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12
4.5.1
DC Voltage Checks For Model 871A
1. Battery: VBAT > 7 V
2. Power Supplies:
V + to
È
(Analog Ground) = +2.8 ± 0.4 V
V + to
È
(Digital Ground) = +5 ± 1 V
3. Reference Diode: CR101 to
È
(Analog Ground) = -1.23 ± 0.03 V
4. Negative Reference Divider: (Reference to
È
Analog Ground)
R119
Pin
mV*
Pin
mV*
Pin
mV*
2
-210
5
-204
8
-195
3
-209
6
-199
9
-186
4
-204
7
-198
10
-173
*The setting of R104 and the tolerances of the resistors within the network
(R119) can affect these levels by ± 5%.
5. Deintegrate Comparators:
U103A PIN 3 to
È
= 150 ±25mV
U103B, PIN 6 to
È
= -150 ± 25 mV
6. Cold Junction Voltage:
(Ambient temperature 25º ±3ºC)
-COM to
È
= 1.0 ±0.6 mV
4.5.2
DC Voltage Checks For Model 872A
1. Battery: VBAT > 7 V
2. Power Supplies:
V + to
È
(Analog Ground) = +2.8 ± 0.4 V
V + to
È
(Digital Ground) = +5 + 1 V
3. Reference Diode: CR101 to
È
(Analog Ground)= -1.23 ±0.03 V
4. Negative Reference Divider: (Reference to
È
Analog Ground)
R119
Pin
mV*
Pin
mV*
Pin
mV*
2
-312
5
-274
8
-267
3
-293
6
-272
9
-254
4
-277
7
-271
10
-242
*The setting of R104 and the tolerances of the resistors within the network
(R119) can affect these levels by ±5%.
5. Deintegrate Comparators:
U103, Pin 3 to
È
=190 ±30 mV
U103B, Pin 6 to
È
= -180 ±30 mV
6. Cold Junction Voltage:
(Ambient temperature 25º ±3ºC)
-COM to
È
= 1.3 mV ±0.6
Содержание 871A
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