CHEETAH Hardware User’s Manual
Imperx, Inc.
Rev 1.7
6421 Congress Ave.
8/26/2016
Boca Raton, FL 33487
+1 (561) 989-0006
47 of 121
A.
Input IN 1- Opto-Isolated
The input signal “IN 1” and “IN 1 Rtn” are optically isolated and the voltage
difference between the two must be positive between 3.3 and 5.0 volts. To limit the
input current, a 160 Ohm internal resistor is used, but the total maximum current
MUST NOT
exceed 5 mA.
Figure 21
: IN1 electrical connection
B. Input IN 2 LVTTL
The input signals “IN 2” and “IN 2 Rtn” are used to interface to a TTL or LVTTL
input signal. The signal level (voltage difference between the inputs “IN 2” and “IN
2 Rtn”)
MUST
be LVTTL (3.3 volts) or TTL (5.0 volts). The total maximum input
current
MUST NOT
exceed 2.0 mA.
Figure 22:
IN 2 electrical connection