10/100 Non-PCI Ethernet Single Chip MAC + PHY
Datasheet
REFERENCE
TIME (NS) INTERNAL MAU
VOLTAGE (V)
Q
R
S
111
111
111
110
100
110
90
0.15
0
-0.15
-1.0
-0.3
-0.7
-0.7
T
U
V
W
Transmit Level Adjust
The transmit output current level is derived from an internal reference voltage and the external resistor
on RBIAS pin. The transmit level can be adjusted with either (1) the external resistor on the RBIAS
pin, or (2) the four transmit level adjust bits in the PHY Ml serial port Configuration 1 register as shown
in Table 7.2. The adjustment range is approximately -14% to +16% in 2% steps.
Table 7.2 Transmit Level Adjust
TLVL[3:0]
GAIN
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
1.16
1.14
1.12
1.10
1.08
1.06
1.04
1.02
1.00
0.98
0.96
0.94
0.92
0.90
0.88
0.86
Transmit Rise and Fall Time Adjust
The transmit output rise and fall time can be adjusted with the two transmit rise/fall time adjust bits in
the PHY Ml serial port Configuration 1. The adjustment range is -0.25ns to +0.5ns in 0.25ns steps.
SMSC LAN91C111-REV B
Revision 1.8 (07-13-05)
DATA4S1HEET
SMSC [ SMSC CORPORATION ]
