25g sfp28 direct attach cable (dac)
数据中心
sfp28 direct attach cables are compliant with sff-8432 and sff-8402 specifications. various choices of wire gauge are available from 30 to 26 awg with various choices of cable length (up to 5m).
• up to 25.78125 gbps data rate
• up to 5 meter transmission
• hot-pluggable sfp 20pin footprint
• improved pluggable form factor(ipf)
compliant for enhanced emi/emc
performance
• compatible to sfp28 msa
• compatible to sff-8402 and sff-8432
• temperature range: 0~ 70 °c
• rohs compatible
• cost-effective copper solution
• lowest total system power solution
• lowest total system emi solution
• optimized design for signal integrity
applications
• 25g ethernet
product description
• the sfp28 passive cable assemblies are high performance, cost effective i/o solutions for 25g ethernet. sfp28 copper cables allow hardware manufactures to achieve high port density, configurability and utilization at a very low cost and reduced power budget
parameter | symbol | min | typical | max | unit | note |
differential impedance | tdr | 90 | 100 | 110 | ώ | |
insertion loss | sdd21 | -22.48 | db | at 12.8906 ghz | ||
differential return loss | sdd11 sdd22 | see 1 | db | at 0.05 to 4.1 ghz | ||
see 2 | db | at 4.1 to 19 ghz | ||||
common-mode to common-mode output return loss | scc11 scc22 | -2 | db | at 0.2 to 19 ghz | ||
differential to common-mode return loss | scd11 scd22 | see 3 | db | at 0.01 to 12.89 ghz | ||
see 4 | at 12.89 to 19 ghz | |||||
differential to common mode conversion loss | scd21-il | -10 | db | at 0.01 to 12.89 ghz | ||
see 5 | at 12.89 to 15.7 ghz | |||||
-6.3 | at 15.7 to 19 ghz | |||||
notes: 1. reflection coefficient given by equation sdd11(db) < -16.5 2 × sqrt(f ), with f in ghz 2. reflection coefficient given by equation sdd11(db) < -10.66 14 × log10(f/5.5), with f in ghz 3. reflection coefficient given by equation scd11(db) < -22 (20/25.78)*f, with f in ghz 4. reflection coefficient given by equation scd11(db) < -15 (6/25.78)*f, with f in ghz 5. reflection coefficient given by equation scd21(db) < -27 (29/22)*f, with f in ghz
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pin descriptions
sfp28 pin function definition
pin | logic | symbol | name/description | notes | ||
1 | veet | transmitter ground | ||||
2 | lv-ttl-o | tx_fault | n/a | 1 | ||
3 | lv-ttl-i | tx_dis | transmitter disable | 2 | ||
4 | lv-ttl-i/o | sda | tow wire serial data | |||
5 | lv-ttl-i | scl | tow wire serial clock | |||
6 | mod_def0 | module present, connect to veet | ||||
7 | lv-ttl-i | rs0 | n/a | 1 | ||
8 | lv-ttl-o | los | los of signal | 2 | ||
9 | lv-ttl-i | rs1 | n/a | 1 | ||
10 | veer | reciever ground | ||||
11 | veer | reciever ground | ||||
12 | cml-o | rd- | reciever data inverted | |||
13 | cml-o | rd | reciever data non-inverted | |||
14 | veer | reciever ground | ||||
15 | vccr | reciever supply 3.3v | ||||
16 | vcct | transmitter supply 3.3v | ||||
17 | veet | transmitter ground | ||||
18 | cml-i | td | transmitter data non-inverted | |||
19 | cml_i | td- | transmitter data inverted | |||
20 | veet | transmitter ground | ||||
1. | signals not supported in sfp copper pulled-downto veet with 30k ohms resistor | |||||
2. | passive cable assemblies do not support | los and tx_dis |
mechanical specifications
the connector is compatible with the sff-8432 specification.
length (m) | cable awg |
1 | 30 |
2 | 30 |
3 | 30/26 |
4 | 26 |
5 | 26 |
feature | test method | performance |
electrostatic discharge (esd) to the electrical pins |
mil-std-883c method 3015.7 |
class 1(>2000 volts) |
electromagnetic interference(emi) | fcc class b | compliant with standards |
cenelec en55022 class b | ||
cispr22 ite class b | ||
rf immunity(rfi) |
iec61000-4-3 | typically show no measurable effect from a 10v/m field swept from 80 to 1000mhz |
rohs compliance | rohs directive 2011/65/eu and it's amendment directives 6/6 | rohs 6/6 compliant |
dac铜缆交换机sfp报价清单 | 规格参数 | 型号 | 单位 |
sfp28 25g dac cable | 1m | fgt-25gsfp28-dac1m | 根 |
sfp28 25g dac cable | 2m | fgt-25gsfp28-dac2m | 根 |
sfp28 25g dac cable | 3m | fgt-25gsfp28-dac3m | 根 |
sfp28 25g dac cable | 5m | fgt-25gsfp28-dac5m | 根 |