CN8237EBGB Mindspeed Technologies, CN8237EBGB Datasheet - Page 71

• Manufacturer Part Number: CN8237EBGB
• Description: ATM SAR 622Mbps 3.3V ABR/CBR/GFR/UBR/VBR 456-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of CN8237EBGB

• Package: 456BGA
• Traffic Class: ABR|CBR|GFR|UBR|VBR
• Utopia Type: Level 1|Level 2
• Host Interface: PCI
• Maximum Data Rate: 622 Mbps
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3.135 V

28237-DSH-001-C
ATM backbone. Under worst case conditions, Ethernet packets (64 octets) map
into two ATM cells. At OC-12 rates, the CN8237 converts 706.4 k packets/second (kpps)
to cells in each direction. Therefore, the host must process control and status infor-
mation for a total of 1412.8 kpps. This packet rate equates to a packet
service time of 708 ns/packet.
An Ethernet Switch uses a CN8237 based subsystem as an uplink to an OC-12
3.0 Host Interface
3.1 Overview
The CN8237 segments and reassembles user data packets at over 600 Mbps full
duplex. The actual segmentation and reassembly processes execute without
run-time host control. However, the ATM host system supplies the data for
transmission and buffers for received data. In addition to this control, the host
processes status returned from the SAR. To take advantage of the CN8237’s high
throughput, the host must process control and status information at a comparable
rate.
performance requirements on the host system. High throughput systems require
large numbers of processing cycles and efficient utilization of system buses.
With this interface, the CN8237 facilitates a scalable, distributed host system. The
interface also minimizes the impact of an ATM port on the host system’s PCI bus.
In cases such as the example above, the service rate places extraordinary
The CN8237 provides a flexible, high performance host interface architecture.
APPLICATION EXAMPLE
Mindspeed Technologies
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