
7. Recommended Interface Circuit (AC Coupling)
  | TXGND  | 
  | TxD  | 
Laser  | 
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Driver  | TxD  | 
9
R1
8
7
VCC SerDes
3.3V
R2
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R4  | |||||
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VCC
TX+
ECL/PECL
VCCTx  | 
Delta Transceiver | 
R3
6
  | C5  | R6  | 
  | R5  | |
L2  | VCC SerDes  | 
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TX-
DRIVER
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  | Signal detect  | 
  | SD  | |
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  | Pre-  | 
  | LIMITING  | 
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  | RxD  | |
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  | Am p  | Amplifier  | 
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  | RxD  | |
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  | RxGND  | |
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 C1
5
C2
4
3
2  | 
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1  | R7  | |
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3.3V  | 
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C3  | 
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L1  | 
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SD to upper leve l  | 
  | R10  | 
R13  | R9  | |
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C6  | R11  | 
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C7  | 
  | R12  | 
R8  | 
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Serializer/
Deserializer
RD-
  | Receiver  | 
RD+  | PLL etc. | 
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C1/2/3  | = 4.7 uF  | 
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C4/5/6/7  | = 100 nF  | 
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L1/2  | = 1 uH  | 
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R1/2  | =82 Ω (If C4/5=0, then R1/2 =130 Ω, it is for   | |
R3/4  | =130 Ω (If C4/5=0, then R3/4 =82 Ω, it is for   | |
R7/8  | =150 Ω  | 
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R5/6/9/10/11/12  | Depend on SerDes chip used  | |
R13  | = 270 Ω  | 
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Value of R5/6/9/10/11/12 may vary as long as proper 50 Ω termination or differential 100 Ω is provided. For good EMI performance, the power supply filter is required. Use shorter tracks from the inductor L1/2 to the module VccTx/VccRx .
5  | Revision: S2  | 
  | 03/09/2007  | 
DELTA ELECTRONICS, INC.  | www.deltaww.com  |