Manuale d’uso / di manutenzione del prodotto M-LVDS del fabbricante Compaq
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Multipoint-Low V oltage Dif fer ential S ignaling (M-L VDS) E valuation Module April 2004 High Performance Analog User ’ s G uide SLLU039B.
IMPORT ANT NOTICE T exas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications, enhancements, improvements, and other changes to its products and services at any time and to discontinue any product or service without notice.
EVM IMPORT ANT NOTICE T exas Instruments (TI) provides the enclosed product(s) under the following conditions: This evaluation kit being sold by TI is intended for use for ENGINEERING DEVELOPMENT OR EV ALUA TION PURPOSES ONL Y and is not considered by TI to be fit for commercial use.
EVM W ARNINGS AND RESTRICTIONS It is important to operate this EVM within the supply voltage range of 3 V to 3.6 V . Exceeding the specified supply range may cause unexpected operation and/or irreversible damage to the EVM.
v Read This First Preface How to Use This Manual This document contains the following chapters: - Chapter 1 — The M-L VDS Evaluation Module - Chapter 2 — T est Setup - Chapter 3 — Bill of Materi.
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Running Title — Attribute Reference vii Chapter Title — Attribute Reference Contents 1 The M-L VDS Evaluation Module 1-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Overview 1-2 . . . . .
Running Title — Attribute Reference viii Figures 1 − 1. M-L VDS Unit Interval Definition 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 − 2. Expanded Graph of Receiver Dif ferential Input V oltage Showing T ransition Region 1-4 .
1-1 The M-L VDS Evaluation Module The M-L VDS Evaluation Module This document describes the multipoint low-voltage differential-signaling (M-L VDS) evaluation module (EVM) used to aid designers in development and analysis of this new signaling technology .
Overview 1-2 The M-L VDS Evaluation Module 1.1 Overview The EVM comes with all the production devices in T able 1 − 1. The SN65ML VD201 and SN65ML VD207 are installed on the circuit board, and ca n easily be replaced with the other devices supplied.
M-L VDS Standard TIA/EIA − 899 1-3 The M-L VDS Evaluation Module The EVM has been designed with the individual driver and receiver section (SN75ALS180 footprint, U1) on one half of the board and the transceiver section (SN75176 footprint, U2) on the other half (see Figure 3 − 1).
M-L VDS EVM Kit Contents 1-4 The M-L VDS Evaluation Module T able 1 − 2. Receiver Input V oltage Threshold Requirements Receiver T ype Low High T ype-1 − 2.4 V ≤ V ID ≤ − 0.05 V 0.05 V ≤ V ID ≤ 2.4 V T ype-2 − 2.4 V ≤ V ID ≤ 0.05 V 0.
Configurations 1-5 The M-L VDS Evaluation Module 1.4 Configurations The M-L VDS EVM board allows the user to construct various bus configurations. The two devices on the EVM allow for point-to-point simplex, parallel-terminated point-to-point simplex, and two-node multipoint operation.
Configurations 1-6 The M-L VDS Evaluation Module 1.4.2 Multidrop A multidrop configuration (see Figure 1 − 5) with two receiver nodes can be simulated with the EVM.
Configurations 1-7 The M-L VDS Evaluation Module Figure 1 − 7. T wo-Node Multipoint Circuit T U1 U2 T 1.4.4 EVM Operation With Separate Power Supplies The EVM has been designed with independent power planes for the two devices. The two devices can be powered with independent supplies or with a single supply .
Recommended Equipment 1-8 The M-L VDS Evaluation Module Figure 1 − 8. EVM Configuration for Including a Ground Potential Difference V oltage Between Nodes PS1 PS2 PS3 Jumpers removed from W7, W8, W9, W10 W9 W7 W8 W10 J13 J14 J17 J18 + − + − + − 1.
2-1 T est Setup T est Setup This chapter describes how to setup and use the M-L VDS EVM. T opic Page 2.1 T ypical Cable T est Configurations 2-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 T est Results 2-5 . . . . . . . . . . . . .
T ypical Cable T est Configurations 2-2 T est Setup 2.1 T ypical Cable T est Configurations Each of the following test configurations is a transmission line consisting of a twisted-pair cable connected on the 2-pin connectors (P1, P2, or P3). T able 2 − 1 shows the possible configurations.
T ypical Cable T est Configurations 2-3 T est Setup 2.1.2 Point-to-Point Parallel T erminated Simplex T ransmission 1) Connect a twisted-pair cable from P1 to P2. 2) V erify resistor R4 and R7 are installed. 3) Remove resistors R5 and R6. This properly terminates the transmission line at both ends.
T ypical Cable T est Configurations 2-4 T est Setup Figure 2 − 3. T wo-Node Multipoint T ransmission R16 100 P3 R3 49.9 R5 100 U1 R7 100 R6 100 J2 9 10 5 P2 T wisted Pair Cable Input Signal R14 49.
T est Results 2-5 T est Setup 2.2 T est Results The test configurations described in Section 2.1 were used to simulate point- to-point simplex, parallel-terminated point-to-point simplex, and two-node multipoint. The test results are shown in the following figures.
T est Results 2-6 T est Setup signal on TP1, R2 is shorted. T ype-2 behavior is again observed on the SN65ML VD207 receiver output. T race three shows the differential voltage on the bus. Note that the bus volt- ages are nominal M-L VDS levels of 1.1 V PP due to the lower load seen by the current driver .
3-1 Bill of Materials, Board Layout, and PCB Construction Bill of Materials, Board Layout, and PCB Construction This chapter contains the bill of materials, board layout of the M-L VDS, and describes the printed-circuit board. T opic Page 2.1 Bill of Materials 3-2 .
Bill of Materials 3-2 Bill of Materials, Board Layout, and PCB Construction 3.1 Bill of Materials T able 3 − 1. M-L VDS EVM Bill of Materials Item No. Qty . Reference Designation Description MFG Part # Not Installed 1 2 C1, C2 Capacitor , SMT1206, 50 V , 10%, 0.
Board Layout 3-3 Bill of Materials, Board Layout, and PCB Construction 3.2 Board Layout Figure 3 − 1. Assembly Drawing GND01 VCC01 VCC GND VCC01 GND01 GND VCC VCC GND GND01 VCC01 TEXAS INSTRUMENTS A/W NO. # 6424409B PW A. EVM. SN65ML VD SERIAL NO. MADE IN U.
Board Layout 3-4 Bill of Materials, Board Layout, and PCB Construction The second layer of the EVM has the separate ground planes. These are the reference planes for the controlled impedance traces on the top layer . Figure 3 − 3. Second Layer The third layer of the EVM has the power planes.
Board Layout 3-5 Bill of Materials, Board Layout, and PCB Construction The bottom layer of the EVM contains bulk and decoupling capacitors to be placed close to the power and ground pins on the device.
PCB Construction 3-6 Bill of Materials, Board Layout, and PCB Construction 3.3 PCB Construction Information in this section was obtained from the following source: - Electromagnetic Compatibility Printed Circuit Board and Electronic Module Design, VEC workshop, V iolette Engineering Corporation.
PCB Construction 3-7 Bill of Materials, Board Layout, and PCB Construction Figure 3 − 6. T race Configurations in Printed-Circuit Boards MICROSTRIP STRIPLINE Board Material W h t W t W S Stripline construction is the preferred configuration for differential signaling.
PCB Construction 3-8 Bill of Materials, Board Layout, and PCB Construction T able 3 − 2 shows the layer stack up of the EVM with the defined trace widths for the controlled impedance etch runs using microstrip construction. T able 3 − 2. EVM Layer Stack Up Differential Model Single-Ended Model Material T ype: FR 406 Layer No.
A-1 Schematic Schematic This Appendix contains the EVM schematic. Appendix A.
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Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Compaq M-LVDS è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Compaq M-LVDS - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Compaq M-LVDS imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Compaq M-LVDS ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Compaq M-LVDS, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Compaq M-LVDS.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Compaq M-LVDS. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Compaq M-LVDS insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
