BEHAVIOR AT POWER UP AND POWER DOWN FAIL-SAFE O" />
參數(shù)資料
型號(hào): MCZ33905BD5EK
廠商: Freescale Semiconductor
文件頁數(shù): 54/106頁
文件大?。?/td> 0K
描述: IC SBC CAN HS 5.0V 54SOIC
標(biāo)準(zhǔn)包裝: 26
應(yīng)用: 系統(tǒng)基礎(chǔ)芯片
接口: CAN,LIN
電源電壓: 5.5 V ~ 28 V
封裝/外殼: 54-SSOP(0.295",7.50mm 寬)裸露焊盤
供應(yīng)商設(shè)備封裝: 54-SOICW-EP
包裝: 管件
安裝類型: 表面貼裝
Analog Integrated Circuit Device Data
Freescale Semiconductor
51
33903/4/5
FAIL-SAFE OPERATION
BEHAVIOR AT POWER UP AND POWER DOWN
FAIL-SAFE OPERATION
OVERVIEW
Fail-safe mode is entered when specific fail conditions
occur. The “Safe state” condition is defined by the resistor
connected at the DGB pin. Safe mode is entered after
additional event or conditions are met: time out for CAN
communication and state at I/O-1 pin.
Exiting the safe state is always possible by a Wake-up
event: in the safe state, the device can automatically be
awakened by CAN and I/O (if configured as inputs). Upon
Wake-up, the device operation is resumed: enter in Reset
mode.
FAIL-SAFE FUNCTIONALITY
Upon dedicated event or issue detected at a device pin
(i.e. RST short to VDD), the Safe mode can be entered. In
this mode, the SAFE pin is active low.
Description
Upon activation of the SAFE pin, and if the failure
condition that make the SAFE pin activated have not
recovered, the device can help to reduce ECU consumption,
assuming that the MCU is not able to set the whole ECU in LP
mode. Two main cases are available:
Mode A
Upon SAFE activation, the MCU remains powered (VDD
stays ON), until the failure condition recovers (i.e. S/W is able
to properly control the device and properly refresh the
watchdog).
Modes B1, B2 and B3
Upon SAFE activation, the system continues to monitor
external event, and disable the MCU supply (turn VDD OFF).
The external events monitored are: CAN traffic, I/O-1 low
level or both of them. 3 sub cases exist, B1, B2 and B3.
Note: no CAN traffic indicates that the ECU of the vehicle
are no longer active, thus that the car is being parked and
stopped. The I/O low level detection can also indicate that the
vehicle is being shutdown, if the I/O-1 pin is connected for
instance to a switched battery signal (ignition key on/off
signal).
The selection of the monitored events is done by
hardware, via the resistor connected at DBG pin, but can be
over written by software, via a specific SPI command.
By default, after power up the device detect the resistor
value at DBG pin (upon transition from INIT to Normal mode),
and, if no specific SPI command related to Debug resistor
change is send, operates according to the detected resistor.
The INIT MISC register allow you to verify and change the
device behavior, to either confirm or change the hardware
selected behavior. Device will then operate according to the
SAFE mode configured by the SPI.
Table 9 illustrates the complete options available:
Exit of Safe Mode
Exit of the safe state with VDD OFF is always possible by
a Wake-up event: in this safe state the device can
automatically awakened by CAN and I/O (if I/O Wake-up was
enable by the SPI prior to enter into SAFE mode). Upon
Wake-up, the device operation is resumed, and device enters
in Reset mode. The SAFE pin remains active, until there is a
proper read and clear of the SPI flags reporting the SAFE
conditions.
Table 9. Fail-safe Options
Resistor at
DBG pin
SPI coding - register INIT MISC bits [2,1,0]
(higher priority that Resistor coding)
Safe mode
code
VDD status
<6.0 k
bits [2,1,0) = [111]: verification enable: resistor at DBG pin is typically
0 kohm (RA) - Selection of SAFE mode A
A
remains ON
typically 15 k bits [2,1,0) = [110]: verification enable: resistor at DBG pin is typically
15 kohm (RB1) - Selection of SAFE mode B1
B1
Turn OFF 8.0 s after CAN traffic bus idle detection.
typically 33 k bits [2,1,0) = [101]: verification enable: resistor at DBG pin is typically
33 kohm (RB2 - Selection of SAFE mode B2
B2
Turn OFF when I/O-1 low level detected.
typically 68 k bits [2,1,0) = [100]: verification enable: resistor at DBG pin is typically
68 kohm (RB3) - Selection of SAFE mode B3
B3
Turn OFF 8.0 s after CAN traffic bus idle detection
AND when I/O-1 low level detected.
相關(guān)PDF資料
PDF描述
NCN8024DWR2G IC SMART CARD IC2 28SOIC
TSI148-133IL IC PCI-VME BRIDGE 456PBGA
IDTTSI148-133ILY IC PCI/X TO VMEBUS BRIDGE
1604050-5 350A HOUSING SUB-ASSY,BLUE
1604037-1 CONN HOUSING 2-POLE 175AMP YEL
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MCZ33905BD5EKR2 功能描述:CAN 接口集成電路 5.0V SBC HSCAN DUAL LIN RoHS:否 制造商:Texas Instruments 類型:Transceivers 工作電源電壓:5 V 電源電流: 工作溫度范圍:- 40 C to + 85 C 封裝 / 箱體:SOIC-8 封裝:Tube
MCZ33905BD5R2 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:SBC Gen2 with CAN High Speed and LIN Interface
MCZ33905BS3EK 功能描述:CAN 接口集成電路 3.3V SBC HSCAN SNGL LIN RoHS:否 制造商:Texas Instruments 類型:Transceivers 工作電源電壓:5 V 電源電流: 工作溫度范圍:- 40 C to + 85 C 封裝 / 箱體:SOIC-8 封裝:Tube
MCZ33905BS3EKR2 功能描述:CAN 接口集成電路 3.3V SBC HSCAN SNGL LIN RoHS:否 制造商:Texas Instruments 類型:Transceivers 工作電源電壓:5 V 電源電流: 工作溫度范圍:- 40 C to + 85 C 封裝 / 箱體:SOIC-8 封裝:Tube
MCZ33905BS3R2 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:SBC Gen2 with CAN High Speed and LIN Interface