參數(shù)資料
型號: EVAL-AD7156EBZ
廠商: Analog Devices Inc
文件頁數(shù): 4/28頁
文件大小: 0K
描述: BOARD EVAL FOR AD7156
標(biāo)準(zhǔn)包裝: 1
傳感器類型: 觸摸,電容式
接口: I²C
電源電壓: 1.8 V ~ 3.6 V
嵌入式:
已供物品: 板,CD
已用 IC / 零件: AD7156
AD7156
Rev. 0 | Page 12 of 28
COMPARATOR AND THRESHOLD MODES
The AD7156 comparators and their thresholds can be
programmed to operate in two modes: fixed and adaptive
threshold modes. In an adaptive mode, the threshold
is dynamically adjusted and the comparator output indicates
fast changes and ignores slow changes in the input (sensor)
capacitance. Alternatively, the threshold can be programmed
as a constant (fixed) value, and the output then indicates any
change in the input capacitance that crosses the defined fixed
threshold.
The AD7156 logic output (active high) indicates either a positive or
a negative change in the input capacitance, in both adaptive and
fixed threshold modes (see Figure 25 and Figure 26).
POSITIVE
THRESHOLD
INPUT
CAPACITANCE
OUTPUT
OUTPUT ACTIVE
TIME
POSITIVE CHANGE
07
72
6-
03
3
Figure 25. Positive Threshold Mode
Indicates Positive Change in Input Capacitance
NEGATIVE
THRESHOLD
INPUT
CAPACITANCE
OUTPUT
OUTPUT ACTIVE
TIME
NEGATIVE CHANGE
07
72
6-
03
4
Figure 26. Negative Threshold Mode
Indicates Negative Change in Input Capacitance
Additionally, for the adaptive mode only, the comparators can
work as window comparators, indicating input either inside or
outside a selected sensitivity band (see Figure 27 and Figure 28).
POSITIVE
THRESHOLD
NEGATIVE
THRESHOLD
INPUT CAPACITANCE
OUTPUT
OUTPUT ACTIVE
TIME
INPUT INSIDE THRESHOLD WINDOW
07
72
6-
03
5
Figure 27. In-Window (Adaptive) Threshold Mode
POSITIVE
THRESHOLD
NEGATIVE
THRESHOLD
INPUT CAPACITANCE
OUTPUT
OUTPUT ACTIVE
TIME
INPUT OUTSIDE THRESHOLD WINDOW
07
72
6-
03
6
Figure 28. Out-Window (Adaptive) Threshold Mode
ADAPTIVE THRESHOLD
In an adaptive mode, the thresholds are dynamically adjusted,
ensuring indication of fast changes (for example, an object
moving close to a capacitive proximity sensor) and eliminating
slow changes in the input (sensor) capacitance, usually caused
by environment changes such as humidity or temperature or
changes in the sensor dielectric material over time (see Figure 29).
THRESHOLD
INPUT CAPACITANCE
OUTPUT
OUTPUT ACTIVE
TIME
FAST CHANGE
SLOW CHANGE
07
72
6-
03
7
Figure 29. Adaptive Threshold Indicates Fast Changes and Eliminates Slow
Changes in Input Capacitance
SENSITIVITY
In adaptive threshold mode, the output comparator threshold
is set as a defined distance (sensitivity) above the data average,
below the data average, or both, depending on the selected
threshold mode of operation (see Figure 30). The sensitivity
value is programmable in the range of 0 LSB to 255 LSB of the
12-bit CDC converter (see the Register Descriptions section).
NEGATIVE
THRESHOLD
POSITIVE
THRESHOLD
DATA AVERAGE
OUTPUT ACTIVE
TIME
SENSITIVITY
DATA
SENSITIVITY
0
77
26
-0
39
Figure 30. Threshold Sensitivity
相關(guān)PDF資料
PDF描述
MRJ0300DF-A C/A MRJ21/MRJ21 GBE ANGL CMR 30M
DEMO9RS08KA2 DEMO BOARD FOR 9RS08KA2
VE-J1B-EZ CONVERTER MOD DC/DC 95V 25W
EBC28DREH CONN EDGECARD 56POS .100 EYELET
ECC35DCMN CONN EDGECARD 70POS .100 WW
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
EVAL-AD7156EBZ 制造商:Analog Devices 功能描述:EVAL BOARD, AD7156 2CH CAPACITANCE CONVE
EVAL-AD7170EBZ 功能描述:BOARD EVAL FOR AD7170 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - 模數(shù)轉(zhuǎn)換器 (ADC) 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:- ADC 的數(shù)量:1 位數(shù):12 采樣率(每秒):94.4k 數(shù)據(jù)接口:USB 輸入范圍:±VREF/2 在以下條件下的電源(標(biāo)準(zhǔn)):- 工作溫度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,軟件
EVAL-AD7171EBZ 功能描述:BOARD EVAL FOR AD7171 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估板 - 模數(shù)轉(zhuǎn)換器 (ADC) 系列:- 產(chǎn)品培訓(xùn)模塊:Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1 系列:- ADC 的數(shù)量:1 位數(shù):12 采樣率(每秒):94.4k 數(shù)據(jù)接口:USB 輸入范圍:±VREF/2 在以下條件下的電源(標(biāo)準(zhǔn)):- 工作溫度:-40°C ~ 85°C 已用 IC / 零件:MAX11645 已供物品:板,軟件
EVAL-AD7173-8SDZ 制造商:Analog Devices 功能描述:EVAL BOARD MULTI CHANNEL - Boxed Product (Development Kits)
EVAL-AD7175-8SDZ 功能描述:AD7175-8 - 24 Bit 250k Samples per Second Analog to Digital Converter (ADC) Evaluation Board 制造商:analog devices inc. 系列:- 零件狀態(tài):有效 A/D 轉(zhuǎn)換器數(shù):1 位數(shù):24 采樣率(每秒):250k 數(shù)據(jù)接口:并聯(lián) 輸入范圍:±VREF 不同條件下的功率(典型值):105mW @ 250kSPS 使用的 IC/零件:AD7175-8 所含物品:板,電源 標(biāo)準(zhǔn)包裝:1