AMC7812BSPAP datasheet(47/92 Pages) TI1

47 / 92 page

HighThreshold

LowThreshold

Hysteresis

Input

Hysteresis

OverHighAlarm

BelowLowAlarm

AMC7812B

www.ti.com

SBAS625A – SEPTEMBER 2013 – REVISED SEPTEMBER 2013

Hysteresis

The device continuously monitors the analog input channels and temperatures. If any alarms are out of range

and the alarm is enabled, the alarm bit is set ('1'). However, the alarm condition is cleared only when the

conversion result returns to a value of at least hys below the value of the high threshold register, or hys above

the value of low threshold register. The hysteresis registers store the value for each analog input (CH0, CH1,

CH2, and CH3) and temperature (D1, D2, and LT). hys is the value of hysteresis that is programmable: 0 LSB to

127 LSB for analog inputs, and 0°C to +31°C for temperatures. For the THERM-ALR bit, the hysteresis is fixed at

8°C. The hysteresis behavior is shown in Figure 98.

Figure 98. Hysteresis

False-Alarm Protection

As noted previously, the device continuously monitors all analog inputs and temperatures in normal operation.

When any input is out of the specified range in N consecutive conversions, the corresponding alarm bit is set

('1'). If the input returns to the normal range before N consecutive times, the alarm bit remains clear ('0'). This

design avoids false alarms.

The number N is programmable by the CH-FALR-CT-[2:0] bits in AMC configuration register 1 for analog input

CHn as shown in Table 6, or by the TEMP-FALR-CT-[1:0] bits for temperature monitors as shown in Table 7.

Table 6. Consecutive Sample Number for False Alarm Protection for CHn

N CONSECUTIVE SAMPLES

CH-FALR-CT-2

CH-FALR-CT-1

CH-FALR-CT-0

BEFORE ALARM IS SET

16 (default)

128

256

Table 7. Consecutive Sample Number for False Alarm Protection for Temperature Channels

TEMP-FALR-CT-1

TEMP-FALR-CT-0

N CONSECUTIVE SAMPLES BEFORE ALARM IS SET

4 (default)

Submit Documentation Feedback

Product Folder Links: AMC7812B

AMC7812BSPAP Datasheet(PDF) 47 Page - Texas Instruments

AMC7812BSPAP Datasheet(HTML) 47 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92

Datasheet Download

Link URL