1894K-40LFT IDT, 1894K-40LFT Datasheet - Page 28
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1894K-40LFT
Manufacturer Part Number
1894K-40LFT
Description
Ethernet ICs 3.3V 10/100 PHY RMII
Manufacturer
IDT
Datasheet
1.1894KI-40LFT.pdf
(53 pages)
Specifications of 1894K-40LFT
Rohs
yes
Part # Aliases
ICS1894K-40LFT
IDT® 10BASE-T/100BASE-TX INTEGRATED PHYCEIVER WITH RMII INTERFACE
Register
Register
25.15:12
ICS1894-40
10BASE-T/100BASE-TX INTEGRATED PHYCEIVER WITH RMII INTERFACE
25.11
25.10
25.9
25.8
25.7
25.6
25.5
25.4
25.3
25.2
25.1
25.0
Bit
Note 1:
Note 2:
Note 3:
† As per the IEEE Std 802.3u, during any write operation to any bit in this register, the STA must write the default value to all Reserved bits.
25 - Extended Control Register
26 - 31 - Extended Control Register (Reserved)
TX100BIAS_SET
TX10BIAS_SET
OUTDLY_CTL
Ignored if Auto negotiation is enabled.
CW = Command Override Write
LH = Latching High
LL = Latching Low
LMX = Latching Maximum
RO = Read Only
RW = Read/Write
RW/0 = Read/Write Zero
RW/1 = Read/Write One
SC = Self-clearing
SF = Special Functions
L = Latched on power-up/hardware reset
Definition
Reserved
Reserved
Add_Bias
RX_SET
Disable
The normal output current of the Bias block for
10BaseT is 540uA. Changing the register can modify
the current with a step size of 5%
000: output 80% current
001: output 85% current
010: output 90% current
011: output 95% current
100: output 100% current
101: output 105% current
110: output 110% current
111: output 115% current
The normal output current of the Bias block for
100BaseTX is 180uA. Changing the register can
modify the current with a step size of 5%
000: output 80% current
001: output 85% current
010: output 90% current
011: output 95% current
100: output 100% current
101: output 105% current
110: output 110% current
111: output 115% current
This register controls the delay time of the digital
control signal for xmit_dac.
00: Longest delay time (same as original design)
01: Long delay time
10: Short delay time
11: Shortest delay time
The output current of Bias block for RX block is
108µA. The register can change the current with a
step about 16.5%
00: Output 83.5% current
01: Output 100% current
10: Output 116.5% current
11: Output 133% current
Changing this value may modify the RX block
performance
When Bit = 0
Reserved
Reserved
Enable
When Bit = 1
28
Access
RW
RW
RW
RW
RW
RW
RW
2
SF
ICS1894-40
2
Default
0
0
1
1
0
0
1
0
0
0
0
1
PHYCEIVER
3
REV K 022412
Hex
0
6
4
1