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Input Voltage Calculations
The general formula for calculating the input voltage when the frequency and voltage range are known is:
Input Voltage = (Frequency(system clock + ZNoltage Range) - Otfset
The offset is 0 for unipolar voltage rangesand one-half the range for bipolar voltage ranges.
For 0 to +5 volts:
-0
lnput Voltage= (Frequency/100,000)
For 0 to +10 volts:
-0
lnput Voltage= (Frequency/50,000)
For -2.5 to +2.5 volts:
InputVoltage= (Frequency/l00,000)- 2.5
For -5 to +5 volts:
-5
InputVoltage= (Frequency/50,000)
Bit Calculations
The general formula for calculating the bit value when the frequency and resolution are known is:
Bit Value - (Frequency/(system
clock* 2/2N))- Offset
where N = the numberof bits of the desiredresolution.
and the offset is 0 for unipolaroperationand 0.5 x 2Nfor bipolaroperation.
For example,to calculatethe bit value for a l2-bit resolution:
Unipolar:
BitValue= (Frequency/(system
clock+ 2/4096))- 0
= Frequency/122.O7
Bipolar:
- 2048
Bit Value = (Frequency/(system
clock* 214096))
- 2048
= (Frequency/122.07)
For example,to calculate
thebit valuefor a l6-bit resolution:
Unipolar:
Bit Value = (Frequency/(system
clock+ 2/65,536))- 0
= FrequencyZ.629
Bipolar:
Bit Value = (Frequency/(system
clock+ 2/65,536))- 32,768
= (Frequencyfi.629) - 32,768
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