| 数据搜索系统,热门电子元器件搜索 |
|
LAN9252/ML 数据表(PDF) 206 Page - Microchip Technology |
|
|
|||||||||||||||||||||||||||||
LAN9252/ML 数据表(HTML) 206 Page - Microchip Technology |
|
206 / 329 page ![]() LAN9252 DS00001909A-page 206 2015 Microchip Technology Inc. 12.9.7 EXTERNAL PHY TIMING Since the EtherCAT Core does not use the PHY transmit clock, proper timing must be ensured based on the common 25 MHz reference clock (which is output to the external PHY via the MII_CLK25 pin). To aid in this, the EtherCAT Core has the TX shift feature enabled. This feature can delay the generation of the transmit signals from the EtherCAT Core by 0ns, 10ns, 20ns or 30ns. This value is manually set using tx_shift_strap[1:0]. 12.9.7.1 MII Connection Timing The MII interface TX and RX timing is as follows: Note 1: Timing is designed for a system load between 10 pF and 25 pF. Note 2: Assumes TX shift value of 2, add 10 ns for each increment of TX shift (shift values of 3, 0, and 1 in order). FIGURE 12-7: MII TX TIMING TABLE 12-4: MII TX TIMING VALUES Symbol Description Min Max Units Notes tclkp MII_CLK25 period 40 - ns tclkh MII_CLK25 high time tclkp * 0.45 tclkp * 0.55 ns tclkl MII_CLK25 low time tclkp * 0.45 tclkp * 0.55 ns tval MII_TXD[3:0], MII_TXEN output valid from rising edge of MII_CLK25 Note 2 - 10.0 ns Note 1 thold MII_TXD[3:0], MII_TXEN output hold from rising edge of MII_CLK25 Note 2 0- ns Note 1 MII_CLK25 MII_TXD[3:0] MII_TXEN tclkh tclkl tclkp tval thold (output) tval tval thold |
|
链接网址 |
| ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 数据表链接 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |