lp8765rlx National Semiconductor Corporation, lp8765rlx Datasheet - Page 6

• Manufacturer Part Number: lp8765rlx
• Description: High Performance Power Management Unit For Handset Applications
• Manufacturer: National Semiconductor Corporation

www.national.com
Device Operation Description
OPERATION MODES
POWER-ON-RESET: In POWER-ON RESET mode all internal registers are reset to the default values.
STANDBY:
START UP:
IDLE:
SLEEP:
SHUTDOWN:
SYSTEM RESET:
A:
DI/O:
G:
Pin #
A5
A4
Analog Pin
Digital Input/Output Pin
Ground
XOUT
Name
XIN
In STANDBY mode all PMU functions are disabled except BB charger, 32 KHz OSC & RTC.
Startup sequence is triggered by setting Power-on-Switch (PWR_ON) high for 100 ms or connecting a
suitable voltage to charger input (VIN_CHG). For RTC ALARM events the startup sequence begins after
2ms delay from the RTC events. During the startup sequence, the 2.5V reference voltage will be powered
by either charger block or battery first in order to detect battery existing. If there is a battery and the battery
voltage is over OPVM, then the default on regulators (Buck1, Buck2 & LDO5) will be enabled according to
a pre-programmed timing pattern. If the regulators are enabled, RSTOUT_N is released, allowing the pro-
cessor to start up. PS_HOLD must be set high within a programmed timer* (8s max) from the start of
STARTUP state; this is true for all startup events except PWR_ON. For PWR_ON startup, PMU stays in
POWER ON state when PWR_ON is held high, and the PS_HOLD must be set high before the PWR_ON
goes low or Power-on-Switch is released. Otherwise, PMU will go to SHUTDOWN state.
If there is no main battery detected (voltage at ADC1 pin is about 2.4V), PMU will not start the startup
sequence. In other modes, the PMU will not enable the charger. If the main battery is removed when
PMU is running, then Charger will be disabled immediately to force UVLO shutdown.
If two-pin battery is used then ADC1 pin should be connect to GND through a resistor or floating in
order to start up the PMU normally. However, there will be no battery exiting detection.
PMU will enter into IDLE mode (normal operating mode) after PS_HOLD signal is asserted by the host
processor. IDLE mode will enable all PMU functions that can be controlled by the Serial Interface or direct
control inputs. PS_HOLD going low for 10 ms, VDD voltage below UVLO, Chip temperature over TSDH,
or a flag failure in a monitored regulator (LDO5) for 10 ms will initiate a SHUTDOWN Sequence.
When BB pulls SLEEP_N pin LOW, the PMU will not do anything except setting BUCKs and LDOs to low-
power mode in order to minimize quiescent current if LDOs_LOW_PWR_IN_SLEEP and
BUCKs_LOW_PWR_IN_SLEEP bits are set to 1, otherwise both BUCKs and LDOs will stay in normally
mode. However, in low-power mode, the summary of total load current of BUCKs or LDOs should stay
below 5mA. Buck1 has two preset voltages (BUCK1 NORMAL & BUCK1 SLEEP); BUCK1 output equals
BUCK1 SLEEP when SLEEP_N pin is low, and goes back to BUCK1 NORMAL when SLEEP_N is high.
By default, BUCK1 SLEEP & NORMAL are same 1.2V. In this mode, only LDO1, LDO2, LDO3, LDO4 and
LDO9 can be enabled/disabled through GPIO pins (EN1,2&3). If I
sleep, then for other power regulators, BB need to turn them off through I
Otherwise, these power regulators will stay on during BB sleep. The condition of going to SHUTDOWN
state is the same as in IDLE state. Please see Register Maps for detail.
In this state, RSTOUT_N is pulled low, and all regulators are disabled according to pre-programmed timing
pattern (opposite of STARTUP sequence). After this, all registers are reset to default values except address
xxxx, then PMU will go to STANDBY state.
PMU goes to SYSTEM RESET mode if RSTIN_N input has been pulled low for xxms**. There are two
different reset methods:
1. Cold reset (EN_RSTIN_SHUTDOWN = high); PMU will go to SHUTDOWN state first and then initiate
STARTUP event automatically. PS_HOLD must be high within programmed PS_HOLD timer, otherwise
PMU will go to SHUTDOWN state.
ms);
2. Hot reset (EN_RSTIN_SHUTDOWN = low); PMU will pull low RSTOUT_N and disable all the power
regulators except BUCK1, BUCK2, LDO5(DLDO1), REF_OUT. A STARTUP event then initiates automat-
ically, and PS_HOLD must be high within programmed PS_HOLD timer, otherwise PMU will go to
SHUTDOWN state.
a. Enable shutdown and enter EPROM READ + PREPARE mode, active the pulldown (Total time = 33
b. Disable the pulldown and enter STARTUP mode;
c. Wait 100 ms; and
d. Enter Normal working mode.
Type
A
A
External crystal oscillator IN
External crystal oscillator OUT
D:
O:
Digital Pin
Output Pin
6
Description
I:
P:
2
C communication is disabled during
2
C before SLEEP_N goes to 0.
Input Pin
Power Pin