Features: • AAL1 Segmentation and Reassembly device compliant with Circuit Emulation Services (CES) standard (af-vtoa-0078.000)
• Supports both Unstructured and Structured Circuit Emulation of 8 independent DS1/E1/STBUS interfaces
• Supports AAL1 trunking, with up to 128 TDM channels per VC (af-vtoa-0089.001)
• Supports CAS transmission and reception in all structured modes of operation
• Supports simultaneous processing of up to 256 bidirectional Virtual Circuits
• Supports mixed DS1/E1 operation
• Supports mixed Unstructured and Structured CES operation
• Fully flexible DS0 assignment
• Complete clock recovery solution provided onchip: Synchronous, Adaptive, or SynchronousApplication• B-ISDN (Broadband ISDN) systems requiring flexible N x 64 kbps transport
• Systems requiring af-vtoa-0078.000 (ATM Forum CES v2.0) "DS1 or E1 Nx64 Basic Service", "DS1 or E1 Nx64 Service with CAS", or "DS1 or E1 Unstructured Service" - flexible CES allows one-board solution to support multiple CES modes
• Systems requiring af-vtoa-0089.001 (ATM Forum - ATM Trunking Using AAL1 for Narrowband Services) -transport of up to 128 channels per VC
• DSLAM
• IAD
• Voice gateway
• NGDLC
• ATM Public Network access for PBX or CO
Specifications
| |
Parameter |
Symbol |
Min. |
Max. |
Units |
| 1 |
Supply Voltage - 2.5 Volt Rail |
VDD2 |
VSS |
3.5 |
V |
| 2 |
Supply Voltage - 3.3 Volt Rail |
VDD3 |
VSS |
4.5 |
V |
| 3 |
Voltage on 3.3 V Input pins |
VI3 |
- 0.5 |
6 |
V |
| 4 |
Voltage on 3.3 V Output pins |
VO3 |
- 0.5 |
4.6 |
V |
| 5 |
Continuous current at digital inputs |
II |
|
±10 |
mA |
| 6 |
Continuous current at digital outputs |
IO |
|
± 24 |
mA |
| 7 |
Storage Temperature |
TS |
- 40 |
+125 |
|
DescriptionThe MT90520 8-Port Primary Rate Circuit Emulation AAL1 SAR allows primary rate TDM circuits to be carried over ATM networks using Circuit Emulation Services. Up to 256 bidirectional ATM VC connections can be simultaneously processed by the MT90520 CES AAL1 SAR device.
The MT90520 supports several modes of Circuit Emulation Services for DS1 and E1 rates. These include Unstructured CES and Structured CES with and without Channel Associated Signalling (CAS).
On the TDM bus side, the MT90520 interfaces with 8 primary rate TDM ports operating at 1.544 Mbps or 2.048 Mbps. The configurable TDM ports interface directly with DS1 or E1 framers for Nx64 Structured operation, or with DS1 or E1 LIUs in Unstructured mode. On the ATM interface side, the MT90520 device meets the ATM Forum standard for UTOPIA Bus Level 2. The MT90520 is capable of operating as a UTOPIA "master" (ATM-end), "slave" (PHY-end), or "multi-PHY slave" (PHYend). The UTOPIA port can operate in 8-bit or 16-bit mode, with a clock rate up to 52 MHz.
Each of the eight ports of the MT90520 contains a PLL, allowing independent timing of each TDM port. Each PLL supports four modes of clock recovery: SRTS, Adaptive, Synchronous (from the Physical layer), or from the TDM line clock. Although a complete clock recovery solution is provided internally, an optional external PLL or external clock source is also supported.
MT90520 Data Sheet
