- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄10687 > LTC2484IDD#PBF (Linear Technology)IC ADC 24BIT 10-DFN PDF資料下載
參數(shù)資料
| 型號： | LTC2484IDD#PBF |
| 廠商： | Linear Technology |
| 文件頁數(shù)： | 19/42頁 |
| 文件大小： | 0K |
| 描述： | IC ADC 24BIT 10-DFN |
| 標(biāo)準(zhǔn)包裝： | 121 |
| 位數(shù)： | 24 |
| 采樣率（每秒）： | 6.8 |
| 數(shù)據(jù)接口： | MICROWIRE?，串行，SPI? |
| 轉(zhuǎn)換器數(shù)目： | 1 |
| 功率耗散（最大）： | 480µW |
| 電壓電源： | 單電源 |
| 工作溫度： | -40°C ~ 85°C |
| 安裝類型： | 表面貼裝 |
| 封裝/外殼： | 10-WFDFN 裸露焊盤 |
| 供應(yīng)商設(shè)備封裝： | 10-DFN（3x3） |
| 包裝： | 管件 |
| 輸入數(shù)目和類型： | 1 個差分，雙極 |
| 產(chǎn)品目錄頁面： | 1348 (CN2011-ZH PDF) |
| 配用： | DC939A-ND - BOARD DELTA SIGMA ADC LTC2484 |
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頁第18頁當(dāng)前第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
LTC2484
26
2484fd
APPLICATIONS INFORMATION
Driving the Input and Reference
The input and reference pins of the LTC2484 converter
are directly connected to a network of sampling capaci-
tors. Depending upon the relation between the differential
input voltage and the differential reference voltage, these
capacitors are switching between these four pins transfer-
ring small amounts of charge in the process. A simplied
equivalent circuit is shown in Figure 11.
For a simple approximation, the source impedance RS
driving an analog input pin (IN+, IN–, VREF+ or GND)
can be considered to form, together with RSW and CEQ
(see Figure 11), a rst order passive network with a time
constant
τ = (RS + RSW) CEQ. The converter is able to
sample the input signal with better than 1ppm accuracy
if the sampling period is at least 14 times greater than the
input circuit time constant,
τ. The sampling process on
the four input analog pins is quasi-independent so each
time constant should be considered by itself and, under
worst-case circumstances, the errors may add.
When using the internal oscillator, the LTC2484’s front-end
switched-capacitor network is clocked at 123kHz corre-
sponding to an 8.1μs sampling period. Thus, for settling
errors of less than 1ppm, the driving source impedance
should be chosen such that
τ ≤ 8.1μs/14 = 580ns. When an
external oscillator of frequency fEOSC is used, the sampling
period is 2.5/fEOSC and, for a settling error of less than
1ppm,
τ ≤ 0.178/fEOSC.
Automatic Differential Input Current Cancellation
In applications where the sensor output impedance is
low (up to 10kΩ with no external bypass capacitor or up
to 500Ω with 0.001μF bypass), complete settling of the
input occurs. In this case, no errors are introduced and
direct digitization of the sensor is possible.
For many applications, the sensor output impedance
combined with external bypass capacitors produces RC
time constants much greater than the 580ns required
for 1ppm accuracy. For example, a 10kΩ bridge driving
a 0.1μF bypass capacitor has a time constant an order of
magnitude greater than the required maximum. Historically,
settling issues were solved using buffers. These buffers
led to increased noise, reduced DC performance (Offset/
Drift), limited input/output swing (cannot digitize signals
near ground or VCC), added system cost and increased
power. The LTC2484 uses a proprietary switching algo-
VREF
+
VIN
+
VCC
RSW (TYP)
10k
ILEAK
VCC
ILEAK
VCC
RSW (TYP)
10k
CEQ
12pF
(TYP)
RSW (TYP)
10k
ILEAK
IIN
+
VIN
–
IIN
–
IREF
+
IREF
–
2484 F11
ILEAK
VCC
ILEAK
SWITCHING FREQUENCY
fSW = 123kHz INTERNAL OSCILLATOR
fSW = 0.4 fEOSC EXTERNAL OSCILLATOR
GND
RSW (TYP)
10k
Figure 11. LTC2484 Equivalent Analog Input Circuit
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC2485IDD#PBF | IC ADC 24BIT I2C 10-DFN |
| LTC1443CDHD#TRPBF | IC COMP W/REF LOW PWR QUAD 16DFN |
| LTC1444CDHD#TRPBF | IC COMP QD LP 1.221VREF 16-DFN |
| AD9200ARSZ | IC ADC 10BIT CMOS 20MSPS 28-SSOP |
| LTC1445CDHD#TRPBF | IC COMP QD LP 1.221VREF 16-DFN |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC2485CDD#PBF | 功能描述:IC ADC 24BIT I2C 10-DFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1 系列:microPOWER™ 位數(shù):8 采樣率（每秒）:1M 數(shù)據(jù)接口:串行，SPI? 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:- 電壓電源:模擬和數(shù)字 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:24-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:24-VQFN 裸露焊盤（4x4） 包裝:Digi-Reel® 輸入數(shù)目和類型:8 個單端，單極 產(chǎn)品目錄頁面:892 (CN2011-ZH PDF) 其它名稱:296-25851-6 |
| LTC2485CDD#TRPBF | 功能描述:IC ADC 24BIT I2C 10-DFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:2,500 系列:- 位數(shù):12 采樣率（每秒）:3M 數(shù)據(jù)接口:- 轉(zhuǎn)換器數(shù)目:- 功率耗散（最大）:- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應(yīng)商設(shè)備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數(shù)目和類型:- |
| LTC2485IDD | 制造商:Linear Technology 功能描述:ADC Single Delta-Sigma 7.5sps 24-bit Serial 10-Pin DFN EP |
| LTC2485IDD#PBF | 功能描述:IC ADC 24BIT I2C 10-DFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1 系列:microPOWER™ 位數(shù):8 采樣率（每秒）:1M 數(shù)據(jù)接口:串行，SPI? 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:- 電壓電源:模擬和數(shù)字 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:24-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:24-VQFN 裸露焊盤（4x4） 包裝:Digi-Reel® 輸入數(shù)目和類型:8 個單端，單極 產(chǎn)品目錄頁面:892 (CN2011-ZH PDF) 其它名稱:296-25851-6 |
| LTC2485IDD#TRPBF | 功能描述:IC ADC 24BIT I2C 10-DFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 位數(shù):16 采樣率（每秒）:15 數(shù)據(jù)接口:MICROWIRE?，串行，SPI? 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:480µW 電壓電源:單電源 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:38-WFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:38-QFN（5x7） 包裝:帶卷 (TR) 輸入數(shù)目和類型:16 個單端，雙極；8 個差分，雙極 配用:DC1011A-C-ND - BOARD DELTA SIGMA ADC LTC2494 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。