Measurement Computing PCM-QUAD02 - Manual (Page 14)

Chapter 4
Specifications
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Power consumption
Table 1. Power consumption specifications
Parameter Specification
Not supplying power to external encoders:
+5V
80 mA max, 50 mA typical
Typical supplying one Dynamics Research Incremental Optical Rotary Encoder — part number M21AAFOBB2E-2500
+5V 179
mA
Maximum peak current to encoders
(each) 400 mA
Input
Table 2. Input specifications
Receiver type SN75ALS175 quad differential receiver
Configuration Each channel consists of Phase A input, Phase B input and Index input; each is
configured for differential input
Number of channels 2
Common mode input voltage range ±12 V max
Differential input voltage range ±12 V max
Input sensitivity ±200 mV
Input hysteresis 50 mV typ
Input impedance 12 KΩ min
Propagation delay 27 ns max
Absolute maximum input voltage Differential: ±25 V max
Miscellaneous ƒ Meets EIA RS422, 423, 485 and CCITT V.10, V.11, X.26, X.27.
ƒ Designed for multipoint buses on long lines in noisy environments.
Counter
Table 3. Counter specifications
Counter type LS7266R1 24-bit Dual-axis Quadrature Counter
Quadrature Mode Clock frequency: 4.3 MHz max
Separation: 57 ns min
Clock pulse width: 115 ns min
Index pulse width: 85 ns min
Count Mode Clock frequency: 30 MHz max, (25 MHz max Mod-N mode)
Clock A - high pulse width: 16 ns min
Clock A - low pulse width: 16 ns min
Filter clock (FCK) 10 MHz
Digital filter rate 10 MHz, software selectable divider (1 to 256 in single steps)
Crystal oscillator (FCK source) Frequency: 10 MHz
Frequency accuracy: 100 ppm
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