EVM Basic Functions
1-3
EVM Overview
buffered through U8A as seen by the device under test. The test points TP1,
TP2, and TP5 are also provided, as well as J4-18 and J4-20, to allow the user
to connect an external reference source, if the onboard reference circuit is not
desired. The external voltage reference should not exceed 5-V DC.
The REF02 precision reference is powered by V
CC
(15 V) through J1-3 or J6-1
terminal.
CAUTION
When applying an external voltage reference through TP1 or J4- 20,
make sure that it does not exceed 5 V maximum. Otherwise, this
can permanently damage the DAC8434, U1, device under test.
1.3
EVM Basic Functions
The DAC8534 EVM is designed primarily as a functional evaluation platform
to test certain functional characteristics of the DAC8534 digital-to-analog
converter. Functional evaluation of the DAC device can be accomplished with
the use of any microprocessor, TI DSP or some sort of a waveform generator.
The headers J2 and P2 are the connectors provided to allow the control signals
and data required to interface a host processor or waveform generator to the
DAC8534 EVM using a custom built cable.
A specific adapter interface card is also available for most of TI’s DSP starter
kits (DSK)—card models depend on the type of TI DSP starter kit. Therefore,
when requesting an adapter interface card be sure to specify the DSP in use.
In addition, a motherboard platform that is MSP430-microprocessor-based
can interface to this EVM, and is available. For more details or information
regarding the adapter interface card, or the MSP430 motherboard platform,
call Texas Instruments Inc. or e-mail us at
.
J4 allows for stacking EVMs and DAC output monitoring through selected
header pins. Stacking allows a total of eight DAC channels to be used,
provided the enable signals (EN) are unique to each EVM board stacked. All
outputs can be switched through their respective jumpers W2, W11, W12, and
W13.
In addition, the option of selecting one DAC output to be fed to the noninverting
side of the output op amp U2 is also possible by using a jumper across the
selected pins of J4. U2 must be first configured correctly for the desired
waveform characteristic—refer to Chapter 3 of this user’s guide.
A block diagram of the EVM is shown in the Figure 1 - 1.