1.Setting
a.Hardware circuit
0.1 uF
IP101G
冯理达
Tx + or Rx+ or黄道吉日的意思
Original PHY-to-PHY Circuit
Tx - or
At the left side, point C and point E of IP101G should not be connected to neither any resistor nor any power source.
At the right side, there are 2 possibilities for the power source of point B—No connection or VDD_B, depending on the vendor’s design. If other vendor’s PHY requires a supply voltage on the central tap of the transformer, then VDD_B should be applied to Point B; otherwi Point B does not need a power source.
Note. The AC Bypass Capacitor should be added.
2.DC Spec in RX of IP101G PHY to PHY
DC typical: 1.65V
Peak to Peak: minimum = +- 0.45V, maximum = +- 0.65V
3. Simplified PHY to PHY circuit
No matter what the design architecture is, Point B are at the stable DC voltage. From the viewpoint of the AC coupled signal, all stable DC voltage points can be treated as short circuit. The simplified circuit from the Tx side of IP101G to Rx side of other vendor’s PHY can be reprented by the following figure.
12 mA
Simplified PHY-to-PHY Circuit
4. Amplitude Calculation Model
Becau our concern is the AC coupled signal, we can make the capacitor short and ignore the loading effect of Rx differential load. The final simplified circuit can be reprented by
12 mA Amplitude Calculation Model
0V -Vp
The max differential voltage crossing R2 is 300mV. In the other word, +Vp and –Vp are 300mV and –300mV respectively. The real measured value will be less than this, becau we bypass the loss of
魏国武将排名capacitor in the calculation.
Becau we calculate single end voltage crossing R2 in the above ca, the actual
differential voltage between Rx+ and Rx- is the double value of 300mV. i.e. it’s should be 0.6V. The following figure is the measured differential voltage on both PHY’s Rx side.
Vertical Amplitude = 0.600Vpp
This theory can be applied to other vendor’s PHY, if the other vendor’s PHY also provides
a current source.
5. How to Tune the Tx/Rx performance
•Resistor
生肖怎么读In order to achieve the better Rx performance of IP101G, we recommend the designer to t the resistors as R2=R4= 25 ohm ~ 30ohm.
Theoretically the designer does not need to tune the resistors, as long as the resistors are within the range.
We can derive the differential voltage on Rx+- is within the range between 450mV(min) and 650mV(max). But the actual measured value should be a little smaller than this, becau we ignore the loss of AC coupled capacitor in the calculation.
6. Connect to IP175C/D
IP101G connects to IP175C/D as the following application circuit.萝卜糕
0.1 uF
IP101G
Tx + or Rx+ or
IP101G PHY-to-PHY IP175C/D Circuit
香港回归作文
Tx - or
7. Connect to IP178G/IP175G
鸡犬相闻的意思
IP101G connects to IP178G/IP175G as the following application circuit.
0.1 uF
0.1 uF
自我管理技能IP101G IP178G/IP175G
Tx + or Rx+ or
IP101G PHY-to-PHY IP178G/IP175G Circuit
Tx - or Rx - or
(~ABOVE~)
