- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄10343 > AD7920BKSZ-REEL (Analog Devices Inc)IC ADC 12BIT SRL 250KSPS SC70-6 PDF資料下載
參數(shù)資料
| 型號： | AD7920BKSZ-REEL |
| 廠商： | Analog Devices Inc |
| 文件頁數(shù)： | 6/24頁 |
| 文件大?。?/td> | 0K |
| 描述： | IC ADC 12BIT SRL 250KSPS SC70-6 |
| 標準包裝： | 10,000 |
| 位數(shù)： | 12 |
| 采樣率（每秒）： | 250k |
| 數(shù)據(jù)接口： | DSP，MICROWIRE?，QSPI?，串行，SPI? |
| 轉(zhuǎn)換器數(shù)目： | 1 |
| 功率耗散（最大）： | 15mW |
| 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： | 6-TSSOP，SC-88，SOT-363 |
| 供應(yīng)商設(shè)備封裝： | SC-70-6 |
| 包裝： | 帶卷 (TR) |
| 輸入數(shù)目和類型： | 1 個單端，單極 |
| 配用： | EVAL-AD7920CBZ-ND - BOARD EVALUATION FOR AD7920 |
AD7910/AD7920
Rev. C | Page 14 of 24
CONVERTER OPERATION
The AD7910/AD7920 are successive approximation analog-to-
digital converters based around a charge redistribution DAC.
ADC. Figure 14 shows the ADC during its acquisition phase.
When SW2 is closed and SW1 is in Position A, the comparator
is held in a balanced condition, and the sampling capacitor
acquires the signal on VIN.
CHARGE
REDISTRIBUTION
DAC
CONTROL
LOGIC
COMPARATOR
SW2
SAMPLING
CAPACITOR
ACQUISITION
PHASE
SW1
A
B
AGND
VDD/2
VIN
02976-014
Figure 14. ADC Acquisition Phase
When the ADC starts a conversion (see Figure 15), SW2 opens
and SW1 moves to Position B, causing the comparator to become
unbalanced. The control logic and charge redistribution DAC are
used to add and subtract fixed amounts of charge from the
sampling capacitor to bring the comparator back into a balanced
condition. When the comparator is rebalanced, the conversion is
complete. The control logic generates the ADC output code.
Figure 16 shows the ADC transfer function.
CHARGE
REDISTRIBUTION
DAC
CONTROL
LOGIC
COMPARATOR
SW2
SAMPLING
CAPACITOR
CONVERSION
PHASE
SW1
A
B
AGND
VDD/2
VIN
02976-015
Figure 15. ADC Conversion Phase
ADC TRANSFER FUNCTION
The output coding of the AD7910/AD7920 is straight binary.
The designed code transitions occur at the successive integer
LSB values, that is, 1 LSB, 2 LSBs, and so on. The LSB size is
VDD/4096 for the AD7920 and VDD/1024 for the AD7910. The
ideal transfer characteristic for the AD7910/AD7920 is shown
in Figure 16.
000...000
0V
ADC
CODE
ANALOG INPUT
111...111
000...001
000...010
111...110
111...000
011...111
1LSB
+VDD – 1LSB
1LSB = VDD/1024 (AD7910)
1LSB = VDD/4096 (AD7920)
02976-016
Figure 16. Transfer Characteristic
TYPICAL CONNECTION DIAGRAM
Figure 17 shows a typical connection diagram for the AD7910/
AD7920. VREF is taken internally from VDD and, as such, VDD
should be well decoupled. This provides an analog input range of
0 V to VDD. The conversion result is output in a 16-bit word with
four leading zeros followed by the MSB of the 12-bit or 10-bit
result. Two trailing zeros follow the 10-bit result from the
AD7910.
Alternatively, because the supply current required by the
AD7910/AD7920 is so low, a precision reference can be used as
the supply source to the AD7910/AD7920. An REF19x voltage
supply the required voltage to the ADC (see Figure 17). This
configuration is especially useful if the power supply is quite
noisy or if the system supply voltages are at a value other than
5 V or 3 V (for example, 15 V). The REF19x outputs a steady
voltage to the AD7910/AD7920. If the low dropout REF193 is
used, the current it needs to supply to the AD7910/AD7920 is
typically 1.2 mA. When the ADC is converting at a rate of
250 kSPS, the REF193 needs to supply a maximum of 1.4 mA to
the AD7910/AD7920. The load regulation of the REF193 is
typically 10 ppm/mA (REF193, VS = 5 V), which results in an
error of 14 ppm (42 μV) for the 1.4 mA drawn from it. This
corresponds to a 0.057 LSB error for the AD7920 with VDD =
3 V from the REF193 and a 0.014 LSB error for the AD7910.
For applications where power consumption is of concern, the
power-down mode of the ADC and the sleep mode of the
REF19x reference should be used to improve power
performance. See the Modes of Operation section.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MS27473E10F35SD | CONN PLUG 13POS STRAIGHT W/SCKT |
| AD7477AARMZ-REEL | IC ADC 10BIT 1MSPS 8-MSOP |
| MS27473E10F35SB | CONN PLUG 13POS STRAIGHT W/SCKT |
| LTC2481HDD#PBF | IC ADC 16BIT I2C 7.5SPS 10DFN |
| MS27499E10B99P | CONN RCPT 7POS BOX MNT W/PINS |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AD7920BKSZ-REEL7 | 功能描述:IC ADC 12BIT SRL 250KSPS SC70-6 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(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 |
| AD7920BRM | 制造商:Analog Devices 功能描述:ADC Single SAR 250ksps 12-bit Serial 8-Pin MSOP 制造商:Rochester Electronics LLC 功能描述:12-BIT 250KSPS ADC MICRO SOIC PKG I.C. - Bulk 制造商:Analog Devices 功能描述:IC 12BIT ADC SMD 7920 MSOP8 |
| AD7920BRM-REEL | 制造商:Analog Devices 功能描述:ADC Single SAR 250ksps 12-bit Serial 8-Pin MSOP T/R |
| AD7920BRM-REEL7 | 制造商:Analog Devices 功能描述:ADC Single SAR 250ksps 12-bit Serial 8-Pin MSOP T/R |
| AD7920BRMZ | 功能描述:IC ADC 12BIT 250KSPS 8-MSOP 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(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 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。