Measurement Computing USB-2416-4AO - Manual (Page 39)

USB-2416-4AO User's Guide Specifications
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Note 5: The external pull-up is connected to the digital output bit through an external pull-up resistor. Adding an
external pull-up resistor connects it in parallel with the internal 47
kΩ pull-up resistor of that particular
digital input/output bit. Careful consideration should be made when considering the external pull-up
resistor value and the resultant pull-up voltage produced at the load.
Note 6: Does not include the additional leakage current contribution that may occur when using an external pull-up
resistor.
Counter
Table 27. CTR specifications
Parameter Conditions Specification
Pin name CTR0, CTR1
Number of channels 2 channels
Resolution 32-bits
Counter type Event counter
Input type Schmitt trigger, rising edge triggered
Input source CTR0 (pin 43)
CTR1 (pin 45)
Counter read/writes rates
(software paced) Counter read System dependent, 500 reads per second.
Counter write System dependent, 500 writes per second.
Input characteristics Each CTRx input pin 562 K
Ω pull-up resistor to +5 V, 10 kΩ series
resistor
Input voltage range ±15 V maximum
Maximum input voltage range CTR0,CTR1 relative to GND and
DGND (pins
18,36,39,42,44,46,66,81,84,93,94) ±20 V maximum (power on/off)
Input high voltage 1.3 V minimum, 2.2 V maximum
Input low voltage 1.5 V maximum, 0.6 V minimum
Schmitt trigger hysteresis 0.4 V minimum, 1.2 V maximum
Input bandwidth (-3 dB) 1 MHz
Input capacitance 25 pf
Input leakage current ±120 nA
Input frequency 1 MHz, maximum
High pulse width 500 ns, minimum
Low pulse width 500 ns, minimum
Note 7: The DGND and GND pins (pins 18,36,39,42,44,46,66,81,84,93,94) are common and are isolated from
earth ground.
Memory
Table 28. Memory specifications
EEPROM 4096 bytes isolated micro reserved for sensor configuration
256 bytes USB micro for external application use
Microcontroller
Table 29. Microcontroller specifications
Type One high-performance 8-bit RISC microcontroller with USB interface (non-isolated)
One high-performance 16-bit RISC microcontroller for measurements (isolated)