CC2640低功耗时，32.768K晶振无法起振

xing wang8

Other Parts Discussed in Thread: CC2640, CC2640R2F, CC2650

我手头上两块板子，一个是7*7的开发板，一个是4*4的自己调试的板子。为了排除软件问题，我重装了了IT的协议栈，默认使用的例程是SimpleBLEPeripheral，IAR设置为POWER_SAVING模式，7*7的正常，但是设置为4XS烧录到4*4的板子32K的晶振就无法起振，

如果设置为xPOWER_SAVING模式，4*4的又可以起振了，请问该种原因是什么导致的？硬件重新焊接了好几遍，晶振也换了。

7 年多前

0 Terry Han 7 年多前

TI__Genius 13140 points

注意在不使用使32k晶体的时，必须是CC2640量产版本为PG2.3，版本信息可以通过Flash Programmer 2进行芯片连接后查看

参考：Running Bluetooth® low energy on CC2640 Without 32k

CC2640 Hardware Revision In order to use the 32kHz crystal less feature, a CC2640R2F or CC2640/CC2650 device with silicon revision PG2.3 or later is required. For more details, see the CC2640 SimpleLink™ Wireless MCU Errata. There are three ways to determine the chip revision: • Use ChipInfo_GetMinorHwRev(), which can be found in chipinfo.h in our driverlib. This function returns 0 for the older revision and 1 or higher for later revisions (PG2.3 or newer). Only the latter supports usage of the 32 kHz RC oscillator. • For CC2640/CC2650, you can check the revision label on the box the chips comes shipped in. The revision should be “D” or higher. • Use Flash Programmer 2. You can find the revision number at the lower left corner as shown below

The 32-kHz crystal is optional. Bluetooth low energy requires a slow-speed clock with better than ±500 ppm accuracy if the device is to enter any sleep mode while maintaining a connection. The internal 32-kHz RC oscillator can in some use cases be compensated to meet the requirements. The low-speed crystal oscillator is designed for use with a 32-kHz watch-type crystal.