Specifications

Reference Design HFRD-25.2 (Rev.8; 01/09) Maxim Integrated Products
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Reference Design: Low-Cost GEPON SFF ONT with μC
Table of Contents
1. Overview .................................................... 2
2. Obtaining Additional Information .............. 2
3. Reference Design Device Details ............... 3
4. Functional Diagram .................................... 4
5. Recommended Operating Conditions......... 5
6. Typical Design Performance Data.............. 5
7. Transmitter Characteristic Graphs.............. 7
8. Receiver Characteristic Graphs .................. 18
9. Application Information ............................. 20
10. Controls/Features...................................... 21
11. Firmware................................................... 27
12. Evaluation Quick Start.............................. 36
13. SFF Module Pin Description .................... 38
14. Component List ........................................ 39
15. Schematics................................................ 40
16. Board Layout ............................................ 41
17. Layer Profile............................................. 42
Features
• Complete μC Firmware Provided
• Continuous or Burst Mode Operation
•
Monitors Bias Current, Photodiode
Current, V
CC
, RSSI (If Available) and
Temperature
•
Instant-On (Proper Modulation and Bias
Current by Second Burst)
•
Laser Driver, Limiting Amplifier and μC
Can Be Used in GEPON, BPON, or GPON
Applications
• Low-Cost Design
• Integrated PWM Compensation for V
CC
Variations
• Provides K-Factor and Linear
Temperature Compensation for
Modulation Current
1 Overview
High-Frequency Reference Design (HFRD) 25.2
is a low-cost GEPON SFF ONT module design
that provides excellent performance, features and
manufacturability. Material cost is minimized by
using low-cost components (laser driver, limiting
amplifier, microcontroller and optical
subassembly). To reduce assembly costs, all of the
components are placed on the top side of the PCB.
This low-cost design also provides excellent high-
speed performance and a rich set of features for
laser driver control and system monitoring.
The complete and fully documented firmware for
the μC is also provided to simplify integration and
custom modifications.
2 Obtaining Additional
Information
Only Gerber files for the GEPON ONT
transceiver board (HFRD-25.2) are available. For
more information please email to:
https://support.maxim-
ic.com/tech_support/submit_question.mvp?pl_id=
5.