MIC280
Micrel
MIC280
12
May 2006
Conguration Locking
The security register, LOCK, provides the ability to disable
conguration changes as they apply to the MIC280s most
critical functions: shutdown mode, and reporting diode faults
and over-temperature events. LOCK provides a way to prevent
malicious or accidental changes to the MIC280 registers that
might prevent a system from responding properly to critical
events. Once L0, L1, or L2 has been set, the global interrupt
enable bit, IE, will be set and xed. It cannot subsequently be
cleared. Its state will be reected in the conguration register.
The bits in LOCK can only be set once. That is, once a bit is
set, it cannot be reset until the MIC280 is power-cycled or a
warm reset is performed by setting RST in the conguration
register. The warm reset function can be disabled by setting
L4 in LOCK. If L4 is set, locked settings cannot be changed
during operation and warm resets cannot be performed; only
a power-cycle will reset the locked state(s).
If L0 is set, the values of IM0 and CRIT0 become xed and
unchangeable. That is, writes to CRIT0 and the corresponding
interrupt enable bit are locked out. A local over-temperature
event will generate an interrupt regardless of the setting of
IE or its interrupt mask bit.
If L1 is set, the values of IM1 and CRIT1 become xed and
unchangeable. A remote over-temperature event will gener-
ate an interrupt regardless of the setting of IE or its interrupt
mask bit. Similarly, setting L2 will x the state of IM2, allow-
ing the system to permanently enable or disable diode fault
interrupts. A diode fault will generate an interrupt regardless
of the setting of IE or its interrupt mask bit.
L3 can be used to lock out shutdown mode. If L3 is set, the
MIC280 will not shut down under any circumstances. Attempts
to set the SHDN bit will be ignored and all chip functions will
remain operational. If L3 is set while the MIC280 is in shutdown
mode, it will immediately exit shutdown mode and resume
normal operation. It will not be possible to subsequently re-
enter shutdown mode.
Setting L4 disables the RST bit in the conguration register,
preventing the host from initiating a warm reset. Writes to
RST will be completely ignored if L4 is set.
LOCK BIT
FUNCTION LOCKED
RESPONSE WHEN SET
   L0
Local over-temperature detection
IM0 xed at 1, writes to CRIT0 locked-out; IE permanently set
    L1
Remote over-temperature detection
IM1 xed at 1; writes to CRIT1 locked-out; IE permanently set
    L2
Diode fault interrupts locked on or off
IM2 xed at current state; IE permanently set if IM2=1
    L3
Shutdown mode
SHDN xed at 0; exit shutdown if SHDN=1 when L3 is set
    L4
Warm resets
RST bit disabled; cannot initiate Warm resets
Table 7: Lock bit functionality
相关PDF资料
MIC2800-GFSYML TR IC REG TRPL BUCK/LINEAR 16MLF
MIC281-7BM6 TR IC SUPERVISOR THERMAL SOT23-6
MIC2810-1JGMYML TR IC REG TRPL BUCK/LINEAR 16MLF
MIC284-2BMM TR IC SUPERVISOR THERM 2ZONE 8-MSOP
MIC3385-1.5YHL TR IC REG DL BCK/LINEAR SYNC 14-MLF
MIC384-1YMM IC SUPERVISR THERM LOC/REM 8MSOP
MIC5158BN IC REG CTRLR SGL FIX/ADJ 14-DIP
MIC5159BM6 TR IC REG CTRLR SGL POS ADJ SOT23-6
相关代理商/技术参数
MIC280-7BM6TS 制造商:Rochester Electronics LLC 功能描述:- Bulk
MIC2807-JJYML TR 功能描述:PMIC 解决方案 PAM Power Management IC: DAC controlled DC-DC + 2 LDOs RoHS:否 制造商:Texas Instruments 安装风格:SMD/SMT 封装 / 箱体:QFN-24 封装:Reel
MIC2807-MMYML 制造商:Rochester Electronics LLC 功能描述: 制造商:RF Micro Devices Inc 功能描述: 制造商:Micrel Inc 功能描述:
MIC2807-MMYML TR 功能描述:PMIC 解决方案 PAM Power Management IC: DAC controlled DC-DC + 2 LDOs RoHS:否 制造商:Texas Instruments 安装风格:SMD/SMT 封装 / 箱体:QFN-24 封装:Reel
MIC2807-MMYML-TR 功能描述:RF IC PA Management IC CDMA2000, UMTS/WCDMA 2MHz W/DAC Input and Bypass Switch 17-MLF? (2.5x2.8) 制造商:microchip technology 系列:- 包装:剪切带(CT) 零件状态:有效 功能:PA 管理 IC 频率:2MHz RF 类型:CDMA2000,UMTS/WCDMA 辅助属性:W/DAC 输入和旁路开关 封装/外壳:17-VFQFN,17-MLF? 供应商器件封装:17-MLF?(2.5x2.8) 标准包装:1
MIC2807-NGYML 制造商:RF Micro Devices Inc 功能描述:
MIC2807-NNYML 制造商:Rochester Electronics LLC 功能描述: 制造商:RF Micro Devices Inc 功能描述:
MIC2807-NNYML TR 功能描述:PMIC 解决方案 PAM Power Management IC: DAC controlled DC-DC + 2 LDOs RoHS:否 制造商:Texas Instruments 安装风格:SMD/SMT 封装 / 箱体:QFN-24 封装:Reel