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Description |
Diamond-MM has a full set of features to support a wide range of analog and digital I/O application requirements. The analog input circuit uses a 12-bit A/D converter and can be configured for single-ended or differential input wiring, as well as unipolar or bipolar input ranges. It also offers 10 different input ranges, so it can work with a wide variety of input signals. The maximum A/D conversion rate is approximately 2,000-20,000 per second using interrupts (depending on the operating system).
Two analog outputs provide 12-bit resolution over a 0-5V or user-adjustable output range with 8mA drive current and 4uS settling time. The D/A can also be used as a digital attenuator for an analog signal fed into one of the reference inputs.
The board contains 8 digital inputs and 8 digital outputs. It has an on-board 82C54 counter/timer chip to control the A/D sampling rate and provide general purpose counting functions.
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Analog Input Ranges |
Diamond-MM supports multiple analog input voltage ranges, including both unipolar (+ only) and bipolar (+ and) ranges. In addition, a gain amplifier circuit allows you to reduce the input range to handle smaller signals.
To get the best resolution, select the smallest input range that is large enough to cover the entire range of your input signals. You can also install a resistor to customize the range exactly to your requirements. Note: On any A/D converter, the input range is the same as the full-scale A/D range divided by the gain. On Diamond-MM, the full-scale A/D range is 0-5V in unipolar mode and ±5V in bipolar mode.
Unipolar
| Input Range |
Resolution |
| 0 - 10V |
2.44mV |
| 0 - 5V |
1.22mV |
| 0 - 2.5V |
0.61mV |
| 0 - 1V |
0.244mV |
| 0 - 0.5V |
0.122mV |
| Custom |
(10KΩ /R)/4096)V |
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Bipolar
| Input Range |
Resolution |
| >±10V |
4.88mV |
| ±5V |
2.44mV |
| ±2.5V |
1.22mV |
| >±1V |
.488mV |
| ±0.5 |
.244mV |
| Custom |
(10KΩ /R)/2048)V |
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Analog Output Ranges |
The full-scale analog output voltage range is unipolar and is preset to 0 - 5V. However, you can adjust this range anywhere from 0 - 4V to 0 - 10V by adjusting a potentiometer on the board. You can also supply an external reference signal to each DAC individually to select unique ranges for each output channel. If the reference signal is an AC waveform (e.g. an audio signal), then the DAC can be used as an attenuator (volume control).
Note: The -NA versions of Diamond-MM do not have analog outputs.
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A/D Conversion Methods and Rates |
To provide flexibility in integrating with your application, Diamond-MM offers several methods of controlling A/D conversions. An A/D conversion can be triggered in 3 different ways: software command, external trigger, or on-board pacer clock. After the conversion is done, the data can be transferred from the board to system memory in 3 ways: software command, interrupt routine, or DMA transfer. Different conversion rates require the use of different transfer ethods:
| Software command |
2,000/sec max (approx.) |
| Interrupt routine |
20,000/sec max (approx.) |
| DMA transfer |
100,000/sec max (board limit) |
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Free Software |
Diamond-MM comes with free driver software compatible with C and Basic anguages. Example programs are included to get you started quickly. Some examples of the supported board operations are:
- A/D conversion on single channel
- A/D conversion scan on multiple channels
- Interrupt-based A/D conversions
- DMA A/D conversions
- Analog output on single channel
- Analog output on both channels
- Program counter/timers
- Digital input, bit and byte
- Digital output, bit and byte
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I/O Header Pinout |
| Vin 15 / 7- |
1 |
2 |
Vin 7 / 7+ |
| Vin 14 / 6- |
3 |
4 |
Vin 6 / 6+ |
| Vin 13 / 5- |
5 |
6 |
Vin 5 / 5+ |
| Vin 12 / 4- |
7 |
8 |
Vin 4 / 4+ |
| Vin 11 / 3- |
9 |
10 |
Vin 3 / 3+ |
| Vin 10 / 2- |
11 |
12 |
Vin 2 / 2+ |
| Vin 9 / 1- |
13 |
14 |
Vin 1 / 1+ |
| Vin 8 / 0- |
15 |
16 |
Vin 0 / 0+ |
| Analog Ground |
17 |
18 |
VRef Out (+5V/-5V) |
| Analog Ground |
19 |
20 |
Vout 0 |
| Analog Ground |
21 |
22 |
Vout 1 |
| Analog Ground |
23 |
24 |
+15V Output |
| -15V Output |
25 |
26 |
VRef In 0 |
| Analog Ground |
27 |
28 |
VRef In 1 |
| Counter 0 in- |
29 |
30 |
Digital Ground |
| Counter 0 Out |
31 |
32 |
Counter 2 Out |
| Digital Out 7 |
33 |
34 |
Digital Out 6 |
| Digital Out 5 |
35 |
36 |
Digital Out 4 |
| Digital Out 3 |
37 |
38 |
Digital Out 2 |
| Digital Out 1 |
39 |
40 |
Digital Out 0 |
| Digital In 7 |
41 |
42 |
Digital In 6 |
| Digital In 5 |
43 |
44 |
Digital In 4 |
| Digital In 3 |
45 |
46 |
Digital In 2 |
| Digital In 1 |
47 |
48 |
Digital In 0 |
| +5V |
49 |
50 |
Digital Ground |
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Specifications |
| Analog Inputs |
| Number of inputs |
8 differential or 16 single-ended (user selectable) |
| A/D resolution |
12 bits (1/4096 of full scale) |
| Bipolar ranges |
±10V, ±5V, ±2.5V, ±1V, ±0.5V, Custom |
| Unipolar ranges |
0-10V, 0-5V, 0-2.5V, 0-1V, 0-.5V, Custom |
| Input bias current |
50nA max |
| Max. input voltage |
±10V for linear operation |
| Overvoltage protection |
±35V on any analog input |
| Input Impedance |
10^13 ohms |
| Conversion trigger |
software trigger, internal pacer clock, or external TTL signal |
| Analog Outputs |
| Number of outputs |
2 |
| D/A resolution |
12 bits (1/4096 of full scale) |
| Output ranges |
0-5V, adjustable, or external reference input |
| Output current |
±8mA max per channel |
| Settling time |
4µS max to ±2/2 LSB |
| Relative accuracy |
±1 LSB |
| Nonlinearity |
±1 LSB, monotonic |
| Reset |
All channels reset to OV |
| Digital I/O |
| Number of inputs |
8, HCT/TTL compatible |
| Input voltage |
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| Logic 0: |
0.0V min, 0.85 max |
| Logic 1: |
2.0V min, 5.0V max |
| Input current |
±1µA max |
| Number of outputs |
8, HCT/TTL compatible |
| Output voltage |
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| Logic 0: |
0.0V min, 0.33 max |
| Logic 1: |
3.8V min, 5.0 max |
| Output current |
±4mA max per line |
| Counter/Timers |
| A/D Pacer clock |
32-bit down counter (2 82C54 counters cascaded) |
| Clock source |
10MHz on-board source or external signal |
| General purpose |
16-bit down counter (1 82C54 counter) |
| Interrupt/DMA trigger |
End of A/D conversion |
| General |
| Power supply |
+5VD±10%@165mA typical |
| ±15V output current |
±10mA max with DACs unloaded |
| Operating temperature |
0°C to +70°C Standard, -40°C to +85°C Extended |
| Weight |
3.3oz/93g |
| MTBF |
DMM-XT 372,809 hours |
| RoHS |
Compliant |
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