MAX19700EVKIT Maxim Integrated Products, MAX19700EVKIT Datasheet - Page 7

• Manufacturer Part Number: MAX19700EVKIT
• Description: EVAL KIT FOR MAX19700
• Manufacturer: Maxim Integrated Products
• Type: Encoder, Decoderr

Specifications of MAX19700EVKIT

• For Use With/related Products: MAX19700
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Access the MAX19700 auxiliary DACs through the
Auxiliary DACs tab of the MAX19700 EV kit software.
Set the output voltage of the desired auxiliary DAC by
adjusting the Aux-DAC 1, Aux-DAC 2, or Aux-DAC 3
sliders. Enter a number in the edit box below the slider
for precise adjustments. Enable each DAC by setting
the checkbox below the slider.
There are two methods for communicating with the
MAX19700: through the normal user-interface panel or
through the SPI commands available by selecting the
3-Wire Interface Diagnostic item from the Options
pulldown menu. A window is displayed that executes
an SPI read/write operation.
The SPI (3-wire interface) dialog box accepts numeric
data in hexadecimal format. Hexadecimal numbers
should be prefixed by a $ or 0x. Data entered in the
Data bytes to be written: edit box will be sent to the
device. Eight-bit hexadecimal numbers should be
comma-delimited. Data appearing in the Data bytes
received: box is data read from the device. As the
MAX19700 does not have an SPI read line, ignore any
data appearing in this box.
Clicking the Send Now button in Figure 3 transmits the
hexadecimal numbers 0x4A and 0xC1. 0x00 and 0x00
are the received values from the device. For a detailed
Figure 3. MAX19700 EV Kit Software 3-Wire Interface
Diagnostics
MAX19700 Evaluation Kit/Evaluation System
_______________________________________________________________________________________
Auxiliary DAC Controls
Simple SPI Commands
description of SPI communications with the MAX19700,
refer to the MAX19700 data sheet.
The MAX19700 EV kit is a fully assembled and tested
circuit board that contains all the components necessary
to evaluate the performance of the MAX19700 AFE IC.
The MAX19700 receive ADCs (Rx ADC) accept differ-
ential input signals; however, on-board transformers
(T1, T2) convert a readily available single-ended
source output to the required differential signal. The
input signals of the MAX19700 can be measured using
a differential oscilloscope probe at headers J4 and J7.
The MAX19700 transmit DACs (Tx DAC) are buffered
with on-board, ultra-low-distortion, split-supply opera-
tional amplifiers.
A bidirectional driver (U2) buffers and level-translates
the parallel data bus signals of the MAX19700. The par-
allel data bus of the MAX19700 EV kit is accessible at
header J11.
The EV kit is designed as a four-layer PC board to opti-
mize the performance of the MAX19700. Separate ana-
log, digital, clock, and buffer power planes minimize
noise coupling between analog and digital signals.
Differential 100Ω microstrip transmission lines are used
for analog ADC inputs and analog DAC outputs, while
50Ω microstrip transmission lines are used for all digital
outputs and the clock input. The trace lengths of the
ADC input and DAC output paths are well matched to
minimize layout-dependent input-signal skew.
For optimal performance, the MAX19700 EV kit requires
separate analog, digital, clock, and buffer power sup-
plies. Power supplies of +3.0V and +1.8V are recom-
mended to power the analog (VDD) and digital (OVDD)
portions of the MAX19700. A separate +3.3V power
supply (BVCC) is used to power the I/O level-translat-
ing buffer (U2). The clock circuitry (CVDD) is powered
by a +3.0V power supply. The DAC outputs of the
MAX19700 are buffered by split-supply op amps.
Power the positive rail (VOP) with a +5V supply. Power
the negative rail (VON) with a -5V supply.
Detailed Description of Hardware
Power Supplies
7