101-0522 Rabbit Semiconductor, 101-0522 Datasheet - Page 101

• Manufacturer Part Number: 101-0522
• Description: MODULE RABBITCORE RCM3220
• Manufacturer: Rabbit Semiconductor

Specifications of 101-0522

• Module/board Type: MPU Core Module
• For Use With/related Products: RCM3220
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 101-522; 101-522

Other possible ranges are possible by physically changing the resistor values that make up
the attenuator circuit.
It is also possible to read a negative voltage on ADC_IN0 to ADC_IN5 by moving the
jumper (see Figure B-5) on header JP7, JP6, or JP5 associated with the A/D converter
input from analog ground to VREF, the reference voltage generated and buffered by the
A/D converter. Adjacent input channels are paired so that moving a particular jumper
changes both of the paired channels. At the present time Rabbit does not offer the software
drivers to work with single-ended negative voltages, but the differential mode described
below may be used to measure negative voltages.
Differential measurements require two channels. As the name differential implies, the dif-
ference in voltage between the two adjacent channels is measured rather than the differ-
ence between the input and analog ground. Voltage measurements taken in differential
mode have a resolution of 12 bits, with the 12th bit indicating whether the difference is
positive or negative.
The A/D converter chip can only accept positive voltages. Both differential inputs must be
referenced to analog ground, and both inputs must be positive with respect to analog
ground. Table B-3 provides the differential voltage ranges for this setup.
RabbitCore RCM3700 User’s Manual
NOTE: THERM_IN7 was configured to illustrate the use of a thermistor with the sample
program, and so is not available for use as a differential input. There is also no resistor
attenuator for THERM_IN7, so its input voltage range is limited.
Min. Voltage
Table B-2. Positive A/D Converter Input Voltage Ranges
(V)
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Max. Voltage
+20.0
+10.0
+1.25
+5.0
+4.0
+2.5
+2.0
+1.0
(V)
Amplifier
Gain
10
16
20
1
2
4
5
8
mV per Count
0.625
0.500
1.25
2.5
2.0
1.0
10
5
99