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6.4.3 Reset :- ILBRST / UVLO2
The MiniMoe generates a reset pulse (active low) to the NELL (#L4 -ILBRST) when
it detects that the battery voltage is below the UVLO2 threshold of (2.85V- 3.1V).
The device also disables internal regulators R2, R3, R5, R6, and R7, this then
holds the ILB in reset mode, allowing only the real time clock to run. When the
battery is recharged or replaced the ILB reset pulse is reversed and the
regulator's re-activated.
There is another under volt lock off point (UVLO1) which is activated when the
battery voltage reaches the range of between (2.6V-2.85V). This then disables
regulator 1 (ILB/RTC regulator) and via the output pin (BUB-#12) drives the
external FET TR25, which switches ILB/RTC supply over to the back-up battery
BATT1.
6.4.4 Power Control
The ILB section of NELL performs the power control management of the HHP. It is
this power control management that enables the HHP to execute its power saving
functions. The ILB runs the 32kHz clock and controls the transition of the HHP
between various power modes.
The ILB controls the power mode(s) of the HHP via two signals:
1. +RG3VPWR
This connects to MiniMoe (IC19) #21 (EN3). A high on this pin switches
regulator 3 (+3VSC) on thus powering IC27and the SRAM (IC9).
A low switches it off.
2. HARD_PWR
This connects to MiniMoe #28 (EN2). A high on this pin switches regulator
2 (+3VNELL) on thus powering the NELL (IC8), the flash ROM (IC15), and the
EEPROM (IC10). A low switches it off and powers down NELL etc.
3. SIMPWR (NELL#L5)
This output from NELL connects to MiniMoe (IC19) #20. A logic high switches
The output SIMVCC (#1) to on, and supplies power to the SIM connector(#6).
4. SIMVSEL (SIM Voltage Select) (NELL#L3)
This output from NELL connects to MiniMoe #18. A logic high on this pin
selects the SIMVCC supply voltage to either 3v or 5v.
5. +5VRFON
This output from NELL connects to MiniMoe #19. A logic high on this pin
switches the output +5VRF on and is then fed to the RF board.
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