TZA3001A AN98098 OM5802 BLM11A102S ALARM3001 BLM21A102S TZA3001 L6/C10 C8/R10

TZA3001A minimized PCB layout AN98098 Philips Semiconductors TZA3001A minimized PCB layout Application Note AN98098 Abstract A

APPLICATION NOTE TZA3001A TZA3001A minimized PCB layout AN98098 AN98098 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout Application Note AN98098 AN98098 Abstract A minimized layout for a optical transmitter, consisting out of the TZA3001A TZA3001A laserdriver and a coax laser is presented. The the size of the PCB is 15.7x10.6 mm. © Philips Electronics N.V. 1998 All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any consequence of its use. Publication thereof does not convey nor imply any license under patent- or other industrial or intellectual property rights. 2 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout Application Note AN98098 AN98098 APPLICATION NOTE TZA3001A TZA3001A minimized PCB layout AN98098 AN98098 Author(s): Marcel J.M. Geurts Philips Semiconductors Systems Laboratory Eindhoven, The Netherlands Keywords TZA3001A TZA3001A SDH SONET FC GE Number of pages: 15 Date: 98-10-19 3 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout Application Note AN98098 AN98098 Summary A minimized layout for a optical transmitter, consisting out of the TZA3001A TZA3001A laserdriver and a coax laser is presented. The the size of the PCB is 15.7x10.6 mm2. 4 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout Application Note AN98098 AN98098 CONTENTS 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2. SCHEMATIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 3. LAYOUT INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4. DIMENSIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 5. COMPONENT PLACEMENT TOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 6. SIGNAL LAYER TOP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 7. SIGNAL LAYER BOTTOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 8. COMPONENT PLACEMENT BOTTOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 9. VIAS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout Application Note AN98098 AN98098 6 Philips Semiconductors TZA3001A TZA3001A minimized PCB layout 1. Application Note AN98098 AN98098 INTRODUCTION For the use of the TZA3001A TZA3001A laserdriver, customers can use the OM5802 OM5802 demoboard for design suggestions. However, for minimized application, the suggested layout had to be reworked. In order to give a suggestion in minimized applications, this apnote has been written. The apnote starts with a schematic, followed by the layout of each layer. 7 ALARMHI ALARMLO ONE ZERO L1 BLM11A102S BLM11A102S VCC_R VCC_R C1 R5 R4 R2 R3 ALARM3001 ALARM3001 22nF BFDSup L2 BLM11A102S BLM11A102S VCC_G C2 C7 100nF L5 BLM21A102S BLM21A102S ALS 29 30 31 32 C9 GND ALARMHI VCC ONE VCC LA ALARM MODE DINQ LAQ TZA3001 TZA3001 VCC GND IC1 ALS VCC_LAS ALARMLO (Opt. A) DIN GND GND 8 1 2 3 4 5 VCC 6 7 GND GND 28 VCC_R 6.3V 27 VCC GND BIAS VCC R8 100 22nF 26 ALARM BGAP VCC_R GND TZERO C6 C5 25 TONE VCC_B C4 100nF GND BLM11A102S BLM11A102S P1 ZERO GND VCC5V MONIN L4 GND VCC5V L3 BLM21A102S BLM21A102S R6 100 24 23 22 21 20 19 18 17 22nF 8 22nF 16 15 R7 24 C3 P2 14 13 C8 22nF Monitor anode BFD Monitor cathode 12 11 Laser cathode Laser anode 10 R10 9 VCC_Las R9 33 VCC_B VCC_G L6 C11 C12 47pF 22nF BFDSup BLM11A102S BLM11A102S C10 22nF BFD Application Note AN98098 AN98098 Schematics of transmitter. The supply domains are decoupled via a central lowpass filter (L3/C5) and individual filters for each domain (L1/C1, L2/C2, L4/C6, L5/C9, L6/C10 L6/C10). The data is AC coupled via C4 and C7, and terminated by R8. The set resistors for the optical "0" (R2), optical "1" (R3), alarm low level (R4) and alarm high level (R5) are connected to the VCC_R domain. The LA output is connected to the cathode of the laser (P2-2). The LAQ output is terminated with a dummy load (R9) to the supply of the laser (VCC_LAS to P2-3, Laser anode). The bias current flows via a 1206 shape resistor (R6, 1206 shape) for impedance increment of the bias source and removal of unnecessary power dissipation out of the IC. An equalization or pulse shape filter is foreseen as C8/R10 C8/R10. The bandgap voltage is decoupled with C12. The input of the monitor current (MONIN) must `see' 30 to 50 pF. Therefore an additional capacitor is placed at its input. All components are 0603 shape, except R6 (power dissipation) and C5 (value). Philips Semiconductors SCHEMATIC TZA3001A TZA3001A minimized PCB layout 2. viewing direction Component placement top Signal layer top PCB material: vias 9 Signal layer bottom Component placement bottom In order to maximize the heat flow from the IC it is strongly recommended to connect as much as possible metal area to the GND plane. Application Note AN98098 AN98098 The layout is viewed as seen from the top layer. A two layer PCB is foreseen. No attempts are made for matching of the line, since the lengths are minimized. Philips Semiconductors LAYOUT INFORMATION TZA3001A TZA3001A minimized PCB layout 3. Philips Semiconductors Units: mm TZA3001A TZA3001A minimized PCB layout DIMENSIONS 4. 10 Application Note AN98098 AN98098 11 Application Note AN98098 AN98098 Component placement top Philips Semiconductors TZA3001A TZA3001A minimized PCB layout COMPONENT PLACEMENT TOP 5. 12 Application Note AN98098 AN98098 Signal layer top Philips Semiconductors TZA3001A TZA3001A minimized PCB layout SIGNAL LAYER TOP 6. 13 Application Note AN98098 AN98098 Signal layer bottom Philips Semiconductors TZA3001A TZA3001A minimized PCB layout SIGNAL LAYER BOTTOM 7. 14 Application Note AN98098 AN98098 Component placement bottom Philips Semiconductors TZA3001A TZA3001A minimized PCB layout COMPONENT PLACEMENT BOTTOM 8. 15 Application Note AN98098 AN98098 Via Philips Semiconductors TZA3001A TZA3001A minimized PCB layout VIAS 9.