ADC Primer


Address
Signal Name
Description
Conversion
ADC reading x
Typical Physics
Value
Typical Reading
ADC counts
ADC Span
Least Count
0
VOLTAGE_SUM
1.31mV/count-5.346V
 -5.1V
45
0-2.047V
2mV/count 1.4% 280ppm/°C
1
5V_POWER_SUPPLY
5mV/count
+4.93
987
0-5.115V 
5mV/count 1.4%  280ppm/°C
2
PRESSURE
See Note 1
~100kPa depending on weather
for unsealed DOM MB
852
0-5.115V 
5mV/count 2.5% 400ppm/°C
3
5V_CURRENT
2mA/count x
99.4mA
492
0-2.047V
2mV/count  1LSB 200ppm/°C
4
3.3V_CURRENT
0.2mA/count*(1/0.96)*(5V_POWER_SUPPLY/3.3V_POWER_SUPPLY)
300mA Note 4
97
0-2.047V
2mV/count  1LSB 200ppm/°C
5
2.5V_CURRENT
2mA/count*(1/0.90)*(5V_POWER_SUPPLY/2.5V_POWER_SUPPLY) 33.3mA Note 5
76
0-2.047V
2mV/count  1LSB 200ppm/°C
6
1.8V_CURRENT
0.2mA/count*(2/0.96)*(5V_POWER_SUPPLY/1.8V_POWER_SUPPLY) 685mA Note 6
120
0-2.047V
2mV/count  1LSB 200ppm/°C
7
MINUS_5V_CURRENT
2mA/count
250mA
125
0-2.047V
2mV/count  1LSB 200ppm/°C
8
DISC_ONE_SPE 0.01*(4mV/count-Pedestal)

605
0-4.092V
4mV/count 1.4% 280ppm/°C
9
1.8V_POWER_SUPPLY 2mV/count
1.74V
868
0-2.047V
2mV/count  1LSB 7ppm/°C
10 (0A)
2.5V_POWER_SUPPLY 4mV/count
2.50V
626
0-4.092V
4mV/count 1.4% 280ppm/°C
11 (0B)
3.3V_POWER_SUPPLY 4mV/count
3.28V
820
0-4.092V
4mV/count 1.4% 280ppm/°C
12 (0C)
DISC_MULTI_SPE 0.1*(4mV/count-Pedestal)


3
0-4.092V
4mV/count 1.4% 280ppm/°C
13 (0D)
FADC_OFFSET 2mV/count
1.704V
852
0-2.047V
2mV/count  1LSB 7ppm/°C
14 (0E)
LED_ANODE_VOLTAGE 20mV/count
When disabled,~0V
When enabled 3.3 - 20.105V
depending on DAC setting
18
0-20.47V
20mV/count 1.6%  320ppm/°C
15 (0F)
ATWD0_CAPTURE_SPEED_CTL
2mV/count
0.520V 260
0-2.047V
2mV/count  1LSB 7ppm/°C
16 (10)
ATWD0_RAMP_TOP_VOLTAGE
5mV/count
2.56V
511
0-5.115V 
5mV/count 1.4%  280ppm/°C
17 (11)
ATWD0_RAMP_RATE_CTL 2mV/count
0.37V
184
0-2.047V
2mV/count  1LSB 7ppm/°C
18 (12)
ANALOG_REF_VOLTAGE
5mV/count
2.49V
498
0-5.115V 
5mV/count 1.4%  280ppm/°C
19 (13)
ATWD1_CAPTURE_SPEED_CTL
2mV/count
0.52V 260
0-2.047V
2mV/count  1LSB 7ppm/°C
20 (14)
ATWD1_RAMP_TOP_VOLTAGE
5mV/count
2.56V
511
0-5.115V 
5mV/count 1.4%  280ppm/°C
21 (15)
ATWD1_RAMP_RATE_CTL
2mV/count
0.37V
184
0-2.047V
2mV/count  1LSB 7ppm/°C
22 (16)
PEDESTAL_VOLTAGE
5mV/count
2.345V
469
0-5.115V 
5mV/count 1.4%  280ppm/°C
23 (17)
TEST_PULSE_VOLTAGE
5mV/count
0 Except when calibrating.
Same as DAC Voltage when calibrating.
Expect values up to
5V_POWER_SUPPLY-
0
0-5.115V 
5mV/count 1.4%  280ppm/°C

Note 1,  .p = 111.111*(Vout/Vs)+10.555556 in kiloPascals  where Vout is the channel 2 ADC reading in counts, and Vs is the channel 3 ADC reading in counts. 
Note 2.  (Vp - Vs) * 0.4 mV/count = 0.08 SPE/count where Vp is pedestal voltage, and Vs is Single SPE DAC output voltage.
Note 3.  (Vp - Vs) * 0.4 mV/count = 0.08 SPE/count where Vp is pedestal voltage, and Vs is Multi SPE DAC output voltage.
Note 4  3.3V supply is 96% efficient at 200mA and below, and 92% efficient at 1000mA
Note 5  2.5V supply is 90% efficient at 100mA
Note 6  1.8V supply is 96% efficient at 200mA and below.

References:
IceBoot Users Guide, Arthur Jones
Forth Users Guide for DOMs, Arthur Jones