Transcript ppt
Gigabit Ethernet – IEEE 802.3z The Choice of a New Generation Design Presentation ECE 4006c G2- Gigabit Ethernet Intel/Agilent TX Javier Alvarez, gte006r Astou Thiongane, gt3083a Ebrima Kujabi, gte212s Objectives General Use – MAXIM 3287 Kit Board Specs – Basic Features – Component Analysis – Safety Features – Issues with Laser Mounting Testing Procedures Design Board General Use of MAXIM board Remove transceiver Module from Intel PRO/1000 Board. Replace transmitter with MAXIM 3287 – Optical Transmitter Module Board Specs Basic Features – Optimized operation at 1.25 Gbps. – Supports a current modulation up to 30mA. – Deterministic Jitter of approx. 22 ps. – Requires a 3.3 V to 5V power supply. Component Analysis Differential Input & Output – Eliminates noise in channel Reference Voltage – Used for programming a laser bias current in VCSEL applications (~0.8mA) Monitor Diode – Monitors Laser Current – Not supported by board Component Analysis (Cont’d) Current Modulation Control (Pin 15) Temperature Coefficient Control (Pin 16) Laser Mounting VCSEL Mounting – Common-Cathode Configuration Avoiding Laser Ringing or Overshooting – Reduce Length of Leads – Typical Package Leads have inductances of 25nH/in. Common-Cathode Configuration Safety Features Shutdown Driver Output (SHDNDRV) Power-On Reset (POR) – Resets Laser when turned off. – Rejects Noise caused by VCC during power-on or hot plugging. Bias Controlling Transistor Driver (BIASDRV) – Transistor placed between BIASDRV and VCC – Ensures Low Noise Operation – Rejects Power Supply Noise Decoupling Capacitors at VCC & GND Testing Procedures The Eye Mask from IEEE 802.3z – Distinction between logical 1 and 0 – Allows to see amount of jitter Bit Error Testing – Tektronic BERT Testbed Board Design Parts List Consists: – VCSEL (~850 nm) – SMA Connectors – SMA Cable – Resistors – Capacitors – Inductors – 3 to 5 Volt Power Supply Picture provided by: http://www.ece.gatech.edu/academic/courses/fall2001/ece4006/1G2/