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19-2404 Rev 0 6 / 01

MAX115 Evaluation Kit

19-2404 Rev 0 6 / 01
MAX115 Evaluation Kit
General Description
Features
Evaluates: MAX115 / MAX116
MAX115EVKIT / MAX116EVKIT Parts List
Ordering Information
TEMP. RANGE 0°C to +70°C 0°C to +70°C 0°C to +70°C 0°C to +70°C INTERFACE TYPE User-Supplied Windows Software User-Supplied Windows Software
MAX115EVB16 System Component List
PART MAX115EVKIT 68HC16 MOD16WIDE QTY 1 1 DESCRIPTION MAX115 Evaluation Kit 68HC16 µC Module with 16-bit parallel interface
MAX116EVB16 System Component List
DESCRIPTION MAX116 Evaluation Kit 68HC16 µC Module with 16-bit parallel interface
MAX115 EV Kit File List
INSTALL.EXE MAX115.EXE MAX115.HLP KIT125.B16 MAX115.INI UNINST.EXE Installs the EV kit files on your computer Application program Help file Software loaded into 68HC16 Program settings Removes the EV kit files from your computer
MAX115 Evaluation Kit Evaluates: MAX115 / MAX116
MAX115 Stand-Alone EV Kit
MAX115 EV System
Detailed Description of Software
The MAX115 digitizes up to four inputs from either the A or B input bank. Conversion time is determined by the number of enabled inputs. The software collects samples at a maximum throughput of 40ksps (one channel) to 26ksps (four channels). The various program functions are grouped into dialog boxes, which are accessible from the Window menu on the main menu bar.
Quick Start
Keyboard Navigation
If a mouse or other pointing device is not available, operate the program using the following keyboard shortcuts. Press ALT+W to bring up the Window menu and then select a tool window. Press the TAB key to select controls within the selected tool window. Buttons are activated by pressing the space bar. Check boxes, radio buttons, and combo boxes respond to the up / down arrow keys. Refer to Table 1, Keyboard Navigation Shortcuts.
1) Carefully connect the boards by aligning the two 40-pin headers of the MAX115 EV kit with the two 40-pin connectors of the 68HC16MOD-16WIDE module. Gently press them together. The two boards should be flush against one another. 2) Connect a +13V to +20V DC power source to the µC module at the terminal block located next to the
MAX115 Evaluation Kit
Table 1. Keyboard Navigation Shortcuts
KEY TAB ALT + W ALT + space ALT + minus Space Bar ALT + Print Screen Window menu System menu of main program window System menu of child window Click on the selected button Copy the image of main window onto the clipboard FUNCTION Select next control
Low-Speed Data Logging
Readings can be taken automatically from user-selected channels at regular intervals up to ten samples per second by selecting "Scan Tool" from the "Window"menu. The Channel Selection and Configuration group controls which channels shall be scanned, and (where applicable) configures each channel for bipolar and / or differential input. The Bipolar and Differential controls are disabled because the MAX115 inputs are always bipolar and never differential. The scan rate combo box controls the rate at which measurements are made. Readings are displayed in the Recent Values text area. Readings may optionally be recorded into a data log file. Click on the "New Log" button to begin or end data logging. This brings up the "Log File Format" dialog box. One complete line of data is written after all enabled channels have been sampled. The first line of the log file contains the column headings. Each subsequent line of the log file contains all enabled channels, separated by commas, tabs, or spaces (previously selected in the Log File Format dialog box). Once a log file has been opened, it can be paused or resumed with the corresponding Log menu commands. The program continues to write data to the log file until the Stop Log button is clicked.
the "Window" menu, select "Power Cycling Tool". The amount of power savings depends primarily on how long the part is off between conversions. The accuracy of the conversions depends on the power-up delay, the reference capacitor, and the time in power-down. Adjust the off-time with the delay between samples command. Adjust the on-time with the power-up delay command. Using an adequate power-up delay will ensure the desired conversion accuracy during power cycling modes. The reference must be allowed enough time to stabilize before the measurement is performed. Start with zero power-up delay and increase the delay time until no further change in accuracy is observed. The power-up delay requirement depends on the value of the reference capacitor and the off-time. The MAX115 EV kit software performs power-up by writing a configuration word with the shutdown bit set. After powering up, the power-up delay is executed to allow time for the reference voltage to stabilize so that an accurate measurement may be performed.
Evaluates: MAX115 / MAX116
Sampling Tool
To sample data at rates up to 40ksps (samples per second), select "Sampling Tool" from the "Window" menu, make your selections, and click on the Start button. The timing delays may be adjusted as appropriate to control the sample rate. The effective sample rate can be estimated by taking the reciprocal of the sum of the delay between samples, the power-up delay and the conversion time. Sample size is restricted to a power of two, so that the data can be processed by the FFT tool. The sample size control controls the number of samples collected on each selected channel. After the samples have been collected, the data is automatically uploaded to the host and is graphed. Once displayed, the data can optionally be saved to a file.
FFT Tool
The MAX115 evaluation software includes an FFT (Fast Fourier Transform) tool that can display the spectral content of data collected with the high-speed sampling tool. To view the spectral content of a waveform, first select a data sample that was previously collected with the high-speed sampling tool. Then, select "FFT Tool" from the "Window" menu. Check the output plots desired, and click on the Start button. A data windowing function preprocesses a data sample before performing the FFT. When the input signal is not synchronized to the sampling clock, spectral energy appears to leak into nearby frequency buckets. A suitable data
One-Shot Read Tool
The One-Shot Read Tool allows direct control of the A / D configuration. Select the channel and mode of operation to update the Control Byte display, or change the Control Byte bits directly and observe the change in the channel selection control. The Read Now button writes the configuration information to the A / D, and performs one reading.
Power Cycling Tool
To reduce average supply current demand, the MAX115 can be shut down between conversions. From
MAX115 Evaluation Kit Evaluates: MAX115 / MAX116
window tapers the raw data to zero amplitude at the beginning and end, reducing this spectral leakage. For more information on the fast fourier transform and data windowing functions, refer to W.H.Press et al, Numerical Recipes in Pascal: the Art of Scientific Computing, Cambridge University Press, 1989, ISBN 0521-37516-9. MAX115. CS8 is the chip-select output for the 7E800 memory-mapped I / O area, which the EV system uses to generate the conversion start strobe that signals the MAX115 to sample its inputs.
Measuring Supply Current
Device Characteristics
Troubleshooting
Problem: No output measurement. System seems to report zero voltage, or fails to make a measurement. Check +5V and -5V supply voltages. Check the 2.5V REFOUT reference voltage using a digital voltmeter. Use an oscilloscope to verify that the 16MHz clock is running and that the conversion-start signal is being strobed. Problem: Measurements are erratic, unstable poor accuracy. Check the reference voltage using a digital voltmeter. Use an oscilloscope to check for noise. When probing for noise, keep the oscilloscope ground return lead as short as possible, preferably less than 1 / 2 in (10mm). Problem: Inputs appear on wrong channels. Check the MAX115 clock pin with an oscilloscope. A crystal oscillator module with fast rise / fall times can overshoot or undershoot the power supply rails, violating device operation limits. Use a lowpass filter (such as R7 and C11 on the MAX115 EV kit) to eliminate clock overshoot.
Detailed Description of Hardware
P1-5 8 IN OUT GND GND N.C. 17 P2-1 A0 A1 D0 / A2 (LSB) D1 / A3 D2 D3 D4 D5 D6 CH4A 32 CH4A CLK 14 R7 10 8 25 CH4B 33 CH4B CH3A 34 CH3A +5V CH3B 35 CH3B CH2B 1 CH2B CH2A 2 CH2A CH1B 3 CH1B CH1A CH1A P2-2 P2-3 P2-4 P2-5 P2-6 P2-7 16 15 14 13 D7 D8 D9 +5V REFIN 6 C5 0.1µF REFOUT 7 C6 0.1µF REFOUT C7 4.7µF 6.3V 8 AGND AGND AVSS 31 36 DGND REFIN D10 D11 INT JU1 12 11 10 9 30 19 20 21 22 23 24 DVDD 4 AVDD 5 4 3 C2 0.1µF C1 0.1µF R8 10 2 GND GND N.C. +5V 7 C4 0.1µF 6 5 C3 10µF 25V 1
R1 100
U2 LM78L05ACM
Figure 1. MAX115 / MAX116 EV Kit Schematic
1 OE 2 A0 Y0 Y1 Y2 Y3 P2-14 P1-20 28 RD WR CS 27 +5V R3 10k +5V R2 10k 18 29 CONVST 26 R4 10k +5V 9 7 5 3 12 R5 10k P2-13 14 P2-12 16 +5V P2-11 A1 A2 A3 74HCT244 4 6 8 18 P2-10 P2-9 P2-8
CS7 / 7E000
P1-35
P1-38
1 U5 16MHz 7 OSCILLATOR C11 100pF
P1-37
MAX115 MAX116
CS8 / 7E800
P1-36
19 OE A0 Y0 Y1 Y2 Y3 A1 A2 A3 74HCT244 11 13 15 17
R6 100 8 N.C. OUT IN IN N.C. IN IN GND 7 C8 10µF 25V C9 0.1µF 6 5 2 3 4 1
U4 LM79L05ACM
P1-1 P1-2 -5V C10 0.1µF P1-3 P1-4 GND
Evaluates: MAX115 / MAX116
MAX115 Evaluation Kit
MAX115 Evaluation Kit Evaluates: MAX115 / MAX116
Figure 2. MAX115 / MAX116 EV Kit Component Placement Guide
Figure 3. MAX115 / MAX116 EV Kit PC Board Layout - Component Side
MAX115 Evaluation Kit Evaluates: MAX115 / MAX116
Figure 4. MAX115 / MAX116 EV Kit PC Board Layout - Solder Side
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