- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄15531 > EVAL-ADUC842QSZ (Analog Devices Inc)KIT DEV QUICK START ADUC842 PDF資料下載
參數(shù)資料
| 型號(hào)： | EVAL-ADUC842QSZ |
| 廠商： | Analog Devices Inc |
| 文件頁(yè)數(shù)： | 21/88頁(yè) |
| 文件大小： | 0K |
| 描述： | KIT DEV QUICK START ADUC842 |
| 標(biāo)準(zhǔn)包裝： | 1 |
| 系列： | QuickStart™ 套件 |
| 類(lèi)型： | MCU |
| 適用于相關(guān)產(chǎn)品： | ADuC824 |
| 所含物品： | 評(píng)估板、電源、纜線、軟件和說(shuō)明文檔 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)當(dāng)前第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)
ADuC841/ADuC842/ADuC843
Rev. 0 | Page 28 of 88
Table 11. Some Single-Supply Op Amps
Op Amp Model
Characteristics
OP281/OP481
Micropower
OP191/OP291/OP491
I/O Good up to VDD, Low Cost
OP196/OP296/OP496
I/O to VDD, Micropower, Low Cost
OP183/OP283
High Gain-Bandwidth Product
OP162/OP262/OP462
High GBP, Micro Package
AD820/AD822/AD824
FET Input, Low Cost
AD823
FET Input, High GBP
Keep in mind that the ADC’s transfer function is 0 V to VREF,
and that any signal range lost to amplifier saturation near
ground will impact dynamic range. Though the op amps in
Table 11 are capable of delivering output signals that very
closely approach ground, no amplifier can deliver signals all the
way to ground when powered by a single supply. Therefore, if a
negative supply is available, you might consider using it to
power the front end amplifiers. If you do, however, be sure to
include the Schottky diodes shown in Figure 31 (or at least the
lower of the two diodes) to protect the analog input from
undervoltage conditions. To summarize this section, use the
circuit in Figure 31 to drive the analog input pins of the parts.
Voltage Reference Connections
The on-chip 2.5 V band gap voltage reference can be used as the
reference source for the ADC and DACs. To ensure the accuracy
of the voltage reference, you must decouple the CREF pin to
ground with a 0.47 F capacitor, as shown in Figure 32. Note
that this is different from the ADuC812/ADuC831/ADuC832.
BUFFER
0.47
F
51
VREF = NC
CREF
2.5V
BAND GAP
REFERENCE
ADuC841/ADuC842/ADuC843
03260-0-030
Figure 32. Decoupling VREF and CREF
If the internal voltage reference is to be used as a reference for
external circuitry, the CREF output should be used. However, a
buffer must be used in this case to ensure that no current is
drawn from the CREF pin itself. The voltage on the CREF pin is that
of an internal node within the buffer block, and its voltage is
critical for ADC and DAC accuracy. The parts power up with
their internal voltage reference in the off state.
If an external voltage reference is preferred, it should be
connected to the CREF pin as shown in Figure 33. Bit 6 of the
ADCCON1 SFR must be set to 1 to switch in the external
reference voltage.
To ensure accurate ADC operation, the voltage applied to CREF
must be between 1 V and AVDD. In situations where analog
input signals are proportional to the power supply (such as in
some strain gage applications), it may be desirable to connect
the CREF pin directly to AVDD. Operation of the ADC or DACs
with a reference voltage below 1 V, however, may incur loss of
accuracy, eventually resulting in missing codes or non-
monotonicity. For that reason, do not use a reference voltage
lower than 1 V.
BUFFER
51
CREF
EXTERNAL
VOLTAGE
REFERENCE
1 = EXTERNAL
0 = INTERNAL
0.1
F
2.5V
BAND GAP
REFERENCE
ADuC841/ADuC842/ADuC843
ADCCON1.6
VDD
03260-0-031
VREF = NC
Figure 33. Using an External Voltage Reference
Configuring the ADC
The parts’ successive approximation ADC is driven by a divided
down version of the master clock. To ensure adequate ADC
operation, this ADC clock must be between 400 kHz and
8.38 MHz. Frequencies within this range can be achieved easily
with master clock frequencies from 400 kHz to well above
16 MHz, with the four ADC clock divide ratios to choose from.
For example, set the ADC clock divide ratio to 8 (i.e., ADCCLK
= 16.777216 MHz/8 = 2 MHz) by setting the appropriate bits in
ADCCON1 (ADCCON1.5 = 1, ADCCON1.4 = 0). The total
ADC conversion time is 15 ADC clocks, plus 1 ADC clock for
synchronization, plus the selected acquisition time (1, 2, 3, or 4
ADC clocks). For the preceding example, with a 3-clock
acquisition time, total conversion time is 19 ADC clocks (or
9.05 s for a 2 MHz ADC clock).
In continuous conversion mode, a new conversion begins each
time the previous one finishes. The sample rate is then simply
the inverse of the total conversion time described previously. In
the preceding example, the continuous conversion mode sample
rate is 110.3 kHz.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AIUR-06-4R7K | INDUCTOR POWER 4.7UH 10% T/H |
| V110C8C75BL3 | CONVERTER MOD DC/DC 8V 75W |
| EVAL-ADUC842QS | KIT DEV FOR ADUC842 QUICK START |
| V110C8C75BL | CONVERTER MOD DC/DC 8V 75W |
| AIUR-09-821K | INDUCTOR POWER 820UH 10% T/H |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| EVAL-ADUC845QS | 制造商:Analog Devices 功能描述:QUICK START DEVELOPMENT SYSTEM - Bulk |
| EVAL-ADUC845QSP | 制造商:Analog Devices 功能描述:MICROCONVERTER?, 1-CYCLE 8052 MCU + 10-CHANNEL, DUAL 24-BIT - Bulk |
| EVAL-ADUC845QSPZ | 功能描述:KIT DEV QUICK START ADUC845 RoHS:是 類(lèi)別:編程器，開(kāi)發(fā)系統(tǒng) >> 通用嵌入式開(kāi)發(fā)板和套件（MCU、DSP、FPGA、CPLD等） 系列:QuickStart™ PLUS 套件 產(chǎn)品培訓(xùn)模塊:Blackfin® Processor Core Architecture Overview Blackfin® Device Drivers Blackfin® Optimizations for Performance and Power Consumption Blackfin® System Services 特色產(chǎn)品:Blackfin? BF50x Series Processors 標(biāo)準(zhǔn)包裝:1 系列:Blackfin® 類(lèi)型:DSP 適用于相關(guān)產(chǎn)品:ADSP-BF548 所含物品:板，軟件，4x4 鍵盤(pán)，光學(xué)撥輪，QVGA 觸摸屏 LCD 和 40G 硬盤(pán) 配用:ADZS-BFBLUET-EZEXT-ND - EZ-EXTENDER DAUGHTERBOARDADZS-BFLLCD-EZEXT-ND - BOARD EXT LANDSCAP LCD INTERFACE 相關(guān)產(chǎn)品:ADSP-BF542BBCZ-4A-ND - IC DSP 16BIT 400MHZ 400CSBGAADSP-BF544MBBCZ-5M-ND - IC DSP 16BIT 533MHZ MDDR 400CBGAADSP-BF542MBBCZ-5M-ND - IC DSP 16BIT 533MHZ MDDR 400CBGAADSP-BF542KBCZ-6A-ND - IC DSP 16BIT 600MHZ 400CSBGAADSP-BF547MBBCZ-5M-ND - IC DSP 16BIT 533MHZ MDDR 400CBGAADSP-BF548BBCZ-5A-ND - IC DSP 16BIT 533MHZ 400CSBGAADSP-BF547BBCZ-5A-ND - IC DSP 16BIT 533MHZ 400CSBGAADSP-BF544BBCZ-5A-ND - IC DSP 16BIT 533MHZ 400CSBGAADSP-BF542BBCZ-5A-ND - IC DSP 16BIT 533MHZ 400CSBGA |
| EVAL-ADUC845QSZ | 功能描述:KIT DEV FOR ADUC845 QUICK START RoHS:是 類(lèi)別:編程器，開(kāi)發(fā)系統(tǒng) >> 通用嵌入式開(kāi)發(fā)板和套件（MCU、DSP、FPGA、CPLD等） 系列:QuickStart™ 套件 標(biāo)準(zhǔn)包裝:1 系列:PICDEM™ 類(lèi)型:MCU 適用于相關(guān)產(chǎn)品:PIC10F206，PIC16F690，PIC16F819 所含物品:板，線纜，元件，CD，PICkit 編程器 產(chǎn)品目錄頁(yè)面:659 (CN2011-ZH PDF) |
| EVAL-ADUC846QS | 制造商:AD 制造商全稱(chēng):Analog Devices 功能描述:MicroConverter, Dual 16-Bit ADCs with Embedded 62kB FLASH MCU |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。