The Sensoray Model 421 low cost interface saves
space in ISA bus systems by combining five functions into one module.
Four flat cables connect the Model 421 to external breakout boards.
Encoders
Three 16-bit up/down counter channels are optimized for incremental encoders. Each channel accepts two phased TTL or RS-422 signals to track encoder direction and displacement. Unlike conventional counters, the 421 counters do not accumulate errors when the encoder dithers or changes direction. The 421 supplies 5-volt power to each encoder channel.
A/D
Eight differential input channels are multiplexed to a sample/hold and successive approximation A/D. A resistor-programmable instrumentation amplifier allows gains of 1 to 1000. The 15-volt outputs from the DC/DC supply ensure A/D linearity for 10 volt input signals.
D/A
Four voltage outputs channels may be programmed for 0 to +10 volts. One channel has a remote sense input to minimize line loss errors. All output voltages are reset to zero volts whenever a bus reset occurs.
Watchdog
The 421's watchdog timer output may be routed to either bus reset or nonmaskable interrupt. It may be enabled or disabled under program control. The timer is automatically disabled whenever a bus reset occurs.
Digital I/O
The Model 421 has forty-eight digital I/O lines with industry standard pinouts for solid state relay boards. Each line is software programmable as an input or output. The status of output lines may be monitored by software. Whenever a system reset occurs all output channels are turned off.
Specifications
| Operating temperature |
-25C to +70C |
| PC bus interface |
I/O mapped, 16 ports |
| Input power |
< 3 watts |
| A/D Converter |
| Conversion time |
20 uS |
| Number of channels |
8 differential |
| Input resistance |
100 Megohms |
| CMRR |
100 dB minimum |
| Max. common mode voltage |
5 volts |
| Resolution |
12-bits |
| Accuracy |
14-bits |
| Input ranges |
+/-10, ±5 V |
| Offset error |
+/- 1/2 LSB |
| D/A converter |
| Conversion time |
200 uS |
| Resolution |
12-bits |
| Offset error |
+/- 2 LSB |
| Output voltage |
+/- 10 volts |
| Output resistance |
87 ohms |
| Digital I/O |
|
| Number of channels |
48 bi-directional |
| Output voltage |
0 to 5 V open collector |
| Output sink current |
100 mA @1.1 V |
| Encoder I/O |
|
| Number of channels |
3 quadrature, 16-bit |
| Input voltage |
TTL or RS-422 |
| Input frequency |
350 kHz |
| Watchdog Timer Time-out |
Time-out: 500 mS
2-pin connector may be connected to the bus reset line to allow a system reset from software |
Images and Mechanical Drawings
Prices
| Model 421 |
Analog & Digital Interface |
Qty:1 $303 |
Qty:2-9 $275 |
| Model 7409C |
18" analog cable, 40-pin |
Qty:1 $14 |
Qty:2-9 $12 |
| Model 7409C1 |
1 meter analog cable, 40-pin |
Qty:1 $28 |
Qty:2-9 $25 |
| Model 7409TB |
Low cost analog screw terminal board |
Qty:1 $65 |
Qty:2-9 $59 |
| Model 7409TC |
Screw terminal board with proto area |
Qty:1 $105 |
Qty:2-9 $95 |
| Model 7409TDIN |
Screw terminal board with proto area and DIN snap rails |
Qty:1 $140 |
Qty:2-9 $125 |
| Model 7501C |
18" digital cable, 50-pin |
Qty:1 $17 |
Qty:2-9 $15 |
| Model 7501C1 |
1 meter digital cable, 50-pin |
Qty:1 $30 |
Qty:2-9 $27 |
| Model 720RB |
24 position relay board w/o DIN |
Qty:1 $145 |
Qty:2-9 $130 |
| Model 7505TDIN |
24 position relay board
with DIN snap rails |
Qty. 1 $79 |
Qty. 2-9 $72 |
| Model 720RB |
Solid State Relay Board |
Qty. 1 $145 |
Qty. 2-9 $130 |
| Model 720RBDIN |
Solid State Relay Board |
Qty. 1 $180 |
Qty. 2-9 $165 |
| Model 7502C |
18" encoder cable, 20-pin |
Qty. 1 $12 |
Qty. 2-9 $11 |
| Model 7502C1 |
1 meter encoder cable, 20-pin |
Qty. 1 $25 |
Qty. 2-9 $23 |
| Model 7506TDIN |
40 contact terminal board |
Qty. 1 $79 |
Qty. 2-9 $72 |
| Model 7505TDIN |
50 contact terminal board |
Qty. 1 $79 |
Qty. 2-9 $72 |
| Model 7502TDIN |
Screw terminal board with DIN snap rails |
Qty. 1 $49 |
Qty. 2-9 $49 |
