Manuale d’uso / di manutenzione del prodotto DAC7741EVM del fabbricante Texas Instruments
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DAC7741EVM October 2002 DAP EVMs User ’ s G uide SLAU093.
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 input voltage range of ± 15 V and the output voltage range of ± 10 V . Exceeding the specified input range may cause unexpected operation and/or irreversible damage to the EVM.
Information About Cautions and Warnings iii Preface Read This First About This Manual This user ’ s guide describes the characteristics, operation, and the use of the DA7741 evaluation module. It covers all pertinent areas involved to properly use this EVM board along with the devices that it supports.
T rademarks iv Related Documentation From T exas Instruments T o obtain a copy of any of the following TI documents, call the T exas Instru- ments Literature Response Center at (800) 477 – 8924 or the Product Informa- tion Center (PIC) at (972) 644 – 5580.
Contents v Contents 1 EVM Overview 1-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Features 1-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents vi T ables 2-1 Parts List 2-7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 Factory Default Jumper Setting 3-2 . . . . . . . . . . . . . . . . . . .
1-1 EVM Overview EVM Overview This chapter gives a general overview of the DAC7741 evaluation module (EVM), and describes some of the factors that must be considered in using this module. T opic Page 1.1 Features 1-2 . . . . . . . . . . . . . . . . . .
Features 1-2 1.1 Features This EVM features the DAC7741 digital-to-analog converter . The DAC7741 EVM is a simple evaluation module designed for a quick and easy way to evaluate the functionality of the high resolution, single-channel, and parallel input DAC.
EVM Basic Functions 1-3 EVM Overview The REF102 precision reference derives its power of ± 15-V supply through J10 or J7 terminal. The (plus) 15 V connects through J10-1 or J7-2 terminals, while the (minus) -15 V connects through J10-3 or J7-4 terminals.
EVM Basic Functions 1-4 A block diagram of the EVM is shown below in the Figure 1-1. Figure 1-1. EVM Block Diagram DAC Out (J4) (J5) W13 Output Buffer Module W14 W4 W3 External Reference Module (J2) (.
2-1 Physical Description Physical Description This chapter describes the physical characteristics and PCB layout of the EVM and lists the components used on the module. T opic Page 2.1 PCB Layout 2-2 . . . . . . . . . . . . . . . . . . . . . . . . . .
PCB Layout 2-2 2.1 PCB Layout The EVM is constructed on a four-layer printed-circuit board using a copper-clad FR-4 laminate material. The printed-circuit board has a dimension of 99,06 mm (3.90 inch) × 104,14 mm (4.10 inch), and the board thickness is 1,57 mm (0.
PCB Layout 2-3 Physical Description Figure 2-2. Layer T wo (Ground Plane).
PCB Layout 2-4 Figure 2-3. Layer 3 (Power Plane).
PCB Layout 2-5 Physical Description Figure 2-4. Layer 4 (Bottom Plane).
PCB Layout 2-6 Figure 2-5. Drill Drawing.
Bill of Materials 2-7 Physical Description 2.2 Bill of Materials T able 2-1. Parts List Item # Qty Designator Manufacturer Part Number Description 1 1 C8 Panasonic ECJ3VB1C105K 1 µ F , 1206 multilayer ceramic capacitor 2 2 C9 C10 Panasonic ECUV1H103KBM 0.
Bill of Materials 2-8 (This page has been left blank intentionally .).
3-1 EVM Operation EVM Operation This chapter covers in detail the operation of the EVM to provide guidance to the user in evaluating the onboard DAC and how to interface the EVM to a specific host processor . Refer to the DAC7741 data sheet, SBAS248, for information about its parallel interface and other related topics.
Factory Default Setting 3-2 3.1 Factory Default Setting The EVM board is set to its default configuration from factory as described on th e table below to operate in bipolar ± 10V mode of operation using the internal reference.
Host Processor Operation 3-3 EVM Operation 3.2 Host Processor Operation The host processor basically drives the DAC, so the DACs proper operation depends on the successful configuration between the host processor and the EVM board. In addition, a properly written code is also required to operate the DAC.
Host Processor Operation 3-4 3.2.2 Output Gain of T wo This configuration allows the DAC output with a gain of two, but is limited to the effective rails of the operational amplifier . When the DAC7741 is configured to operate in bipolar mode, the DAC output must be within the range o f 1 2 V P- P or less.
Jumper Setting 3-5 EVM Operation 3.3 Jumper Setting The figures in T able 3-5 will show the function of each jumper on the EVM. T able 3-5. Jumper Setting Function Reference Jumper Setting Function 13 R OFFSET is strapped to V REF to set V SJ (summing junction) to V REF /2.
Jumper Setting 3-6 T able 3-5. Jumper Setting Function (Continued) Reference Jumper Setting Function Disconnects AGND from DGND. W1 1 Connects AGND and DGND together . 13 Positive supply rail of op-amp is powered by +15V . W12 13 Positive supply rail of op-amp is powered by V CC .
Schematic 3-7 EVM Operation 3.4 Schematic A schematic of the DAC7741 is found on the following page..
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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 Texas Instruments DAC7741EVM 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 Texas Instruments DAC7741EVM - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Texas Instruments DAC7741EVM imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Texas Instruments DAC7741EVM ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Texas Instruments DAC7741EVM, 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 Texas Instruments DAC7741EVM.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Texas Instruments DAC7741EVM. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Texas Instruments DAC7741EVM 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.
