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SM470低功耗问题

请问SM470在standby模式下如何关闭PLL?

Susan Yang:

您的芯片是否有PLLDIS这个pin?

Donglai Zhou:

回复 Susan Yang:

有的,已经按手册建议,下拉接GND

Susan Yang:

回复 Donglai Zhou:

现在可以正常disable了?

Donglai Zhou:

回复 Susan Yang:

初步判断standby模式下无法disable,下拉接GND应该没有影响吧?是否按指南进行程序配置就可以?

Susan Yang:

回复 Donglai Zhou:

您可以在的数据手册内看到说明

The enhanced RTI module is the system module with two extra bits to disable the ZPLL while in STANDBY mode.

以及

www.ti.com/…/spnu212b.pdf

The PLLDIS pin enables bypassing the PLL for emulation and testing. This pin is essential for speeding up test time, which reduces chip cost. It cannot be multiplexed with another pin or general purpose input-output (GPIO) due to the various pin permutations required during test. The device can be used in bypass mode with only the crystal oscillator (PLL disabled);

Donglai Zhou:

回复 Susan Yang:

已按照手册上说明对RTI进行配置,未起作用

参考说明为:
Once RTI OSC EN is programmed, the source of RTICLK is the oscillator for
all operating modes. When PLL STBY DIS is programmed, the PLL is
disabled upon entering STBY mode. This results in lower current
consumption. When the device is awakened from STBY mode, the PLL will
relock. An external interrupt to the CIM/IEM will trigger the PLL to start the
relock process. While the PLL relocks, the system clocks are held off for 4096
cycles. See Table 7 for the clocks available to the RTI module and the
corresponding PLL activities during standby mode.

Susan Yang:

回复 Donglai Zhou:

理论上这样就可以了,而且您下拉接GND了。

您是如何查看PLL没有禁用的呢?另外建议您看一下下面的帖子,客户已经实现了standby下低功耗

e2e.ti.com/…/452344

Donglai Zhou:

回复 Susan Yang:

单片机进入standby模式后,IO电流监测为27mA,核心电流为23mA,以此为判断依据。我会看一下您发的链接并分析。

Donglai Zhou:

回复 Susan Yang:

单片机进入standby模式后,IO电流监测为27mA,核心电流为23mA,以此为判断依据。我会看一下您发的链接并分析。

Donglai Zhou:

回复 Donglai Zhou:

因为需要用到倍频分频,PLLDIS下拉,PLL没有进入BYPASS模式,是否这个有影响?

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