The GX1164 provides 8 channels with 8-steps of binary programmable resistors. The 8 channels are divided into 2 groups of 4 channels each (channel 1 through 4 for the first group and channel 5 through 8 as the second group).
The following explanation refers to the Gx1164, all the other modes (Gx1164-2, Gx1164-4, Gx1164-8 and GX1164-0.25) have the same architecture but with different resistors values.
the figure below illustrates the configuration of a single group. Channels 1 and 3 resistors’ (CHx and CHx+2) have binary ladder values from 1W to 128W and can therefore simulate resistors from 1W to 255W. Channels 2 and 4 resistors’ (CHx+1 and CHx+3) have binary ladder values from 256W to 32KW and can therefore simulate resistors from 256W to 64KW.
Three relays connect channels within groups to allow wider resistance ranges and the use of a group as a potentiometer with a wiper. There are also bypass relays to increase accuracy when selecting low resistance values.
GX1164 Typical Group
The GX1164 resistance range of each group is as follows:
Single channel mode:
Four programmable resistor channels of 1W to 255W (this range applies to channels 1,3, 5 and 7)
Four programmable resistor channels of 256W to 65,535W (this range applies to channels 2, 4, 6 and 8)
Each group may also be used as double channel mode providing four programmable resistor channels of 1W to 65,535W (by combining channels 1 through 8 as shown in the figure above)
Or in Wiper Mode, where each group can emulate a variable resistor (potentiometer):
One programmable resistor channel of 1W to 128KW (by combining channels 1, 2, 3 and 4 as shown in the figure above) with ‘wiper’ connection between channels 2 and 3.
One programmable resistor channel of 1W to 720KW (by combining channels 5, 6, 7 and 8 as shown in the figure above) with ‘wiper’ connection between channels 6 and 7.
By selecting which resistor will be used (corresponding relay open) or shorted (relay closed), the GX1164 can provide any resistance value in the programmable range with resolution equal to the module’s resistance ladder value – 0.25, 1, 2 , 4, or 8 ohms.