参数资料
型号: 4021-DKDB2
厂商: Silicon Laboratories Inc
文件页数: 25/34页
文件大小: 783K
描述: KIT DEV TEST EZRADIO SI4021 TX
标准包装: 1
附件类型: 测试卡,发射器,915MHz
适用于相关产品: EZRadio?
Si4021
 
 
25
RESET MODES 
The chip will enter into reset mode if any of the following conditions are met:
?    Power-on reset: During a power up sequence until the Vdd has reached the correct level and stabilized
?    Power glitch reset: Transients present on the V
dd
 line
?    Software reset: Special control command received by the chip
Power-on reset
After power up the supply voltage starts to rise from 0V. The reset block has an internal ramping voltage reference (reset-ramp signal), which
is rising at 100mV/ms (typical) rate. The chip remains in reset state while the voltage difference between the actual Vdd and the internal
reset-ramp signal is higher than the reset threshold voltage, which is 600 mV (typical). As long as the Vdd voltage is less than 1.6V (typical)
the chip stays in reset mode regardless the voltage difference between the Vdd and the internal ramp signal.
The reset event can last up to 150ms supposing that the V
dd
 reaches 90% its final value within 1ms. During this period the chip does not
accept control commands via the serial control interface.
Power-on reset example:
 
Power glitch reset
The internal reset block has two basic mode of operation: normal and sensitive reset. The default mode is sensitive, which can be changed
by the appropriate control command (see Related control commands at the end of this section). In normal mode the power glitch detection
circuit is disabled.
There can be spikes or glitches on the V
dd
 line if the supply filtering is not satisfactory or the internal resistance of the power supply is too
high. In such cases if the sensitive reset is enabled an (unwanted) reset will be generated if the positive going edge of the V
dd
 has a rising
rate greater than 100mV/ms and the voltage difference between the internal ramp signal and the V
dd
 reaches the reset threshold voltage
(600 mV). Typical case when the battery is weak and due to its increased internal resistance a sudden decrease of the current consumption
(for example turning off the power amplifier) might lead to an increase in supply voltage. If for some reason the sensitive reset cannot be
disabled step-by-step decrease of the current consumption (by turning off the different stages one by one) can help to avoid this problem.
Any negative change in the supply voltage will not cause reset event unless the Vdd level reaches the reset threshold voltage (250mV in
normal mode, 1.6V in sensitive reset mode).
If the sensitive mode is disabled and the power supply turned off the Vdd must drop below 250mV in order to trigger a power-on reset event
when the supply voltage is turned back on. If the decoupling capacitors keep their charges for a long time it could happen that no reset will
be generated upon power-up because the power glitch detector circuit is disabled.
Note that the reset event reinitializes the internal registers, so the sensitive mode will be enabled again.
相关PDF资料
PDF描述
4022-DKDB13 KIT DEV TEST EZRADIO SI4022 TX
4320-DKDB5 KIT DEV TEST EZRADIO SI4320 RX
4320-DKDB4 KIT DEV TEST EZRADIO SI4320 RX
PSL0101WBFD1 LED WHITE 90LM 350MA 3000K SSML
PSL0101WBFB1 LED WHITE 80LM 350MA 3000K SSML
相关代理商/技术参数
参数描述
4021-DKDB3 功能描述:射频开发工具 Test Board BIFA Tx (868MHz) RoHS:否 制造商:Taiyo Yuden 产品:Wireless Modules 类型:Wireless Audio 工具用于评估:WYSAAVDX7 频率: 工作电源电压:3.4 V to 5.5 V
4021-DKDB7 功能描述:射频开发工具 Test Board xloop Tx (915/868MHz) RoHS:否 制造商:Taiyo Yuden 产品:Wireless Modules 类型:Wireless Audio 工具用于评估:WYSAAVDX7 频率: 工作电源电压:3.4 V to 5.5 V
4021-G 功能描述:4021 ELARA MOON MODULE GREEN RoHS:是 类别:光电元件 >> LED - 高亮度电源模块 系列:4021 ELRA MOON 标准包装:36 系列:5027 TFFC STAR K2 颜色:暖白色 配置:星形 在特定电流下的光通量 - 测试:75lm 电流 - 测试:350mA 电流 - 最大:1.5A 带连接器:无 驱动器电路:无 波长:- 电压:-
4021M 制造商:3M Electronic Products Division 功能描述:4021-M MS2 SPLICING RIG W/4031 80610026207 制造商:3M Electronic Products Division 功能描述:MS2 SPLICING RIG W/4031 HAND PUMP
4021-M/36 功能描述:工具套件与外壳 MS2 SPLICING RIG W/4036-25 HND CRIMPR RoHS:否 制造商:Molex 产品: 类型: 大小: