OM-USB-1208HS Series User's Guide
Specifications
20
Counters
Table 9. Counter specifications
Parameter
Specification
Counter terminal names
CTR0, CTR1
Counter type
Event counter
Number of channels
2
Input type
Schmitt trigger, 33 Ω series resistor, 47 kΩ pull-down to ground
Schmitt trigger hysteresis
0.4 V to 1.2 V
Input high voltage
2.2 V min
5.5 V absolute max
Input low voltage
1.5 V max
–0.5 V absolute min
0 V recommended min
Resolution
32 bits
Maximum input frequency
20 MHz
Counter read/write rates
(software paced)
33 to 8000 reads/writes per second typ, system dependent
High pulse width
25 ns min
Low pulse width
25 ns min
Timer
Table 10. Timer specifications
Parameter
Specification
Timer terminal name
TMR
Timer type
PWM output with count, period, delay, and pulse width registers
Output value
Default state is idle low with pulses high, software-selectable output invert
Internal clock frequency
40 MHz
Register widths
32 bits
High pulse width
20 ns min
Low pulse width
20 ns min
Output high voltage
4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –24 mA)
Output low voltage
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 24 mA)
Output current
±24 mA max per pin (see "Power" section for additional information)
Memory
Table 11. Memory specifications
Parameter
Specification
Data FIFO
OM-USB-1208HS:
4 kS analog input
OM-USB-1208HS-2AO:
4 kS analog input/4 kS analog output
OM-USB-1208HS-4AO: 4 kS analog input/4 kS analog output
Non-volatile memory
32 KB (16 KB firmware storage, 16 KB calibration/user data)
