R-IN32M4-CL3 User's Manual: Board design edition
6. Gigabit Ethernet PHY Pins
R18UZ0074EJ0100
Page 16 of 61
Dec 24, 2019
6.2.2
Recommended Components
We recommend using pulse transformer that satisfy the following conditions.
We also recommend the constitution illustrated in Transformer of Figure 6.3.
Common-mode chokes are not required on the R-IN32M4-CL3 (PHY side) and is mounted on the connector.
Winding ratio: 1:1 (
2% or less, or
3%) recommended
Return loss (see Figure 6.4): -18dB or less (from 1.0 MHz to 40 MHz)
-(12-20log(f/80))dB or less (from 40 MHz to 100 MHz) *f: Frequency
Caution:
We recommend as little variation in return loss from 1.0 MHz to 40 MHz as possible.
The impedance is 85, 100, or 115
.
For details, contact the corresponding manufacturer.
Figure 6.4 Example of Return Loss of Pulse Transformer
Recommended components of the pulse transformer as listed below.
Manufacturer
Product Type Name
Pulse
H5008NL