- 您現在的位置：買賣IC網 > PDF目錄374038 > ADUC7027AST62 (ANALOG DEVICES INC) Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU PDF資料下載
參數資料
| 型號： | ADUC7027AST62 |
| 廠商： | ANALOG DEVICES INC |
| 元件分類： | 微控制器/微處理器 |
| 英文描述： | Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU |
| 中文描述： | 32-BIT, FLASH, 45.5 MHz, MICROCONTROLLER, PQFP80 |
| 封裝： | PLASTIC, LQFP-80 |
| 文件頁數： | 38/80頁 |
| 文件大小： | 840K |
| 代理商： | ADUC7027AST62 |
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頁當前第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頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁
ADuC702x Series
Preliminary Technical Data
Rev. PrB | Page 38 of 80
Using the DACs
The on-chip DAC architecture consists of a resistor string DAC
followed by an output buffer amplifier, the functional
equivalent of which is illustrated in Figure 17.
OUTPUT
BUFFER
BYPASSED
FROM MCU
DAC0
R
R
R
R
R
AVDD
VREF
DACREF
Figure 17: DAC structure
As illustrated in Figure 17, the reference source for each DAC is
user selectable in software. It can be either AVDD, VREF or
DACREF. In 0-to-AVDD mode, the DAC output transfer
function spans from 0 V to the voltage at the AVDD pin. In 0-
to-DACREF mode, the DAC output transfer function spans
from 0 V to the voltage at the DACREF pin. In 0-to-VREF
mode, the DAC output transfer function spans from 0 V to the
internal 2.5V reference, VREF. The DAC output buffer amplifier
features a true rail-to-rail output stage implementation. This
means that, unloaded, each output is capable of swinging to
within less than 5 mV of both AVDD and ground. Moreover,
the DAC’s linearity specification (when driving a 5k resistive
load to ground) is guaranteed through the full transfer function
except codes 0 to 100, and, in 0-to-AVDD mode only, codes
3995 to 4095. Linearity degradation near ground and VDD is
caused by saturation of the output amplifier, and a general
representation of its effects (neglecting offset and gain error) is
illustrated in Figure 18. The dotted line in Figure 18 indicates
the ideal transfer function, and the solid line represents what
the transfer function might look like with endpoint
nonlinearities due to saturation of the output amplifier. Note
that Figure 18 represents a transfer function in 0-to-AV
DD
mode
only. In 0-to-V
REF
or 0-to-DAC
REF
modes (with V
REF
< AV
DD
or
DAC
REF
< AV
DD
) the lower nonlinearity would be similar, but
the upper portion of the transfer function would follow the
“ideal” line right to the end (V
REF
in this case, not AV
DD
),
showing no signs of endpoint linearity errors.
AV
DD
AV
DD
-100mV
100mV
000h
FFFh
~
~
~
Figure 18: endpoint nonlinearities due to amplifier saturation
The endpoint nonlinearities conceptually illustrated in Figure
18 get worse as a function of output loading. Most of the
ADuC702x’s datasheet specifications assume a 5 k
resistive
load to ground at the DAC output. As the output is forced to
source or sink more current, the nonlinear regions at
the top or bottom (respectively) of Figure 18 become larger.
With larger current demands, this can significantly limit output
voltage swing.
To reduce the effects of the saturation of the output amplifier at
values close to ground and to give reduced offset and gain
errors, the internal buffer can be bypassed in the DAC control
register. This allows a full rail-to-rail output from the DAC
which should then be buffered externally using a dual supply
op-amp in order to get a rail-to-rail output. This external buffer
should be located as near as physically possible to the DAC
output pin on the PCB.
相關PDF資料 |
PDF描述 |
|---|---|
| ADUC7027BST62 | Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU |
| ADUC702X | Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU |
| ADUC7020 | Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU |
| ADUC702 | 5 AMP MINIATURE POWER RELAY |
| ADUC814ARU-REEL7 | Circular Connector; MIL SPEC:MIL-DTL-38999 Series I; Body Material:Metal; Series:LJT; No. of Contacts:37; Connector Shell Size:25; Connecting Termination:Crimp; Circular Shell Style:Jam Nut Receptacle; Body Style:Straight RoHS Compliant: No |
相關代理商/技術參數 |
參數描述 |
|---|---|
| ADUC7027ASTZ62 | 制造商:Analog Devices 功能描述:MCU 32BIT RISC 62KB FLASH 3.3V 80LQFP - Trays |
| ADUC7027BST62 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU |
| ADUC7027BSTZ62 | 功能描述:IC MCU FLASH 62K ANLG I/0 80LQFP RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器， 系列:MicroConverter® ADuC7xxx 標準包裝:250 系列:LPC11Uxx 核心處理器:ARM? Cortex?-M0 芯體尺寸:32-位 速度:50MHz 連通性:I²C，Microwire，SPI，SSI，SSP，UART/USART，USB 外圍設備:欠壓檢測/復位，POR，WDT 輸入/輸出數:40 程序存儲器容量:96KB（96K x 8） 程序存儲器類型:閃存 EEPROM 大小:4K x 8 RAM 容量:10K x 8 電壓 - 電源 (Vcc/Vdd):1.8 V ~ 3.6 V 數據轉換器:A/D 8x10b 振蕩器型:內部 工作溫度:-40°C ~ 85°C 封裝/外殼:48-LQFP 包裝:托盤 其它名稱:568-9587 |
| ADUC7027BSTZ62I | 功能描述:IC MCU FLASH 62K ANLG I2C 80LQFP RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器， 系列:MicroConverter® ADuC7xxx 標準包裝:38 系列:Encore!® XP® 核心處理器:eZ8 芯體尺寸:8-位 速度:5MHz 連通性:IrDA，UART/USART 外圍設備:欠壓檢測/復位，LED，POR，PWM，WDT 輸入/輸出數:16 程序存儲器容量:4KB（4K x 8） 程序存儲器類型:閃存 EEPROM 大小:- RAM 容量:1K x 8 電壓 - 電源 (Vcc/Vdd):2.7 V ~ 3.6 V 數據轉換器:- 振蕩器型:內部 工作溫度:-40°C ~ 105°C 封裝/外殼:20-SOIC（0.295"，7.50mm 寬） 包裝:管件 其它名稱:269-4116Z8F0413SH005EG-ND |
| ADUC7027BSTZ62I-RL | 制造商:Analog Devices 功能描述: |
發布緊急采購，3分鐘左右您將得到回復。