PHY-LINK Layer Interface Support
With versatile I/O capabilities and robust intellectual property (IP) cores, APEXTM II devices support physical link layer interfaces such as UTOPIA IV, POS-PHY Level 4, and Flexbus Level 4.
POS-PHY
The POS-PHY interface defines operations between physical layer devices (such as ATM, POS, and GigE framers) and link layer devices (such as asynchronous transfer mode (ATM), Internet protocol, and GigE forwarding devices). APEX II devices can support POS-PHY standards up to POS-PHY Level 4 (PL4). PL4 is a standard interface for switches and routers between a physical layer (PHY) and a link layer device, for aggregate bandwidths of OC-192 ATM and Packet-over-SONET (POS), as well as 10-Gigabit Ethernet applications. PL4 provides a flexible 10-Gbps system interface that can handle multiple protocols such as Ethernet, POS, and ATM, including a mix of ATM cells and packets simultaneously. Table 1 summarizes the APEX II POS-PHY link layer support.
| Table 1. POS-PHY Interface Support |
| Interface |
I/O Standard |
Maximum Throughput |
Channels |
Clock |
POS-PHY
Level 2 |
LVTTL |
622 Mbps |
16 |
50 MHz |
POS-PHY
Level 3 |
LVTTL |
2.5 Gbps |
8/32 |
104 MHz |
POS-PHY
Level 4 |
LVDS |
10 Gbps |
32 |
832 MHz |
UTOPIA
APEX II devices support the UTOPIA physical link (PHY-LINK) layer interface using the LVTTL and LVDS I/O standards. APEX II devices feature support for UTOPIA Level 1, Level 2, Level 3, and Level 4 interfaces, summarized in Table 2.
| Table 2. APEX II UTOPIA Interface Support |
| Interface |
I/O Standard |
Maximum Throughput |
Channels |
Clock |
UTOPIA
Level 1 |
LVTTL |
155 Mbps |
8 |
25 MHz |
UTOPIA
Level 2 |
LVTTL |
622 Mbps |
8/16 |
50 MHz |
UTOPIA
Level 3 |
LVTTL |
2.5 Gbps |
8/16/32 |
104 MHz |
UTOPIA
Level 4 |
LVDS |
10 Gbps |
32 |
415 MHz |
Flexbus
APEX II devices support AMCC's Flexbus Level 3 and Level 4 interfaces, as summarized in Table 3.
| Table 3. Flexbus Support |
| Interface |
I/O Standard |
Maximum Throughput |
Channels |
Clock |
Flexbus
Level 3 |
LVTTL |
2.5 Mbps |
32/64 |
50/100 MHz |
Flexbus
Level 4 |
HSTL Class I |
10 Gbps |
64 |
175 MHz |
|
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