Maxim Integrated MAX1415 User Manual
General Description
The MAX1416 evaluation kit (EV kit) is an assembled and
tested circuit board that demonstrates the MAX1416
multichannel, 16-bit, sigma-delta data-acquisition system.
Windows®98/2000/XP software provides a convenient
user interface to exercise the features of the MAX1416.
Order the complete evaluation system (EV system)
(MAX1416EVC16) for a comprehensive evaluation of the
MAX1416 using a personal computer. Order the EV kit
(MAX1416EVKIT) if the 68HC16MODULE-DIP has been
purchased with a previous Maxim EV system, or for custom use in other microcontroller (µC)-based systems.
To evaluate the MAX1415, request a free sample of the
MAX1415EUE. To evaluate the MX7705, request a free
sample of the MX7705EUE.
Features
♦ Proven PC Board Layout
♦ Complete Evaluation System
♦ Convenient On-Board Test Points
♦ Fully Assembled and Tested
Evaluates: MAX1416/MAX1415/MX7705
MAX1416 Evaluation Kit/
Evaluation System
________________________________________________________________ Maxim Integrated Products 1
19-3084; Rev 0; 12/03
MAX1416EVC16 System
Component List
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
MAX1416EVKIT Parts List
Windows is a registered trademark of Microsoft Corp.
PART
INTERFACE TYPE
MAX1416EVC16
Windows software
MAX1416EVKIT
User supplied
Note: The MAX1416 software is designed for use with the complete EV system (MAX1416EVC16). It includes a 68HC16MODULE-DIP module and a MAX1416EVKIT. If the MAX1416 evaluation software is not used, the MAX1416EVKIT board can be purchased by itself, without the µC.
PART QTY DESCRIPTION
MAX1416EVKIT 1 MAX1416 evaluation kit
68HC16MODULE-DIP
1 68HC16 µC module
REFERENCE QTY DESCRIPTION
C1–C4, C10,
C11
C5 1
C6 1
C7, C8 2
C9, C12, C13 3
C14 1
0.01µF, 10V X7R ceramic capacitors
6
(radial leaded)
0.01µF ±10%, 50V X7R ceramic
capacitor (0603)
Taiyo Yuden UMK107B103KZ
TDK C1608X7R1H103KT
4.7µF ±20%, 10V X5R ceramic
capacitor (1206)
Taiyo Yuden LMK316BJ475ML
TDK C3216X5R1A475MT
22pF ±5%, 50V C0G ceramic
capacitors (0603)
TDK C1608C0G1H220J
0.1µF ±10%, 50V X7R ceramic
capacitors (0805)
Taiyo Yuden UMK212BJ104KG
TDK C2012X7R1H104KT
1µF, 10V X7R ceramic capacitor
(0805)
TDK C2012X7R1A105K
TEMP RANGE
0°C to +70°C
0°C to +70°C
REFERENCE QTY DESCRIPTION
H1 1 8-pin header
J1 1 2 x 20 right-angle socket
JU1 1 2-pin header
JU2 1 2-pin header
JU3 1 3-pin header
JU4 1 2-pin header
JU1–JU4 4 Shunts
R1–R4 4 10Ω ±5% resistors (axial leaded)
R5, R6 2 10Ω ±5% resistors (1206)
TB1 1
TB2, TB3 2
U1 1 MAX1416EUE
U2 1 MAX873ACSA
U3, U4 2 MAX1840EUB
Y1 1
None 1 MAX1416 PC board
None 1
0.200in 2-circuit screw terminal
0.200in 3-circuit screw terminal
blocks
4.9152MHz crystal (HC49/US),
parallel resonant, 20pF load
ECS 49-20-4
Software disk, MAX1416
Evaluation Kit
Evaluates: MAX1416/MAX1415/MX7705
MAX1416 Evaluation Kit/
Evaluation System
2 _______________________________________________________________________________________
Component Suppliers
SUPPLIER PHONE FAX WEBSITE
Taiyo Yuden 800-348-2496 847-925-0899 www.t-yuden.com
TDK 847-803-6100 847-390-4405 www.component.tdk.com
Note: Please indicate that you are using the MAX1416 when contacting these component suppliers.
Quick Start
Required Equipment
Before you begin, you need the following equipment:
• MAX1416EVC16 (contains a MAX1416EVKIT board
and a 68HC16MODULE-DIP)
• DC power supply, +7VDC to +12VDC at 0.25A
• DC power supply, +5VDC
• Windows 98/2000/XP computer with an available serial
(COM) port
• 9-pin I/O extension cable
Procedure
Do not turn on the power until all connections are
completed.
1) Ensure that JU1, JU2, and JU4 are closed, and that
JU3 is in the 1-2 position (see Table 1 for jumper
settings).
2) Carefully connect the boards by aligning the 40-pin
header of the MAX1416 EV kit with the 40-pin connector of the 68HC16MODULE-DIP module. Gently
press them together. The two boards should be
flush against one another.
3) Connect the +5VDC power source to the MAX1416
EV kit at terminal block TB1. Observe the polarity
marked on the board.
4) Connect the +7VDC to +20VDC power source to
the µC module at the terminal block located next to
the on/off switch, along the top edge of the µC
module. Observe the polarity marked on the board.
5) Connect a cable from the computer’s serial port to
the µC module. If using a 9-pin serial port, use a
straight-through, 9-pin female-to-male cable. If the
only available serial port uses a 25-pin connector, a
standard 25-pin to 9-pin adapter is required. The
EV kit software checks the modem status lines
(CTS, DSR, DCD) to confirm that the correct port
has been selected.
6) Install the evaluation software on your computer by
running the INSTALL.EXE program on the disk. The
program files are copied and icons are created for
them in the Windows Start menu.
7) Turn on the power supply.
8) Start the MAX1416 program by clicking on its icon
in the Start menu.
9) The program prompts you to connect the µC module and to turn on its power. Slide SW1 to the ON
position. Select the correct serial port, and click
OK. The program automatically downloads its software to the module.
10) When the main window appears (Figure 1), click
Initialize and then Calibrate.
11) Apply input signals between AIN1+ and AIN1-. Tie
the unused analog input AIN2+ and AIN2- to GND.
Click Read or check Auto Read. Observe the code
and voltage readout on the screen.
Detailed Description
of Software
The main window of the evaluation software controls the
features of the MAX1416. The Measurement tab sheet is
used to initialize, calibrate, and read data. Prior to reading the MAX1416, select the appropriate MCLK masterclock input source and click Initialize. The FS1 and FS0
bits in the clock register determine the data rate.
The Initialize button writes the clock register INT,
CLKDIS, CLKDIV, CLK, and FS bits, and then writes to
the setup register with FSYNC = 1. The exact value
written to the clock register depends on the MCLK
input setting, and can be viewed by bringing up the
Clock tab sheet after initialization.
The Calibrate button first writes the setup register with
FSYNC = 1, then writes setup with MD = 01 (self-calibration mode) and FSYNC = 0. After DRDY returns low,
the MAX1416 setup register automatically returns to
MD = 00 and FSYNC = 0.
The Setup, Clock, Offset, and Gain tab sheets provide
read/ write access to each of the registers. See
Figures 2–5.
The Comms and Data (Figure 6) tab sheet provides
access to the Standby bit. The comms registers RS2,
RS1, RS0, and R/W bits are automatically set by each
register’s read and write buttons. The channel select
bits CH1 and CH0 are determined by which channel is
selected on the Measurement tab sheet.
Sampling
To collect data, go to the Measurement tab sheet and
click Sample. Select the sample size and click Begin
Sampling. After the samples have been collected, the
data is automatically uploaded to the host and is
graphed. Once displayed, the data can be saved to a
file (optional).
Saving Graphs to Disk
Data in the real-time graph and in the sampled data
graphs can be saved to a file (Figures 7–8). Only the
raw output codes are saved, but voltages can be
inferred based on the reference voltage and the maximum code value.
Evaluating Power-Down Mode
To enter standby mode, first make sure that Auto Read
is not checked in the Measurement tab sheet. Then go
to the Comms and Data tab sheet and check power-
down, then click write.
Reference Voltage
The evaluation software assumes a 2.500V reference
voltage, unless otherwise specified. To override this
value, go to the Measurement tab sheet and type the
new reference voltage next to REF voltage.
Software Listing
The EV kit software disk contains the driver source and
header file. Refer to DRV1416.cpp and DRV1416.h.
Detailed Description
of Hardware
The MAX1416 (U1) is a multichannel, 16-bit, sigmadelta data-acquisition system. Resistors R1–R4 and
C1–C4 act as anti-aliasing filters. The MAX873 (U2) is a
2.5V reference. C14 ensures the MAX873’s stability for
arbitrary values of input capacitor C11. Level translators U3 and U4 allow the kit to support the 3V
MAX1415, as well as the 5V MAX1416. The input signal
can be applied directly to terminal blocks TB2 and TB3.
C5 and C6 bypass the analog-to-digital converter’s
power supply. See Figure 9, and refer to the MAX1416
data sheet.
Evaluating the MAX1415
To evaluate the MAX1415, request a free sample of the
MAX1415EUE and replace U1. Follow the Quick Start
procedure, with the following exceptions:
• In step 1, leave JU1 and JU2 open.
• In step 3, apply a +3VDC power supply (instead of
+5V) to TB1. Apply an external +1.225VDC differential reference between TB3 pins 3 and 2.
• After step 10, go to the software’s Measurement tab
sheet and type the new reference voltage of 1.225
next to REF voltage.
Evaluating the MX7705
To evaluate the MX7705, request a free sample of the
MX7705EUE and replace U1. The MX7705 is similar to
the MAX1415/1416 except it does not support internal
clock mode (INT must always be zero).
Using an External Reference
To use an external reference, remove the shunts from
JU1 and JU2, and connect a differential reference
between TB3 pins 3 and 2. The evaluation software
assumes a 2.500V reference voltage, unless otherwise
specified. To override this value, go to the Measurement
tab sheet and type the new reference voltage next to
REF voltage.
Troubleshooting
Problem: No output measurement. System seems to
report zero voltage, or fails to make a measurement.
Check VDD supply voltage at TB1. The EV kit requires
a separate supply in addition to the supply on the
microcontroller module. Check the reference voltage
using a digital voltmeter. Use an oscilloscope to verify
that the CS, SCLK, and DIN waveforms are correct. If
the DRDY signal is pulsing, then the software has successfully initialized the MAX1416 and conversions have
been triggered.
Problem: Cannot see MCLK waveform on oscilloscope.
When using an external crystal, the MCLKIN and
MCLKOUT nodes are very sensitive to extra load
capacitance. Connecting a typical 10x scope probe
effectively doubles the load capacitance from 20pF to
40pF, which can slow down or even halt oscillation.
When using the internal oscillator (clock register INT =
1 and CLKDIS = 0), the oscillator signal is visible on the
MCLKOUT pin. In this mode, MCLKOUT can be measured using a typical 10x scope probe.
Evaluates: MAX1416/MAX1415/MX7705
MAX1416 Evaluation Kit/
Evaluation System
_______________________________________________________________________________________ 3
Evaluates: MAX1416/MAX1415/MX7705
Problem: Internal oscillator does not work.
The internal-oscillator mode is a feature of the
MAX1416/MAX1415 only, and is not supported on the
MX7705. The MX7705 requires an external clock, and
can only be used with INT = 0. To observe the internal
oscillator driving the MCLKOUT pin, U1 must be a
MAX1416 or MAX1415, and the clock register must
have INT = 1 and CLKDIS = 0.
Problem: Measurements are erratic or unstable or
there is 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: Unacceptable errors when measuring a
transducer.
Although most signal sources can be connected directly to the MAX1416’s analog input, some high-impedance signal sources may require using the internal
input buffer (BUF = 1).
Problem: PDA hot-sync software or other device software interferes with EV kit software.
COM ports can only be used by one device at a time.
Disable PDA hot-sync manager.
MAX1416 Evaluation Kit/
Evaluation System
4 _______________________________________________________________________________________
QSPI is a trademark of Motorola, Inc.
Table 1. Jumper Functions
JUMPER
SHUNT
FUNCTION
Closed*
U2 (MAX873) supplies REF+
reference voltage
JU1
Open REF+ must be externally connected
Closed* REF- connects to ground at U2
JU2
Open REF- must be externally connected
1-2* MCLKIN connects to crystal Y1
Open MCLKIN is not connected
JU3
2-3
MCLKIN connects to ground
(MAX1416/MAX1415 internaloscillator mode only)
Closed* MCLKOUT drives crystal Y1
JU4
Open
MCLKOUT is not connected
(MAX1416/MAX1415 internaloscillator mode only)
*Default configuration
POSITION
Evaluates: MAX1416/MAX1415/MX7705
MAX1416 Evaluation Kit/
Evaluation System
_______________________________________________________________________________________ 5
Figure 1. MAX1416—Main Window of the Evaluation Software—Measurement Tab Sheet
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