- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄10685 > LTC2494IUHF#PBF (Linear Technology)IC ADC 16BIT W/PGA 38-QFN PDF資料下載
參數(shù)資料
| 型號： | LTC2494IUHF#PBF |
| 廠商： | Linear Technology |
| 文件頁數(shù)： | 22/38頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC ADC 16BIT W/PGA 38-QFN |
| 標準包裝： | 52 |
| 位數(shù)： | 16 |
| 采樣率（每秒）： | 15 |
| 數(shù)據(jù)接口： | MICROWIRE?，串行，SPI? |
| 轉換器數(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 |
| 供應商設備封裝： | 38-QFN（5x7） |
| 包裝： | 管件 |
| 輸入數(shù)目和類型： | 16 個單端，雙極；8 個差分，雙極 |
| 產品目錄頁面： | 1348 (CN2011-ZH PDF) |
| 配用： | DC1011A-C-ND - BOARD DELTA SIGMA ADC LTC2494 |
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頁第19頁第20頁第21頁當前第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
LTC2494
2494fd
applications inForMation
larger source resistances. Source resistances up to 10k
mayinterfacedirectlytotheLTC2494andsettlecompletely;
however, the addition of external capacitors at the input
terminals in order to filter unwanted noise (anti-aliasing)
results in incomplete settling.
TheLTC2494offerstwomethodsofremovingtheseerrors.
The first is automatic differential input current cancella-
tion (Easy Drive) and the second is the insertion of buffer
between the MUXOUT and ADCIN pins, thus isolating the
input switching from the source resistance.
Automatic Differential Input Current Cancellation
In applications where the sensor output impedance is
low (up to 10k
Ω with no external bypass capacitor or up
to 500
Ω with 0.001F bypass), complete settling of the
input occurs. In this case, no errors are introduced and
direct digitization is possible.
For many applications, the sensor output impedance
combined with external input bypass capacitors produces
RC time constants much greater than the 580ns required
for 1ppm accuracy. For example, a 10k bridge driving a
0.1F capacitor has a time constant an order of magnitude
greater than the required maximum.
The LTC2494 uses a proprietary switching algorithm
that forces the average differential input current to zero
independent of external settling errors. This allows direct
digitization of high impedance sensors without the need
of buffers.
The switching algorithm forces the average input current
on the positive input (IIN+) to be equal to the average input
current in the negative input (IIN–). Over the complete
conversion cycle, the average input current (IIN+ – IIN–)
is zero. While the differential input current is zero, the
common mode input current (IIN+ + IIN–)/2 is proportional
to the difference between the common mode input volt-
age (VIN(CM)) and the common mode reference voltage
(VREF(CM)).
In applications where the input common mode voltage is
equal to the reference common mode voltage, as in the
case of a balanced bridge, both the differential and com-
mon mode input current are zero. The accuracy of the
converter is not compromised by settling errors.
In applications where the input common mode voltage is
constant but different from the reference common mode
voltage, the differential input current remains zero while
the common mode input current is proportional to the
Figure 12. LTC2494 Equivalent Analog Input Circuit
IN+
IN–
10k
INTERNAL
SWITCH
NETWORK
10k
CEQ
12pF
10k
IIN–
REF+
IREF+
IIN+
IREF–
2494 F12
SWITCHING FREQUENCY
fSW = 123kHz INTERNAL OSCILLATOR
fSW = 0.4 fEOSC EXTERNAL OSCILLATOR
REF–
10k
100
INPUT
MULTIPLEXER
EXTERNAL
CONNECTION
100
MUXOUTP
ADCINP
EXTERNAL
CONNECTION
MUXOUTN
ADCINN
I IN+
( )
AVG
=
I IN–
( )
AVG
=
VIN(CM) VREF(CM)
0.5REQ
I REF+
(
)
AVG
≈
1.5VREF + VREF(CM) – VIN(CM)
(
)
0.5 REQ
–
VIN2
VREF REQ
where:
VREF =REF
+ REF
VREF(CM) =
REF+ – REF
2
VIN =IN
+ IN, WHERE IN+ ANDIN ARE THE SELECTEDINPUT CHANNELS
VIN(CM) =
IN+ –IN
2
REQ =2.71MΩINTERNAL OSCILLATOR 60Hz MODE
REQ =2.98MΩINTERNAL OSCILLATOR 50Hz/60Hz MODE
REQ = 0.8331012
(
)/fEOSC EXTERNAL OSCILLATOR
相關PDF資料 |
PDF描述 |
|---|---|
| VE-272-IX-B1 | CONVERTER MOD DC/DC 15V 75W |
| VI-JWJ-MY-F4 | CONVERTER MOD DC/DC 36V 50W |
| LT1017IS8 | IC COMPARATOR MICRPWR DUAL 8SOIC |
| AD7321BRUZ | IC ADC 12BIT+ SAR 2CHAN 14TSSOP |
| AD7914BRUZ | IC ADC 10BIT 4CH 1MSPS 16TSSOP |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| LTC2495CUHF | 制造商:Linear Technology 功能描述:ADC Single Delta-Sigma 15sps 16-bit Serial 38-Pin QFN EP |
| LTC2495CUHF#PBF | 功能描述:IC ADC 16BIT W/PGA 38-QFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉換器 系列:- 標準包裝:1,000 系列:- 位數(shù):16 采樣率（每秒）:45k 數(shù)據(jù)接口:串行 轉換器數(shù)目:2 功率耗散（最大）:315mW 電壓電源:模擬和數(shù)字 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-SOIC（0.295"，7.50mm 寬） 供應商設備封裝:28-SOIC W 包裝:帶卷 (TR) 輸入數(shù)目和類型:2 個單端，單極 |
| LTC2495CUHF#TRPBF | 功能描述:IC ADC 16BIT W/PGA 38-QFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉換器 系列:- 標準包裝: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 供應商設備封裝: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 |
| LTC2495IUHF#PBF | 功能描述:IC ADC 16BIT W/PGA 38-QFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉換器 系列:- 標準包裝: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 供應商設備封裝: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 產品目錄頁面:892 (CN2011-ZH PDF) 其它名稱:296-25851-6 |
| LTC2495IUHF#TRPBF | 功能描述:IC ADC 16BIT W/PGA 38-QFN RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉換器 系列:- 標準包裝:1,000 系列:- 位數(shù):16 采樣率（每秒）:45k 數(shù)據(jù)接口:串行 轉換器數(shù)目:2 功率耗散（最大）:315mW 電壓電源:模擬和數(shù)字 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:28-SOIC（0.295"，7.50mm 寬） 供應商設備封裝:28-SOIC W 包裝:帶卷 (TR) 輸入數(shù)目和類型:2 個單端，單極 |
發(fā)布緊急采購，3分鐘左右您將得到回復。