IDT77V107L25PFI IDT, Integrated Device Technology Inc, IDT77V107L25PFI Datasheet - Page 7

• Manufacturer Part Number: IDT77V107L25PFI
• Manufacturer: IDT, Integrated Device Technology Inc

Specifications of IDT77V107L25PFI

• Data Rate: 25.6/51.2Mbps
• Number Of Channels: 1
• Type Of Atm Phy Interface: UTOPIA
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (min): 3V
• Operating Supply Voltage (max): 3.6V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Pin Count: 100
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Not Compliant

errors, it does not attempt to correct them.
of the 4b/5b decoder uses feedback from the 4b/5b decoder to deter-
mine if it is not properly “framed” on the 5-bit symbols. If not properly
IDT77V107
Note that although the IDT77V107 can detect symbol and HEC
Upon resetting the device or re-establishing a serial link, logic in front
Rx +
Rx
UDF = User Defined Field (or HEC)
Figure 3 ATM Cell Format
Bit 7
Payload Byte 48
Payload Byte 1
Decoding
Header Byte 1
Header Byte 2
Header Byte 3
Header Byte 4
NRZI
Synthesizer
Line Clock
UDF
OSC
& PLL
Bit 0
3505 drw 52
5
.
Figure 4 TC Receive Block Diagram
Decoding
5b/4b
7 of 24
PHY-ATM
Interface
Control -
RECV
framed, it will shift its framing, one bit at a time, until it achieves proper
symbol framing. Receipt of an Escape (X) symbol will also force proper
symbol framing.
if the line is deemed 'bad'. The Interrupt Status Register contains a
Good Signal Bit (bit 6, set to 0 = Bad signal initially) which shows the
status of the line per the following algorithm:
To declare 'Good Signal' (from "Bad" to "Good"):
set to 7. When the clock ticks for 1,024 cycles (32MHz clock, 1,024
cycles = 204.8 symbols) and no "bad symbol" has been received, the
counter decreases by one. However, if at least one "bad symbol" is
detected during these 1,024 clocks, the counter is increased by one, to a
maximum of 7. The Good Signal Bit is set to 1 when this counter
reaches 0. The Good Signal Bit could be set to 1 as quickly as 1,433
symbols (204.8 x 7) if no bad symbols have been received.
3 Cells
The IDT77V107 monitors line conditions and can provide an interrupt
There is an up-down counter that counts from 7 to 0 and is initially
Start of Cell
4
4
RxRef
Command
Detection,
& Decode
Removal,
Byte
UTOPIA
Interface
Reset
4
4
Scramble
Scrambler
Nibble
PRNG
December 2004
De-
5362 drw 06
Next
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