WM8351CGEB/RV WOLFSON [Wolfson Microelectronics plc], WM8351CGEB/RV Datasheet - Page 106

• Manufacturer Part Number: WM8351CGEB/RV
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

WM8351
w
Figure 64 WM8351 Operating State Diagram
14.2.1
The WM8351 moves from the ACTIVE to the HIBERNATE state when the HIBERNATE register bit is
set. It can also move to hibernate using the Hibernate Edge or the Hibernate Level function from the
GPIOs.
It returns to the ACTIVE state when the Hibernate Level GPIO function is reset and the HIBERNATE
bit is set to 0. It can also return to ACTIVE via the Hibernate Edge function or when a wake-up event
(see Section 14.3.1) occurs.
If a fault condition occurs in the HIBERNATE state, the WM8351 moves to the OFF state.
Table 55 Invoking HIBERNATE State
The behaviour of the WM8351 in the HIBERNATE state is programmable in terms of supply voltage
generation, interrupts and resets. Fast battery charging is disabled in the HIBERNATE state, but
trickle charging is possible.
R5 (05h)
System
Hibernate
ADDRESS
LINE < shutdown threshold
LINE < (VRTC + 50mV)
VRTC > POR threshold
HIBERNATE STATE SELECTION
OR clock failure
AND LINE > startup threshold
(from any state)
(from any state)
LINE > UVLO level
BIT
15
ON event
HIBERNATE
LABEL
sequencing
pre-active
BACKUP
startup
ZERO
OFF
Startup
Fault
DEFAULT
0
LINE < UVLO level
VRTC < POR threshold
ACTIVE
OFF event
ON event
Determines what state the chip should
operate in.
0 = Active state
1 = Hibernate state
The register bit defaults to 0 when a reset
happens
HIBERNATE=1
in R5
HIBERNATE
DESCRIPTION
PD, April 2012, Rev 4.5
Production Data
106