Panasonic EB-GD93, Техническое руководство

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POWER SUPPLIES
MCUK001001G8 Section 9 Issue 1
Technical Guide – 39 – Revision 0
9.5.3. Power On-Off Control
The hardware model for the Power On/Off Control and Power Source Failure functions can be expressed by the following
boolean expression and logic diagram.
On/Off = VBAT + ((nPOWKEY · RTC_INT · EXT_PWR) + nLVA_INT)
Figure 9.2: Power On / Off Control and Power Source Failure Logic Diagram
On/Off: Initially this active low signal is under Hardware control, the purposes of which are as follows:
1. Enable all voltage supplies to OMEGA (D28V, D28VB, A28V, D18VB & D18V).
2. Enable VSRF & VSVCXO voltage supplies to RF.
3. Generation of OSCAS Master Clock signal.
4. Set nRESET signal LOW.
5. Wait approximately 200 ms for the voltage output of the regulators and 13 MHz Clock to become stable. Allow reset of
HERCULES and OMEGA internal blocks.
6. Set nRESET HIGH causing the ARM processor to start from address 0.
9.5.4. Power Source Failure
The SIM card contains EEPROM. If the battery power fails while the SIM is active, the SIM may corrupt its memory as the power
supply drops out of specification.
The FIQ(nLVA) is a non-maskable interrupt generated by OMEGA and sent to the CPU which forces exception processing
whenever the main battery voltage drops below 2.7 V.
9.5.5. Voltage Regulation
The telephone has the following power sources:
DV28V: Baseband power supply for digital and analogue circuitry:
Provides the main power for the baseband digital part (Hercules, memories and LCD) and some analogue circuits.
Voltage: 2.9 V ±0.2 V
Current: 120 mA max.
Dropout: 150 mV max (max. load)
nLVA_INT
On/Off
nPOWKEY
nIGNITION
EXT_PWR
RTC_INT
VBAT
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