Model 526 measures incremental encoders pulses, analog voltages and detects digital signals. It also generates analog voltages, digital outputs and has a watchdog timer and an interrupt timer.
Encoder Counters
The four quadrature encoder inputs and index inputs may be differential (RS-422) or single-ended TTL. Counting resolution can be increased by selecting x2 or x4 counting modes. Each counter may be programmed to cause an interrupt when it overflows. The current value of a counter may be read without affecting the counting process.
Counters may be configured as timers by counting pulses from an internal clock of 27 or 13.5 MHz. Timers can generate a single-shot pulse or a pulse width modulated waveform at one of the digital outputs.
Watchdog Timer
If enabled, the watchdog timer times out after a selected interval if it is not tagged. This timer can control two external solid state relays (one normally closed and one normally open).
Interrupt Timer
This timer provides a way of generating precise interrupts. Two operating modes are available: manual and auto-restart. In the manual restart mode the count starts on a software command and stops when the zero count is reached. In Auto-restart mode the counter automatically reloads after the zero count is reached.
Analog Outputs
The 526 has four 16-bit D/A converters with individual preload buffers. A single command will update all D/A’s in about 32 uS. An interrupt can optionally be generated when the upload is complete. There are no trimpots for the 526’s D/A’s. Sensoray’s factory calibration stores calibration data in an EEPROM on the 526. Precise output voltages are obtained by using this data.
Analog Inputs
The eight differential inputs are multiplexed to a 16-bit A/D. The input range is slightly larger than ±10 volts to allow for software calibration. Multiple channels can be measured with just one command. Two reference channels (0 V and 10 V) can also be measured.
The A/D converter is factory calibrated by storing the actual value of the on-board 10 V reference in the EEPROM.
Digital I/O
The 526 has eight I/O lines for use as general purpose inputs or outputs in groups of four. Interrupts can be generated on the rising or falling edge of every signal in both groups.
DC/DC Converter
The 526 requires a power supply input of just 5 volts. Its on-board DC/DC converter generates +/- 15 volts for the analog circuits and 3.3 volts for the digital circuits.
Specifications
| Power input |
5 volts, 280 mA |
| I/O ports |
27 ports |
| A/D range |
±10 volts |
| A/D resolution |
305 uV |
| A/D throughput |
10 kHz one channel |
| A/D noise |
2 sigma = 4 counts |
| A/D format |
2’s complement |
| D/A range |
± 10 volts |
| D/A resolution |
305 uV |
| D/A throughput |
10 kHz |
| D/A driver noise |
2 sigma = 4 counts |
| D/A driver current |
± 5 mA |
| Encoder signals |
RS-422 clockA, clockB, index,5 V |
| Counter type |
Four 24-bit synchronous up/down with preload, interrupts |
| Encoder count rate |
10 MHz at 1x, 5 MHz at 2x, 2.5 MHz at 4x |
| Digital I/O |
8 lines with outputs connected to inputs |
| Output drive current |
25 mA |
| Output sink current |
25 mA |
| Input pullup resistor |
10 k ohm |
| Edge detection |
State change 0 to 1, 1 to 0 |
| Watchdog timer |
0.125 to 16 seconds |
| Interrupt timer interval |
100 us to 25.5 ms |
Images and Mechanical Drawings
Prices
| Model 526 |
Multi I/O module with A/D |
Qty. 1 $563 |
Qty. 2-9 $512 |
| Model 301-6 |
PC/104+ CPU |
Qty. 1 $297 |
Qty. 2-9 $280 |
| Model 207 |
PC/104 Isolated power supply |
Qty. 1 $113 |
Qty. 2-9 $119 |
| Model 7409C |
Analog I/O 18” flat cable |
Qty. 1 $19 |
Qty. 2-9 $18 |
| Model 7409C1 |
Analog I/O 1 meter flat cable |
Qty. 1 $28 |
Qty. 2-9 $25 |
| Model 7506TDIN |
40 contact terminal board |
Qty. 1 $79 |
Qty. 2-9 $72 |
| Model 7501C |
Digital I/O 18” flat cable |
Qty. 1 $17 |
Qty. 2-9 $15 |
| Model 7501C1 |
Digital I/O 1 meter flat cable |
Qty. 1 $30 |
Qty. 2-9 $27 |
| Model 7505TDIN |
50 contact terminal board |
Qty. 1 $79 |
Qty. 2-9 $72 |
