- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄9737 > AD7148ACPZ-1500RL7 (Analog Devices Inc)IC CAP-TO-DGTL CONV PROG 16LFCSP PDF資料下載
參數(shù)資料
| 型號： | AD7148ACPZ-1500RL7 |
| 廠商： | Analog Devices Inc |
| 文件頁數(shù)： | 18/57頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC CAP-TO-DGTL CONV PROG 16LFCSP |
| 標準包裝： | 1 |
| 類型： | 電容性 |
| 觸摸面板接口： | 2 線 |
| 輸入數(shù)/鍵： | 8 鍵 |
| 分辨率（位）： | 16 b |
| 數(shù)據(jù)接口： | I²C，串行 |
| 數(shù)據(jù)速率/采樣率 (SPS，BPS)： | 250k |
| 電壓基準： | 內(nèi)部 |
| 電源電壓： | 2.6 V ~ 3.3 V |
| 工作溫度： | -40°C ~ 85°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 16-VQFN 裸露焊盤，CSP |
| 供應(yīng)商設(shè)備封裝： | 16-LFCSP |
| 包裝： | 標準包裝 |
| 產(chǎn)品目錄頁面： | 781 (CN2011-ZH PDF) |
| 其它名稱： | AD7148ACPZ-1500RL7DKR |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁當(dāng)前第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁
AD7148
Rev. A | Page 24 of 56
ADAPTIVE THRESHOLD AND SENSITIVITY
The AD7148 provides an on-chip self-learning adaptive threshold
and sensitivity algorithm. This algorithm continuously monitors
the output levels of each sensor and automatically rescales the
threshold levels proportionally to the sensor area covered by the
user. As a result, the AD7148 maintains optimal threshold and
sensitivity levels for all types of users, regardless of finger size.
The threshold level is always referenced from the ambient level
and is defined as the CDC converter output level that must be
exceeded for a valid sensor contact. The sensitivity level is defined
as how sensitive the sensor is before a valid contact is registered.
Figure 34 provides an example of how the adaptive threshold and
sensitivity algorithm works. The positive and negative sensor
threshold levels are calculated as a percentage of the STAGEx_
OFFSET_HIGH and STAGEx_OFFSET_LOW values, based
on the threshold sensitivity settings and the ambient value. On
configuration, initial estimates are supplied for both STAGEx_
OFFSET_HIGH and STAGEx_OFFSET_LOW, after which the
calibration engine automatically adjusts the STAGEx_HIGH_
THRESHOLD and STAGEx_LOW_THRESHOLD values for
sensor response.
The AD7148 tracks the average maximum and minimum values
measured from each sensor. These values give an indication of
how the user is interacting with the sensor. A large finger gives
a large average maximum or minimum value, and a small finger
gives smaller values. When the average maximum or minimum
value changes, the threshold levels are rescaled to ensure that
the threshold levels are appropriate for the current user. Figure 35
shows how the minimum and maximum sensor responses are
tracked by the on-chip logic.
Reference A in Figure 34 shows an undersensitive threshold
level for a small finger user, demonstrating the disadvantages of
a fixed threshold level.
By enabling the adaptive threshold and sensitivity algorithm, the
positive and negative threshold levels are determined by the
POS_THRESHOLD_SENSITIVITY and NEG_THRESHOLD_
SENSITIVITY values and the most recent average maximum
sensor output value. These bits can be used to select 16 different
positive and negative sensitivity levels ranging between 25% and
95.32% of the most recent average maximum output level
referenced from the ambient value. The smaller the sensitivity
percentage setting, the easier it is to trigger a sensor activation.
Reference B shows that the positive adaptive threshold level is set
at almost mid-sensitivity with a 62.51% threshold level by setting
POS_THRESHOLD_SENSITIVITY = 1000. Figure 34 also
provides a similar example for the negative threshold level with
NEG_THRESHOLD_SENSITIVITY = 0011.
A
AMBIENT LEVEL
CDC
O
U
T
P
UT
CO
D
E
S
25%
62.51% = POS ADAPTIVE
THRESHOLD LEVEL
95.32%
AVERAGE MAX VALUE
STAGEx_OFFSET_HIGH
25%
95.32%
62.51% = POS
ADAPTIVE
THRESHOLD LEVEL
NEG ADAPTIVE THRESHOLD LEVEL = 39.08%
25%
95.32%
25%
95.32%
SENSOR CONTACTED
BY SMALL FINGER
VERAGE MAX VALUE
STAGEx_OFFSET_LOW
NEG ADAPTIVE THRESHOLD LEVEL = 39.08%
SENSOR CONTACTED
BY LARGE FINGER
071
55-
033
STAGEx_OFFSET_HIGH
IS UPDATED
A
STAGEx_OFFSET_HIGH
IS UPDATED HERE
B
STAGEx_OFFSET_LOW
IS UPDATED HERE
STAGEx_OFFSET_LOW
IS UPDATED HERE
Figure 34. Threshold Sensitivity Example with POS_THRESHOLD_SENSITIVITY = 1000 and NEG_THRESHOLD_SENSITIVITY = 0011
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MS27467P9B98SA | CONN PLUG 3POS STRAIGHT W/SCKT |
| VE-J1J-MX-F1 | CONVERTER MOD DC/DC 36V 75W |
| MS27484T10B35PB | CONN PLUG 13POS STRAIGHT W/PINS |
| SY100E416JI | IC LINE RCVR QUINT DIFF 28-PLCC |
| MS27467T15F19PD | CONN PLUG 19POS STRAIGHT W/PINS |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AD7148ACPZ-1REEL | 功能描述:IC CAP-TO-DGTL CONV PROG 16LFCSP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 觸摸屏控制器 系列:- 標準包裝:96 系列:- 類型:- 觸摸面板接口:- 輸入數(shù)/鍵:- 分辨率（位）:- 評估套件:* 數(shù)據(jù)接口:- 數(shù)據(jù)速率/采樣率 (SPS，BPS):- 電壓基準:- 電源電壓:- 電流 - 電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:16-TSSOP（0.173"，4.40mm 寬） 供應(yīng)商設(shè)備封裝:16-TSSOP 包裝:帶卷 (TR) |
| AD7150 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Ultra Low Power, 2 Channel, Capacitance Converter for Proximity Sensing |
| AD7150BRMZ | 功能描述:IC CAP CONV 2CH ULT LP 10MSOP RoHS:是 類別:集成電路 (IC) >> 接口 - 傳感器和探測器接口 系列:- 其它有關(guān)文件:Automotive Product Guide 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:74 系列:- 類型:觸控式傳感器 輸入類型:數(shù)字 輸出類型:數(shù)字 接口:JTAG，串行 電流 - 電源:100µA 安裝類型:表面貼裝 封裝/外殼:20-TSSOP（0.173"，4.40mm 寬） 供應(yīng)商設(shè)備封裝:20-TSSOP 包裝:管件 |
| AD7150BRMZ-REEL | 功能描述:IC CAP CONV 2CH ULT LP 10MSOP RoHS:是 類別:集成電路 (IC) >> 接口 - 傳感器和探測器接口 系列:- 其它有關(guān)文件:Automotive Product Guide 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:74 系列:- 類型:觸控式傳感器 輸入類型:數(shù)字 輸出類型:數(shù)字 接口:JTAG，串行 電流 - 電源:100µA 安裝類型:表面貼裝 封裝/外殼:20-TSSOP（0.173"，4.40mm 寬） 供應(yīng)商設(shè)備封裝:20-TSSOP 包裝:管件 |
| AD7151 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Ultra-Low Power, 1-Channel, Capacitance Converter for Proximity Sensing |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。