[参考译文] DS90UB960-Q1：REFCLK 寄存器值与示波器测得的频率不同

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1195527/ds90ub960-q1-refclk-register-value-is-different-from-the-measured-frequency-by-oscilloscope

您好！

我们的团队正在开发使用两个 DS90UB960的电路板。   我们遇到不稳定和锁定失败的问题、因此我们连接了 USB2ANY 并通过 ALP 监控状态。
我们已经注意到、尽管我们肯定会使用25MHz 时钟对 REFCLK 进行馈送、但解串器会将 REFCLK 测量为28Mhz。  原因可能是什么？

这是我们要馈送的25MHz 时钟：


我们试图通过  为解串器提供22Mhz 时钟来"欺骗"解串器、但实际上它正常工作。 报告的 REFCLK 变为25MHz 并且 Lock\Pass 稳定而没有错误。 (底部图片)
此外、随附的寄存器转储来自串行器/解串器、同时使用22Mhz 馈送解串器。



953_REGISTER.NRD：

[REGISTERS]
Device = ALP Nano 1 - DS90UB953, Connector 1
Comments = "953_registers"
Date = 02/12/2023
Time = 22:24:34
Reg = 0,0x0000,0x30
Reg = 0,0x0001,0x00
Reg = 0,0x0002,0x33
Reg = 0,0x0003,0x48
Reg = 0,0x0004,0x00
Reg = 0,0x0005,0x03
Reg = 0,0x0006,0x41
Reg = 0,0x0007,0x28
Reg = 0,0x0008,0xFE
Reg = 0,0x0009,0x1E
Reg = 0,0x000A,0x10
Reg = 0,0x000B,0x7F
Reg = 0,0x000C,0x7F
Reg = 0,0x000D,0xF0
Reg = 0,0x000E,0x0F
Reg = 0,0x0010,0x00
Reg = 0,0x0011,0x00
Reg = 0,0x0013,0x00
Reg = 0,0x0014,0x00
Reg = 0,0x0015,0x20
Reg = 0,0x0017,0x3C
Reg = 0,0x0018,0x80
Reg = 0,0x0019,0x62
Reg = 0,0x001A,0x62
Reg = 0,0x001B,0x62
Reg = 0,0x001C,0x00
Reg = 0,0x001D,0x00
Reg = 0,0x001E,0x00
Reg = 0,0x0020,0x00
Reg = 0,0x0021,0x00
Reg = 0,0x0022,0x00
Reg = 0,0x0023,0x00
Reg = 0,0x0024,0x00
Reg = 0,0x0031,0x20
Reg = 0,0x0032,0x09
Reg = 0,0x0033,0x04
Reg = 0,0x0035,0x11
Reg = 0,0x0037,0x7A
Reg = 0,0x0039,0x00
Reg = 0,0x003A,0x00
Reg = 0,0x003B,0x00
Reg = 0,0x003C,0x00
Reg = 0,0x003D,0x00
Reg = 0,0x003E,0x00
Reg = 0,0x003F,0x00
Reg = 0,0x0040,0x00
Reg = 0,0x0041,0x00
Reg = 0,0x0042,0x00
Reg = 0,0x0043,0x00
Reg = 0,0x0044,0x00
Reg = 0,0x0045,0x00
Reg = 0,0x0046,0x00
Reg = 0,0x0047,0x00
Reg = 0,0x0048,0x00
Reg = 0,0x0049,0x00
Reg = 0,0x0050,0x20
Reg = 0,0x0051,0xC0
Reg = 0,0x0052,0x45
Reg = 0,0x0053,0x06
Reg = 0,0x0054,0x00
Reg = 0,0x0055,0x00
Reg = 0,0x0056,0x00
Reg = 0,0x0057,0x00
Reg = 0,0x0058,0x07
Reg = 0,0x0059,0x07
Reg = 0,0x005A,0x07
Reg = 0,0x005C,0x00
Reg = 0,0x005D,0x00
Reg = 0,0x005E,0x00
Reg = 0,0x005F,0x00
Reg = 0,0x0060,0x00
Reg = 0,0x0061,0x00
Reg = 0,0x0062,0x00
Reg = 0,0x0063,0x00
Reg = 0,0x0064,0x00
Reg = 0,0x00B0,0x04
Reg = 0,0x00B1,0x4A
Reg = 0,0x00B2,0x3F
Reg = 0,0x00F0,0x5F
Reg = 0,0x00F1,0x55
Reg = 0,0x00F2,0x42
Reg = 0,0x00F3,0x39
Reg = 0,0x00F4,0x35
Reg = 0,0x00F5,0x33

[REGISTERS]
Device = ALP Nano 1 - DS90UB960, Connector 1
Comments = "960"
Date = 02/12/2023
Time = 22:24:10
Reg = 0,0x0000,0x7A
Reg = 0,0x0001,0x00
Reg = 0,0x0002,0x1E
Reg = 0,0x0003,0x40
Reg = 0,0x0004,0xD0
Reg = 0,0x0005,0x01
Reg = 0,0x0006,0x00
Reg = 0,0x0007,0xFE
Reg = 0,0x0008,0x1C
Reg = 0,0x0009,0x10
Reg = 0,0x000A,0x7A
Reg = 0,0x000B,0x7A
Reg = 0,0x000C,0x0F
Reg = 0,0x000D,0x09
Reg = 0,0x000E,0x00
Reg = 0,0x000F,0xFF
Reg = 0,0x0010,0x00
Reg = 0,0x0011,0x00
Reg = 0,0x0012,0x00
Reg = 0,0x0013,0x00
Reg = 0,0x0014,0x00
Reg = 0,0x0015,0x00
Reg = 0,0x0016,0x00
Reg = 0,0x0017,0x00
Reg = 0,0x0018,0x00
Reg = 0,0x0019,0x00
Reg = 0,0x001A,0x00
Reg = 0,0x001B,0x00
Reg = 0,0x001C,0x00
Reg = 0,0x001D,0x00
Reg = 0,0x001E,0x04
Reg = 0,0x001F,0x02
Reg = 0,0x0020,0xF0
Reg = 0,0x0021,0x03
Reg = 0,0x0022,0x00
Reg = 0,0x0023,0x00
Reg = 0,0x0024,0x00
Reg = 0,0x0025,0x00
Reg = 0,0x0026,0x00
Reg = 0,0x0027,0x00
Reg = 0,0x0028,0x00
Reg = 0,0x0029,0x00
Reg = 0,0x002A,0x00
Reg = 0,0x002B,0x00
Reg = 0,0x002C,0x00
Reg = 0,0x002D,0x00
Reg = 0,0x002E,0x00
Reg = 0,0x002F,0x00
Reg = 0,0x0030,0x00
Reg = 0,0x0031,0x00
Reg = 0,0x0032,0x00
Reg = 0,0x0033,0x00
Reg = 0,0x0034,0x00
Reg = 0,0x0035,0x00
Reg = 0,0x0036,0x00
Reg = 0,0x0037,0x00
Reg = 0,0x0038,0x00
Reg = 0,0x0039,0x00
Reg = 0,0x003A,0x00
Reg = 0,0x0040,0x00
Reg = 0,0x0041,0xA9
Reg = 0,0x0042,0x71
Reg = 0,0x0043,0x01
Reg = 0,0x0044,0x00
Reg = 0,0x0045,0x00
Reg = 0,0x0046,0x20
Reg = 0,0x0047,0x00
Reg = 0,0x004C,0x00
Reg = 0,0x004D,0x03
Reg = 0,0x004E,0x0C
Reg = 0,0x004F,0x64
Reg = 0,0x0050,0x00
Reg = 0,0x0051,0x00
Reg = 0,0x0052,0x00
Reg = 0,0x0053,0x03
Reg = 0,0x0054,0x00
Reg = 0,0x0055,0x00
Reg = 0,0x0056,0xA1
Reg = 0,0x0057,0x00
Reg = 0,0x0058,0x5E
Reg = 0,0x0059,0x00
Reg = 0,0x005A,0x00
Reg = 0,0x005B,0x30
Reg = 0,0x005C,0x18
Reg = 0,0x005D,0x00
Reg = 0,0x005E,0x00
Reg = 0,0x005F,0x00
Reg = 0,0x0060,0x00
Reg = 0,0x0061,0x00
Reg = 0,0x0062,0x00
Reg = 0,0x0063,0x00
Reg = 0,0x0064,0x00
Reg = 0,0x0065,0x00
Reg = 0,0x0066,0x00
Reg = 0,0x0067,0x00
Reg = 0,0x0068,0x00
Reg = 0,0x0069,0x00
Reg = 0,0x006A,0x00
Reg = 0,0x006B,0x00
Reg = 0,0x006C,0x00
Reg = 0,0x006D,0x7C
Reg = 0,0x006E,0x88
Reg = 0,0x006F,0x88
Reg = 0,0x0070,0x2B
Reg = 0,0x0071,0x2C
Reg = 0,0x0072,0xE4
Reg = 0,0x0073,0x00
Reg = 0,0x0074,0x00
Reg = 0,0x0075,0x00
Reg = 0,0x0076,0x00
Reg = 0,0x0077,0xC5
Reg = 0,0x0078,0x00
Reg = 0,0x0079,0x01
Reg = 0,0x007A,0x0F
Reg = 0,0x007B,0xFF
Reg = 0,0x007C,0x20
Reg = 0,0x007D,0x00
Reg = 0,0x007E,0x00
Reg = 0,0x007F,0x00
Reg = 0,0x0090,0x00
Reg = 0,0x0091,0x00
Reg = 0,0x0092,0x00
Reg = 0,0x0093,0x00
Reg = 0,0x0094,0x00
Reg = 0,0x0095,0x00
Reg = 0,0x0096,0x00
Reg = 0,0x0097,0x00
Reg = 0,0x0098,0x00
Reg = 0,0x0099,0x00
Reg = 0,0x009A,0x00
Reg = 0,0x009B,0x00
Reg = 0,0x009C,0x00
Reg = 0,0x009D,0x00
Reg = 0,0x009E,0x00
Reg = 0,0x009F,0x00
Reg = 0,0x00A5,0x19
Reg = 0,0x00B0,0x1C
Reg = 0,0x00B1,0x3A
Reg = 0,0x00B2,0x14
Reg = 0,0x00B3,0x08
Reg = 0,0x00B8,0xFC
Reg = 0,0x00B9,0x33
Reg = 0,0x00BA,0x83
Reg = 0,0x00BB,0x74
Reg = 0,0x00BC,0x80
Reg = 0,0x00BD,0x00
Reg = 0,0x00BE,0x00
Reg = 0,0x00D0,0x00
Reg = 0,0x00D1,0x43
Reg = 0,0x00D2,0x94
Reg = 0,0x00D3,0x0F
Reg = 0,0x00D4,0x60
Reg = 0,0x00D5,0xF2
Reg = 0,0x00D6,0x00
Reg = 0,0x00D7,0x03
Reg = 0,0x00D8,0x00
Reg = 0,0x00D9,0x00
Reg = 0,0x00DA,0x00
Reg = 0,0x00DB,0x00
Reg = 0,0x00DC,0x00
Reg = 0,0x00DD,0x00
Reg = 0,0x00DE,0x00
Reg = 0,0x00DF,0x00
Reg = 0,0x00F0,0x5F
Reg = 0,0x00F1,0x55
Reg = 0,0x00F2,0x42
Reg = 0,0x00F3,0x39
Reg = 0,0x00F4,0x36
Reg = 0,0x00F5,0x30
Reg = 0,0x00F8,0x00
Reg = 0,0x00F9,0x00
Reg = 0,0x00FA,0x00
Reg = 0,0x00FB,0x00

这是原理图(第4页有2个解串器)：

e2e.ti.com/.../main_5F00_pcb.pdf

布局文件：

e2e.ti.com/.../MCS_5F00_main_5F00_041222_5F00_051222.zip

e2e.ti.com/.../main_5F00_pcb_5F005F00_Layout_5F00_pdf.zip

编辑：

我在这里找到了简单的线程、但没有一个线程给出了解决方案/根本原因的解释。 我们测量了 VCCIO (1.8)和3.3/2.5。  所有电压都是稳定的。

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/904763/ds90ub960-q1evm-ds90ub960-q1evm-refclk-pin-input-is-25mhz-but-i2c-register-0xa5-of-90960-is-0x1c-28mhz

e2e.ti.com/.../3738416