
2.4 Input Control
2.4.1 Input Supply
The USBcount50 supports a programmable input supply via the slider control.
Supplies from 1.50V to 5.00V are possible, and the slider control adjusts in 256 steps of 13.67mV per step. This range allows the user to match against common industry standard logic levels present in their circuit to be measured6.
6Note that the input switching threshold is not a linear function of the supply voltage, rather the threshold varies in steps as the supply voltage is increased, corresponding to the Vih specifications for 1.8V, 2.5V, 3.0V, 3.3V and 5.0V logic domains.
Elan Digital Systems Ltd. | 16 | USBcount50 USER’S GUIDE Iss1 |