Spectrum Brands MI.61XX manual Maximum Output Range, Output Filters, Filter Specifications

Analog Outputs Setting up the outputs

Maximum Output Range

In order not to generate distorted signals it is nec- essary to keep the total output range as a combina- tion of the set amplitude and offset within a range of ±3000 mV.

If this limit is exceeded a heavy distorted signal will be seen and the signals waveform will be cut off at the maximum range of +3000 mV or at the mini- mum range of -3000 mV.

To avoid heavily distorted output signals please make sure to keep the signals in a range of ±3000 mV.

To give you an example how the registers of the amplitude and the offset are to be used, the following example shows a setup to match all of the three signals shown in the offset figure.

SpcSetParam (hDrv, SPC_AMP0 ,	1000);	// Set up amplitude of channel0 to ± 1.0	V
SpcSetParam (hDrv, SPC_AMP1 ,	1000);	// Set up amplitude of channel1 to ± 1.0	V
SpcSetParam (hDrv, SPC_AMP2 ,	1500);	// Set up amplitude of channel2 to ± 1.5	V
SpcSetParam (hDrv, SPC_OFFS0,	0);	// Set the output offsets
SpcSetParam (hDrv, SPC_OFFS1,	500);
SpcSetParam (hDrv, SPC_OFFS2,	-500);

Output Filters

Every output of your Spectrum D/A board is equipped with a bypass path and three fixed filters that can be used for signal smoothing. The filters are located in the signal chain between the output amplifi- cation section and the DAC, as shown in the right figure. Depending on your type of board these filters are of differerent filter types and have different cut off frequencies, as shown below. As well as the set- ting for amplitude and offset, the settings for the filters can be changed at any time. The board will not be stopped for changing the different filters. You can choose between the different filters easily by setting the

dedicated filter registers. The registers and the possible values are shown in the table below.

Register		Value			Direction		Description
SPC_FILTER0		30080			r/w		Sets the signal filter of channel0.
SPC_FILTER1		30180			r/w		Sets the signal filter of channel1.
SPC_FILTER2		30280			r/w		Sets the signal filter of channel2.
SPC_FILTER3		30380			r/w		Sets the signal filter of channel3.
		0			No filter is used on the corresponding channel.
		1			Filter 1 is used on the corresponding channel. The type of filter depends on the type of board and is shown below.
		2			Filter 2 is used on the corresponding channel. The type of filter depends on the type of board and is shown below.
		3			Filter 3 is used on the corresponding channel. The type of filter depends on the type of board and is shown below.
Filter	Specifications		MI.6110			MI.6111
filter 0				No filter will be used.
filter 1	-3 dB bandwidth				25 MHz
filter 2	-3 dB bandwidth				5 MHz
filter 3	-3 dB bandwidth				500 kHz

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