101-0566 Rabbit Semiconductor, 101-0566 Datasheet - Page 37

• Manufacturer Part Number: 101-0566
• Description: COMPUTER SNGLBD BL2100 FRCTNLOCK
• Manufacturer: Rabbit Semiconductor

Specifications of 101-0566

• Module/board Type: Single Board Computer Module
• For Use With/related Products: BL2100
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

3.7 Analog Reference Voltage Circuit
Figure 21 shows the analog voltage reference circuit.
This circuit generates the 4.096 V reference voltage, which is used by the A/D converter
and by the D/A converters. This sets the operating range of the A/D converter and the D/A
converters (0–10 V). To use the full accuracy of the A/D converter and the D/A convert-
ers, this voltage must be accurate to the same degree.
The reference zener diode in combination with the 300  resistor form a shunt regulator.
The 4.096 V reference voltage then feeds the A/D converter, the D/A converters, and the
voltage divider composed of the 10 k and the 14 k resistors. The voltage divider gener-
ates a second reference voltage of 1.707 V to feed the four op-amps for the buffered A/D
converter inputs.
The 2.048 V reference voltage is also used to generate the 2.5 V reference for D-REF used
in the digital output circuit.
User’s Manual
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Figure 21. Analog Reference Voltages
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