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24MHz Crystal for RT1064 custom board

Question asked by Lars Wallden on Jan 30, 2020
Latest reply on Feb 5, 2020 by Lars Wallden

Hello, I have a custom board design for the MIMXRT1064DVL6A with a 24 MHz crystal connected as recommended in the documentation. I have read an earlier thread about a similar problem where the result was that the crystal was faulty. Since that is an old thread I start a new with a similar problem but for the RT1064. I suppose the whole family uses a similar crystal oscillator circuit.

 

I have referenced the MIMXRT105060HDUG Hardware development guide. The IMXRT1064IEC Technical data sheet and the IMX25CEC Technical datasheet. From this documentation, I understand that a crystal with the following data can be used: "A typical 80 ESR crystal rated for a maximum drive level of 250 μW is acceptable", it also says: 24.0 MHz crystal should be connected between XTALI and XTALO. That is quite clear instructions with a wide choice of crystals available.

I have put a 2.2M Ohm resistor between GND and P11 (Xtal 1) for the startup of the oscillator as recommended.

 

The crystal I have chosen is the XRCGB24M000F1H00R0  XRCGB24M000F1H00R0|Ceramic Resonators/Crystal Units/MEMS Resonators|Timing Devices|Murata Manufacturing Co., Ltd. 

With the following data:

Specifications
Product Type Crystal Unit
Series XRCGB
Type HCR2016
Frequency 24.0000MHz
Frequency Tolerance +/-10ppm max. (25+/-3℃)
Operating Temperature Range -20℃ to 70℃
Frequency Shift by Temperature +/-10ppm max.
Frequency Aging +/-2ppm max./year
Equivalent Series Resistance (ESR) 80ohm max.
Drive Level (DL) 150μW (300μW max.)
Load Capacitance (Cs) 6pF
Shape SMD
Wash Not available
L x W (size) 2.0x1.6mm

 

 

The oscillator does not start. Can you see any problems with this crystal choice for the RT1064?

 

I look forward to your answer.

 

Thanks.

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