be placed in a low
power mode or disabled by the processor when it enters a low activity sleep mode. During sleep mode, VRABB, and VRDBB,
VRIO, VRMEM, VRRAM and VRSIM are switched to low power mode.
4.8.7 Battery Charging and Monitoring
The status of the LCD battery icon is determined by the value of BAT_VOLT returned from the SYREN MADC, as indicated in
the table:
Two types of external charging accessories are available for the handset - a switching type AC Adaptor and a DC Adaptor.
Battery charging is controlled by the CPU within the phone. If external power is detected and the temperature is within
specified limits, the charger starts the rapid charge algorithm. Battery charge termination for the Li-On battery is reached
when the charging current in constant voltage mode reaches 50 mA. Charging is aborted if the current is greater than 800 mA
or the battery voltage rises above 4.25 V.
Deeply-Discharged Batteries
In the case of deeply discharged batteries, there may not be enough power in the battery to initiate charging. In this case, the
charging circuit automatically starts to trickle charge the battery until there is enough power to switch on the phone. LED
indication will be provided to the user even though the handset is not active.
The LED will switch off when charging is complete. The time to reach the fast charge state is dependent on the trickle charge
current (approximately 46 mA at VBAT = 2.5 V) but is specified as less than 16 minutes worst case.
Over Voltage Protection
As the accessory connector is unique to Panasonic, only approved chargers can be used with the handset. Therefore, no
additional circuitry is required within the handset to prevent the charger voltage exceeding the design limit of 20 V.
Voltage 3.3 V ±0.2 V
Current 15 mA max.
Dropout 100 mV max (load max)
Supply USB_VBUS (5V +0.5 V, -1 V
Icon Status Battery Capacity
Battery Voltage Battery Voltage
(In Call) (Standby)
3 bar 100% to 50% 3.77 V < 3.83 V <
2 bar 50% to 20% 3.68 V < < 3.77 V 3.74 V < < 3.83 V
1 bar 20% to 0% 3.40 V < < 3.68 V 3.46 V < < 3.74 V
Low Voltage Alarm 0% < 3.40 V < 3.46 V
Input Output
Voltage Voltage Current
AC Adaptor 100 - 240 V 5.8 V ±0.2 V 650 mA ± 100 mA
DC Adaptor 5.8 V ±0.2 V 700 mA ± 30 mA