Noggin
Member
For my senior design project, we are making a device to go into a vehicle. Our instructor is pushing us to test this device against SAE standards. One of tests I'm working on is electrical noise. I need to generate 0.15, 0.5, 1, and 4v signals peak to peak and place them on all input pins of the device.
The SAE standards also call for a capacitor of a minimum 100 uF to be placed at the output leads.
The schematic below is what I came up with in PSPICE to use as a circuit, I purchased a 120v@760mA to 25v@2A transformer from Radio Shack to use as the transformer. I'm hoping it will be beefy enough to handle the current.
Everything looked great until I added in the DC resistances of the inductors.... the output at 1 kHz went from a 4v swing centered at 12v, to just under a 1v swing centered on 9.7v. The 9.7v I can live with, but is anyone familiar enough with SAE standards to shed some light on this? Is it ok for the Pk - Pk voltage to drop as frequency increases? With a 10kHz input freq, the swing drops to .1v.
By the way, the V1 sin generator will have an offset voltage to keep it from dipping below 0v. And I can turn up the amplitude, but only so much. And I don't know what the actual coupling is, so I just set it to 1, but I realize that its not.
The SAE standards also call for a capacitor of a minimum 100 uF to be placed at the output leads.
The schematic below is what I came up with in PSPICE to use as a circuit, I purchased a 120v@760mA to 25v@2A transformer from Radio Shack to use as the transformer. I'm hoping it will be beefy enough to handle the current.
Everything looked great until I added in the DC resistances of the inductors.... the output at 1 kHz went from a 4v swing centered at 12v, to just under a 1v swing centered on 9.7v. The 9.7v I can live with, but is anyone familiar enough with SAE standards to shed some light on this? Is it ok for the Pk - Pk voltage to drop as frequency increases? With a 10kHz input freq, the swing drops to .1v.
By the way, the V1 sin generator will have an offset voltage to keep it from dipping below 0v. And I can turn up the amplitude, but only so much. And I don't know what the actual coupling is, so I just set it to 1, but I realize that its not.