WinLTP
Version 2.20b
Leading-Edge Features
Special Features
Ordinary Features
Additional Features

Internal Gain on M- and X-Series Boards

Using the Internal Gain on M- and X-Series National Instruments Boards

In WinLTP 2.10 we have implemented the internal gain that is present in M- and X-series National Instruments boards.  The internal gains can be x1, x2, x10 and x50 for the inexpensive boards like the PCIe-6321, or x1, x2, x5, x10, x20, x50 and x100 for the more expensive boards like the PCIe-6353.

For voltage amplifiers with only x10 external gain (like the Axon AxoClamp-2B), this allows the data acquisition board to supply the necessary additional gain rather than having to put in a second external amplifier (Fig. 4B).

 
Fig. 4. External and internal gain arrangements.  A) Gain arrangement prior to WinLTP 2.10 has only the ‘Gain’ is the total gain and is equal to the external gain, with the NI board internal gain equal to x1. So if you have an external preamp with a x10 gain like the AxoCalmp-2B, you have to add an external second amplifier (here at x50) to bring the total gain (eg ‘Gain’) in this example to to x500.  B) In WinLTP 2.10 internal gain was added.  So if you have an external preamp with a x10 gain like the AxoCalmp-2B, you do not need to have an external second amplifier.  Therefore setting the ‘External Gain’ to x10 and the NI board ‘Internal Gain’ to x50 brings the ‘Total Gain’ to x500.