Campbell Scientific SDM-IO16 16-Channel Input/Output Expansion Module - Manual (Page 9)

SDM-IO16 16 Channel Input/Output Expansion Module
Mounting: Mounting brackets have two holes at 225 mm
nominal spacing. Mounting screws and plastic
inserts suitable for use with Campbell
Scientific enclosures are also supplied.
Weight: 350 g (including brackets)
EMC status: Complies with EN61326:1997
Total SDM cable length: 6 m maximum recommended
2.2 Port Specifications (Output Mode)
Output voltage (no load): Output ON/HI, Nominal 5 V (Minimum 4.5 V)
Output OFF/LO, Nominal 0 V (Maximum 0.1 V)
Output sink current: Output will sink 8.6 mA from a 5 V source 1
Output source current: Output will source 42 mA @ 3 V, 133 mA
short-circuited to ground
1
Max. output current: Limited by the 12 V supply.
(total for all outputs)
2.3 Port Specifications (Input Mode)
Input voltage: Input high, 4.0 V minimum threshold
Input low, 1.0 V maximum threshold
All inputs feature Schmitt triggered detectors.
Input protection: The input is clamped at -0.6 V and +5.6 V
relative to ground via a 33
Ω resistor 1 . This will
withstand a continuous current flow of 200 mA
(including that which might be caused by
accidentally connecting directly to a 12 V
supply). To limit power dissipation and
damage at higher voltages than 12 V, an
external series current limiting resistor is
recommended.
Input impedance: The input is biased to +5 V relative to ground
by a 100 kohm resistor.
2.4 Pulse Counting Specifications
Maximum frequency: 2.048 KHz on all channels simultaneously with
switch debounce-mode set off, with a 50/50
duty cycle.
150 Hz on all channels with default switch
debounce timing enabled and a 50/50 duty
cycle
2 .
3