Rabbit Smartcat, User Manual

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30 Smartcat (BL2100)
3.6 D/A Converter Outputs
Only the BL2100 and the BL2120 models are stuffed with D/A converters. The D/A con-
verter outputs are buffered and scaled to provide an output from 0 V to +10 V.
NOTE: The D/A converter output voltage depends on the original power-supply voltage,
+RAW, so if +RAW < 13 V, the maximum D/A converter output will be +RAW – 3 V.
Figure 19 shows the D/A converter outputs.
Figure 19. D/A Converter Outputs
To stay within the maximum power dissipation of the D/A converter circuit, the maximum
D/A converter output current is 10 mA per channel for a power-supply voltage, +RAW, up
to 15 V, and drops to 2 mA per channel for a power-supply voltage of 36 V.
Figure 20. Maximum D/A Converter Output
Current vs. Power-Supply Voltage
The D/A converter inputs are factory-calibrated and the calibration constants are stored in
flash memory. You may calibrate the A/D converter inputs at a later time using the software
functions described in Section 4.4.5, “D/A Converter Outputs.” The
GETCALIB.C
and
the
SAVECALIB.C
sample programs in the Dynamic C
SAMPLES\BL2100\
Calib_Save_Retrieve
folder illustrate how to retrieve and save calibration data.
100 nF
255 k W
DAC
102 k W
DAC00
AGND
ADREF
86.6 k W
DAC01
D/A
Converter Output Current (mA)
Power-Supply Voltage, +RAW (V)
10
2
9
15 36