DP83822HF: DP83822 OSC level requirement

Kelvin Lo

Part Number: DP83822HF
Other Parts Discussed in Thread: DP83822EVM, DP83822I

Referring to the DP83822 specification, the requirement of the XI pin can be used CMOS -level oscillator. What is the CMOS -level oscillator? What is the level requirement of the oscillator? Vpp level? any the rise time and fall time requirement? Because of some units did not work( pin17 LED turn off ) during the production.

Attached, please find the OSC waveform for your reference.

over 5 years ago

0 Kelvin Lo over 5 years ago

Prodigy 250 points

Hi TI Support team,

Any update about the above issue. If the OSC Vpp over 3.7V go into the XI pin. Will the X1 pin damage? Any register value can check the OSC clock is normal or not? Please advise with thanks!

Regards

Kelvin

0 Cecilia Reyes over 5 years ago in reply to Kelvin Lo

TI__Genius 9920 points

Hi Kelvin,

Apologies on the late response as we do not check our E2Es outside of office hours and weekends. The CMOS oscillator is another option for an external clock on the XI pin. As for information on CMOS levels, please check out our User's Guide on the DP83822EVM for more information on the specs and requirements.

https://www.ti.com/lit/ug/snlu179/snlu179.pdf

Have you considered using a crystal instead? Here is our application note on timing requirements and crystal specs as well: https://www.ti.com/lit/an/snla290/snla290.pdf

0 Kelvin Lo over 5 years ago in reply to Cecilia Reyes

Prodigy 250 points

Hi Support team,

In the document that you provided that it is not mentioned about the Xin minimum voltage level and maximum voltage level. And also the requirement of the oscillator. We already using the external oscillator for the system clock. However, the solved the EMI issue, we lower the OSC level down to 2.0Vpp as below mentioned. We will afraid the system is not stable. Please advise with thanks.

0 Wiky Liao over 5 years ago in reply to Cecilia Reyes

TI__Intellectual 1830 points

Hi Cecilia,

I want to follow Kelvin's questions here and share more info.

Currently we find the crystal Vpp amplitude will influence the DP83822I working. If the crystal amplitude is 2.6V(Kevlin have attached the waveform), DP83822I can't get the IP address, so it doesn't work in system. But if we change the crystal amplitude to 2.92V, DP83822I works normally. So we want to know what's the amplitude requirement of crystal, such as minimum Vpp or maximum Vpp, raising time/falling time or others.

We also dump the register when issue occurs(Vpp=2.6V), and normal work register(Vpp=2.92V), hope it can help you to check the issue.

Issue occurs:

> do echo -en "$reg: " && phytool write em1/9/0xd 0x1f && phytool write em1/9/0xe $reg && phytool write em1/9/0xd 0x401f && phytool read em1/9/0xe; done
0x0000: 0x3100
0x0001: 0x7849
0x0002: 0x2000
0x0003: 0xa240
0x0004: 0x01e1
0x0005: 0000
0x0006: 0x0005
0x0007: 0x2001
0x0008: 0000
0x0009: 0000
0x000A: 0x0100
0x000B: 0x1000
0x000C: 0000
0x000D: 0x401f
0x000E: 0000
0x000F: 0000
0x0010: 0x0002
0x0011: 0x0108
0x0012: 0000
0x0013: 0x0800
0x0014: 0x0014
0x0015: 0000
0x0016: 0x0100
0x0017: 0x00e1
0x0018: 0x0400
0x0019: 0x8009
0x001A: 0000
0x001B: 0x007d
0x001C: 0x05ee
0x001D: 0000
0x001E: 0x0102
0x001F: 0000
0x0025: 0x0040
0x0027: 0000
0x003E: 0000
0x003F: 0xb4ff
0x0042: 0x0042
0x0106: 0xb0bb
0x0107: 0x0605
0x010F: 0x0300
0x0114: 0x400a
0x0116: 0x0006
0x0126: 0x461b
0x0155: 0x0001
0x0170: 0x0e52
0x0171: 0xc85c
0x0173: 0xff1e
0x0177: 0x189b
0x0180: 0000
0x0181: 0000
0x0182: 0000
0x0183: 0000
0x0184: 0000
0x0185: 0000
0x0186: 0000
0x0187: 0000
0x0188: 0000
0x0189: 0000
0x018A: 0000
0x0215: 0x01af
0x021D: 0x0600
0x0403: 0x9fcf
0x0404: 0x0024
0x0428: 0000
0x0456: 0x0008
0x0460: 0x0551
0x0461: 0x0410
0x0462: 0x0001
0x0463: 0000
0x0465: 0xff00
0x0467: 0x0f7f
0x0468: 0x0003
0x0469: 0x0040
0x04A0: 0x1000
0x04A1: 0000
0x04A2: 0000
0x04A3: 0000
0x04A4: 0000
0x04A5: 0000
0x04A6: 0000
0x04A7: 0000
0x04A8: 0000
0x04A9: 0000
0x04AA: 0000
0x04AB: 0000
0x04AC: 0000
0x04AD: 0000
0x04AE: 0000
0x04AF: 0000
0x04B0: 0000
0x04B1: 0000
0x04B2: 0000
0x04B3: 0000
0x04B4: 0000
0x04B5: 0000
0x04B6: 0000
0x04B7: 0000
0x04B8: 0000
0x04B9: 0000
0x04BA: 0000
0x04BB: 0000
0x04BC: 0000
0x04BD: 0000
0x04BE: 0000
0x04BF: 0000
0x04C0: 0000
0x04C1: 0000
0x04C2: 0000
0x04C3: 0000
0x04C4: 0000
0x04C5: 0000
0x04C6: 0000
0x04C7: 0000
0x04C8: 0000
0x04C9: 0000
0x04CA: 0000
0x04CB: 0000
0x04CC: 0x000c
0x04D0: 0x0302
0x04D1: 0x018b
0x04D4: 0x7220
0x04D5: 0xfbc1
0x04D6: 0x01c1
0x3000: 0x3100
0x3001: 0x7849
0x3014: 0000
0x3016: 0x0100
0x703C: 0000
0x703D: 0000

normal working(no cable plugged in):

0x0000: 0x3100
0x0001: 0x786d
0x0002: 0x2000
0x0003: 0xa240
0x0004: 0x01e1
0x0005: 0x45e1
0x0006: 0x0005
0x0007: 0x2001
0x0008: 0000
0x0009: 0000
0x000A: 0x0100
0x000B: 0x1000
0x000C: 0000
0x000D: 0x401f
0x000E: 0000
0x000F: 0000
0x0010: 0x4e15
0x0011: 0x0108
0x0012: 0000
0x0013: 0000
0x0014: 0x0014
0x0015: 0000
0x0016: 0x0100
0x0017: 0x00e5
0x0018: 0x0400
0x0019: 0x8c09
0x001A: 0000
0x001B: 0x007d
0x001C: 0x05ee
0x001D: 0000
0x001E: 0x0102
0x001F: 0000
0x0025: 0x0040
0x0027: 0000
0x003E: 0000
0x003F: 0x0042
0x0042: 0000
0x0106: 0xb0bb
0x0107: 0x0605
0x010F: 0x0300
0x0114: 0x0006
0x0116: 0x0126
0x0126: 0x461b
0x0155: 0x1f31
0x0170: 0x0e52
0x0171: 0xc85c
0x0173: 0xff1e
0x0177: 0x189b
0x0180: 0000
0x0181: 0000
0x0182: 0000
0x0183: 0000
0x0184: 0000
0x0185: 0000
0x0186: 0000
0x0187: 0000
0x0188: 0000
0x0189: 0000
0x018A: 0000
0x0215: 0x0780
0x021D: 0x0434
0x0403: 0x9fcf
0x0404: 0x0024
0x0428: 0000
0x0456: 0x0008
0x0460: 0x0551
0x0461: 0x0410
0x0462: 0x0001
0x0463: 0000
0x0465: 0xff00
0x0467: 0x0f7f
0x0468: 0x0003
0x0469: 0x0040
0x04A0: 0x1000
0x04A1: 0000
0x04A2: 0000
0x04A3: 0000
0x04A4: 0000
0x04A5: 0000
0x04A6: 0000
0x04A7: 0000
0x04A8: 0000
0x04A9: 0000
0x04AA: 0000
0x04AB: 0000
0x04AC: 0000
0x04AD: 0000
0x04AE: 0000
0x04AF: 0000
0x04B0: 0000
0x04B1: 0000
0x04B2: 0000
0x04B3: 0000
0x04B4: 0000
0x04B5: 0000
0x04B6: 0000
0x04B7: 0000
0x04B8: 0000
0x04B9: 0000
0x04BA: 0000
0x04BB: 0000
0x04BC: 0000
0x04BD: 0000
0x04BE: 0000
0x04BF: 0000
0x04C0: 0000
0x04C1: 0000
0x04C2: 0000
0x04C3: 0000
0x04C4: 0000
0x04C5: 0000
0x04C6: 0000
0x04C7: 0000
0x04C8: 0000
0x04C9: 0000
0x04CA: 0000
0x04CB: 0000
0x04CC: 0x000f
0x04D0: 0x0302
0x04D1: 0x018b
0x04D4: 0x7220
0x04D5: 0xfbc1
0x04D6: 0x01c1
0x3000: 0x3100
0x3001: 0x786d
0x3014: 0000
0x3016: 0x0100
0x703C: 0000
0x703D: 0000

Normal working(cable is plugged in):

0x0000: 0x3100
0x0001: 0x786d
0x0002: 0x2000
0x0003: 0xa240
0x0004: 0x01e1
0x0005: 0x45e1
0x0006: 0x0005
0x0007: 0x2001
0x0008: 0000
0x0009: 0000
0x000A: 0x0100
0x000B: 0x1000
0x000C: 0000
0x000D: 0x401f
0x000E: 0000
0x000F: 0000
0x0010: 0x4e15
0x0011: 0x0108
0x0012: 0000
0x0013: 0000
0x0014: 0x0014
0x0015: 0000
0x0016: 0x0100
0x0017: 0x00e5
0x0018: 0x0400
0x0019: 0x8c09
0x001A: 0000
0x001B: 0x007d
0x001C: 0x05ee
0x001D: 0000
0x001E: 0x0102
0x001F: 0000
0x0025: 0x0040
0x0027: 0000
0x003E: 0000
0x003F: 0x0042
0x0042: 0000
0x0106: 0xb0bb
0x0107: 0x0605
0x010F: 0x0300
0x0114: 0x0006
0x0116: 0x0126
0x0126: 0x461b
0x0155: 0x1f31
0x0170: 0x0e52
0x0171: 0xc85c
0x0173: 0xff1e
0x0177: 0x189b
0x0180: 0000
0x0181: 0000
0x0182: 0000
0x0183: 0000
0x0184: 0000
0x0185: 0000
0x0186: 0000
0x0187: 0000
0x0188: 0000
0x0189: 0000
0x018A: 0000
0x0215: 0x0780
0x021D: 0x042a
0x0403: 0x9fcf
0x0404: 0x0024
0x0428: 0000
0x0456: 0x0008
0x0460: 0x0551
0x0461: 0x0410
0x0462: 0x0001
0x0463: 0000
0x0465: 0xff00
0x0467: 0x0f7f
0x0468: 0x0003
0x0469: 0x0040
0x04A0: 0x1000
0x04A1: 0000
0x04A2: 0000
0x04A3: 0000
0x04A4: 0000
0x04A5: 0000
0x04A6: 0000
0x04A7: 0000
0x04A8: 0000
0x04A9: 0000
0x04AA: 0000
0x04AB: 0000
0x04AC: 0000
0x04AD: 0000
0x04AE: 0000
0x04AF: 0000
0x04B0: 0000
0x04B1: 0000
0x04B2: 0000
0x04B3: 0000
0x04B4: 0000
0x04B5: 0000
0x04B6: 0000
0x04B7: 0000
0x04B8: 0000
0x04B9: 0000
0x04BA: 0000
0x04BB: 0000
0x04BC: 0000
0x04BD: 0000
0x04BE: 0000
0x04BF: 0000
0x04C0: 0000
0x04C1: 0000
0x04C2: 0000
0x04C3: 0000
0x04C4: 0000
0x04C5: 0000
0x04C6: 0000
0x04C7: 0000
0x04C8: 0000
0x04C9: 0000
0x04CA: 0000
0x04CB: 0000
0x04CC: 0x000f
0x04D0: 0x0302
0x04D1: 0x018b
0x04D4: 0x7220
0x04D5: 0xfbc1
0x04D6: 0x01c1
0x3000: 0x3100
0x3001: 0x786d
0x3014: 0000
0x3016: 0x0100
0x703C: 0000
0x703D: 0000

Best Regards.

Wiky

0 Kelvin Lo over 5 years ago in reply to Wiky Liao

Prodigy 250 points

HI TI support team,

Refer to the 83822 specifications

The VoH is 1.7V, and VoL is 0.8V, is it mean the oscillator voltage over 1.7V is high level and oscillator voltage less than 0.8V is defined as low level?

And How to define the rise and fall time? by using the high reference voltage level is1.7V and low reference voltage level is 0.8V or high reference level is 90% of VDDIO = 2.97V and low reference level is 10% of VDDIO =0.33V. Please advise with thanks!

Regards

Kelvin

0 Cecilia Reyes over 5 years ago in reply to Kelvin Lo

TI__Genius 9920 points

Hi Kelvin and Wiky,

Let's close this thread as we have directed this conversation to emails.

Thank you.

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DP83822HF: DP83822 OSC level requirement