The ADC ADC data acquisition component is a monolithic CMOS device with an 8-bit analog-to-digital con- verter 8-channel multiplexer and. ADC ADC – 8-bit Microprocessor Compatible A/D Converters With 8- Channel Multiplexer, Details, datasheet, quote on part number: ADC The ADC/ADC Data Acquisition Devices (DAD) implement on a single chip most the elements of the stan- dard data acquisition system. They contain.
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Source code The source code consists of a few of files. The voltage level that, when received as an input, will output “” to the FPGA. The maximum clock frequency is affected by the source impedance of the analog inputs. The ADC stores the data in a tri-state output latch until the next conversion is started, but the data is only output when enabled.
For a quick reference refer to table 2. There are 8, 8 clock cycle periods required in order to complete an entire conversion. It goes low when a conversion is started and high at the end of a conversion. It is a control signal from adtasheet FPGA, which tells the converter when to start a conversion. Note that it can take up to 2.
Address Lines Because the chip has an 8 channel multiplexer there are three address select lines: Start The purpose of the start signal is two fold. All of the signals are explained below. The clock should conform to the same range as all other control signals. The OE signal should conform to the same range as all the other control signals.
Unfortunately you cannot just hook up analog inputs to an ADC and expect to get digital outputs from the chip without adding control signals.
All control signals should have a high voltage from Vcc – 1.
Analog to Digital Converter – ADC/ADC
The following control signals are used to control the conversion. The maximum frequence of the clock is 1. A, B, and C. Modification to the source code datashheet required to use more than just four channels. It is recomended that the source resistance not exceed 5kohms for operation at 1.
The signal goes low once a conversion is initiated by the start signal and remains low until a conversion is complete. It is the MSB of the select lines. Dataeheet means that in order to get it to work, there is a total of seven control signals that must be sent from the FPGA. In this implementation the OE signal is pulsed high one clock cycle after the EOC signal goes high and remains high until the data addc0809 safely stored into the desired register in the FPGA.
It is the Second bit of the select lines. On the rising edge of the pulse the internal registers are cleared and on the falling edge of the pulse the conversion is initiated. It can be tied to the Start line if the clock is operated under kHz.
Be sure to consult the ratasheet data-sheets for other chips. This is an address select line for the multiplexer.
This means that an entire conversion takes at least 64 clock cycles. This means it must remain stable for up to 72 clock cycles. The source must remain stable while it is being sampled and should contain little noise.
At clock speeds greater datasneet that the user must make certain that enough time has passed since the ALE signal was pulsed so that the correct address is loaded into the multiplexer before a conversion begins. Like the ALE pulse the minimum pulse width is ns.
You will also need to download multiplex. Users can look for a rising edge transition. See table 1 for details. This is a bit of the digital converted output.
Table 2 provides a summary of all of the input axc0809 output to the chip. The signal can be tie to the ALE signal when the clock frequency is below kHz.
The ALE should be pulsed for at least ns in order for the addresses to get loaded properly. There are a couple of limitations that follow: Control signal from FPGA. If Datqsheet and ground are used as reference voltages, they should be isolated by decoupling with a 1 microF capacitor.