Hi All,
I've been trying to use a Dataq DI-154RS to do some datalogging. With very little success. The device has four input channels for A to D conversion. Even with the inputs shorted, there is several bits of noise. Working with a signal is even worse. Using a very quiet voltage source, it still sees over 100 millivolts of noise. Monitoring the same signal with a meter shows no noise down to the millivolt level.
The active device inside is a PIC 16C770. With no input, each line in shows 3.3 volts. My meter sees the 3.3 volts at the input terminals. This falls to .33 volts when the device is not active, but powered up.
I have not been able to get the datasheet to load down from Microchip. Does anybody have any experience with this device? Is this one broken, or are they really this horrible? I just can't imagine a piece of test equipment that injects a voltage artifact into the input.
I've been trying to use a Dataq DI-154RS to do some datalogging. With very little success. The device has four input channels for A to D conversion. Even with the inputs shorted, there is several bits of noise. Working with a signal is even worse. Using a very quiet voltage source, it still sees over 100 millivolts of noise. Monitoring the same signal with a meter shows no noise down to the millivolt level.
The active device inside is a PIC 16C770. With no input, each line in shows 3.3 volts. My meter sees the 3.3 volts at the input terminals. This falls to .33 volts when the device is not active, but powered up.
I have not been able to get the datasheet to load down from Microchip. Does anybody have any experience with this device? Is this one broken, or are they really this horrible? I just can't imagine a piece of test equipment that injects a voltage artifact into the input.