WM8351CGEB/RV WOLFSON [Wolfson Microelectronics plc], WM8351CGEB/RV Datasheet - Page 167
WM8351CGEB/RV
Manufacturer Part Number
WM8351CGEB/RV
Description
Manufacturer
WOLFSON [Wolfson Microelectronics plc]
Datasheet
1.WM8351CGEBRV.pdf
(330 pages)
- Current page: 167 of 330
- Download datasheet (4Mb)
Production Data
18 SYSTEM MONITORING AND UNDERVOLTAGE LOCKOUT (UVLO)
w
The WM8351 includes several mechanisms to prevent the system from starting up, or force it to shut
down, when power sources are critically low.
The under-voltage lockout (UVLO) is a non-programmable voltage limit. When the available supplies
are below this limit, the WM8351 enters the BACKUP state. The WM8351 can only proceed from
BACKUP to the OFF state if LINE is above the UVLO level. Whenever the WM8351 is in ACTIVE,
HIBERNATE or OFF state and LINE falls below the UVLO level, the WM8351 returns to the BACKUP
state.
The UVLO limit threshold is equal to VRTC + 50mV. The precise value of VRTC may vary between
devices, within the limits defined in the Electrical Characteristics (see Section 7.5).
The startup threshold is a programmable voltage limit. The WM8351 can only proceed from OFF to
the ACTIVE state if LINE is above the startup threshold. (Note that, in the case of USB-powered
operation, there are additional voltage requirements; see Section 17.4.). The startup threshold is
determined by the PCCMP_ON_THR register field.
The shutdown threshold is determined by the PCCMP_OFF_THR register field. When LINE falls
below this threshold, the WM8351 raises a SYS_HYST_COMP_FAIL_EINT interrupt. In addition, the
WM8351 takes the action set by PCCOMP_ERRACT. If this bit is set, then the WM8351 will shut
down in response to the LINE voltage falling below the shutdown threshold.
The startup and shutdown control register fields are described in Table 112. Note that the startup
threshold should always be set higher than the shutdown threshold in order to create a hysteresis,
making the system more stable.
The SYS_HYST_COMP_FAIL_EINT interrupt is one of the second-level interrupts which triggers a
first-level System Interrupt, SYS_INT (see Section 24). This can be masked by setting the mask bit as
described in Table 113.
Table 112 Battery Monitoring and UVLO Control
R179 (B3h)
Power Check
Comparator
ADDRESS
BIT
6:4
2:0
14
PCCMP_ER
RACT
PCCMP_OF
F_THR [2:0]
PCCMP_ON
_THR [2:0]
LABEL
DEFAULT
010
101
0
Action to take when LINE falls below
PCCMP_OFF_THR level (as well as
generating an interrupt)
0 = ignore
1 = shut down system
Power check comparator system shutdown
threshold value
000 = 2.9V
001 = 3.0V
…
111 = 3.6V
Protected by security key.
Power check comparator system startup
threshold value
000 = 2.9V
001 = 3.0V
…
111 = 3.6V
Protected by security key.
DESCRIPTION
PD, April 2012, Rev 4.5
WM8351
167
Related parts for WM8351CGEB/RV
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
WM9701ALow Power AC97 Multimedia Audio Codec
Manufacturer:
WOLFSON Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
WM8973LGEFLSTEREO CODEC FOR PORTABLE AUDIO APPLICATIONS
Manufacturer:
WOLFSON Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Wolfson Audioplus? Stereo Codec With Power Management
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Wolfson Audioplus? Stereo Codec With Power Management
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Wolfson Audioplus? Stereo Codec With Power Management
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Handset Receiver Speaker Driver With Wolfson Myzone Ambient Noise Cancellation
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Stereo Headphone Driver With Wolfson Myzonetm Ambient Noise Cancellation
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Wolfson Audioplustm Hi-fi Audio Codec And Power Management Unit For Mobile Multimedia
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Mono CODEC with Speaker Driver and Video Buffer
Manufacturer:
WOLFSON [Wolfson Microelectronics plc]
Datasheet:
Part Number:
Description:
Stereo ADC with Microphone Input and Clock Generator
Manufacturer:
WOLFSON [Wolfson Microelectronics plc]
Datasheet:
Part Number:
Description:
WM9701ALow Power AC97 Multimedia Audio Codec
Manufacturer:
WOLFSON Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
WM8973LGEFLSTEREO CODEC FOR PORTABLE AUDIO APPLICATIONS
Manufacturer:
WOLFSON Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Manufacturer:
Wolfson Microelectronics plc
Datasheet:
Part Number:
Description:
Manufacturer:
Wolfson Microelectronics plc
Datasheet: