Specifications; Ttl Inputs And Outputs - National Instruments NI PCIe-8255R Getting Started

Specifications

The following specifications apply to the NI 8255R image acquisition device. These specifications are
typical at 25 °C, unless otherwise stated.

TTL Inputs and Outputs

Digital logic levels
Input low voltage (V
Input high voltage (V
Output low voltage (V
Output high voltage (V
TTL Inputs
Number of channels ...............................................2
Maximum pulse rate ..............................................2 MHz
Minimum pulse detected........................................500 ns
Power-on state........................................................Input (high-impedance) 61.9 kΩ pull-up to 5 V
TTL Outputs
Number of channels ...............................................10
Output voltage range..............................................0 V to 5 V
Maximum pulse rate ..............................................2 MHz
Optically Isolated Inputs and Outputs
Isolated (Current Sinking) Inputs
Number of channels ...............................................13
Input voltage range ................................................0 V to 30 V
Input ON voltage............................................3.5 V to 30 V
Input OFF voltage ..........................................0 V to 2 V
Turn-on current ..............................................7.1 mA, typical
Maximum pulse rate ..............................................100 kHz
Minimum pulse detected........................................10 μs
Reverse polarity protection ....................................Yes, –30 V
Isolated (Current Sourcing) Outputs
Number of channels ...............................................4
On-state voltage range ...........................................5 V to 30 V, maximum
Maximum on-state voltage
drop from V ...................................................1.2 V at 100 mA
© National Instruments Corporation
Level
)
IL
)
IH
), at 5 mA
OL
), at 5 mA
OH
9
Minimum
0 V
2.2 V
—
2.4 V
14 mA, maximum
Getting Started with the NI PCIe-8255R
Maximum
0.5 V
5 V
0.4 V
—