- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄374039 > ADUC824 (Analog Devices, Inc.) MicroConverter, Dual-Channel 16-/24-Bit ADCs with Embedded FLASH MCU PDF資料下載
參數(shù)資料
| 型號(hào)： | ADUC824 |
| 廠商： | Analog Devices, Inc. |
| 元件分類： | 串行ADC |
| 英文描述： | MicroConverter, Dual-Channel 16-/24-Bit ADCs with Embedded FLASH MCU |
| 中文描述： | MicroConverter的，雙通道ADC的16-/24-Bit與嵌入式閃存MCU |
| 文件頁數(shù)： | 34/68頁 |
| 文件大?。?/td> | 1060K |
| 代理商： | ADUC824 |
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頁當(dāng)前第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
REV. B
ADuC824
–34–
The absolute input voltage range on the auxiliary ADC is restricted
to between AGND – 30 mV to AVDD + 30 mV. The slightly
negative absolute input voltage limit does allow the possibility of
monitoring small signal bipolar signals using the single-ended
auxiliary ADC front end.
Programmable Gain Amplifier
The output from the buffer on the primary ADC is applied to the
input of the on-chip programmable gain amplifier (PGA). The
PGA can be programmed through eight different unipolar input
ranges and bipolar ranges. The PGA gain range is programmed
via the range bits in the ADC0CON SFR. With the external refer-
ence select bit set in the ADC0CON SFR and an external 2.5V
reference, the unipolar ranges are 0 mV to 20 mV, 0 mV to
40 mV, 0 mV to 80 mV, 0 mV to 160 mV, 0 mV to 320 mV,
0 mV to 640 mV, 0 V to 1.28 V, and 0 to 2.56 V, while the
bipolar ranges are
±
20 mV,
±
40 mV,
±
80 mV,
±
160 mV,
±
320 mV,
±
640 mV,
±
1.28 V, and
±
2.56 V. These are the
nominal ranges that should appear at the input to the on-chip
PGA. An ADC range matching specification of 2
μ
V (typ) across
all ranges means that calibration need only be carried out at a
single gain range and does not have to be repeated when the
PGA gain range is changed.
Typical matching across ranges is shown in Figure 20 below.
Here, the primary ADC is configured in bipolar mode with an
external 2.5 V reference, while just greater than 19 mV is forced
on its inputs. The ADC continuously converts the DC input
voltage at an update rate of 5.35 Hz, i.e., SF = FFhex. In total,
800 conversion results are gathered. The first 100 results are
gathered with the primary ADC operating in the
±
20 mV range.
The ADC range is then switched to
±
40 mV and 100 more con-
version results are gathered, and so on until the last group of
100 samples are gathered with the ADC configured in the
±
2.56 V
range. From Figure 20, The variation in the sample mean
through each range, i.e., the range matching, is seen to be of
the order of 2
μ
V.
The auxiliary ADC does not incorporate a PGA and is configured
for a fixed single input range of 0 to V
REF
.
0
100
200
300
400
500
600
700
800
SAMPLE COUNT
A
–
19.372
19.371
19.370
19.369
19.368
19.367
19.366
19.365
19.364
ADC RANGE
2
4
8
1
3
6
1
2
Figure 20. Primary ADC Range Matching
Bipolar/Unipolar Inputs
The analog inputs on the ADuC824 can accept either unipolar or
bipolar input voltage ranges. Bipolar input ranges do not imply that
the part can handle negative voltages with respect to system AGND.
Unipolar and bipolar signals on the AIN(+) input on the primary
ADC are referenced to the voltage on the respective AIN(–) input.
For example, if AIN(–) is 2.5 V and the primary ADC is config-
ured for an analog input range of 0 mV to 20 mV, the input
voltage range on the AIN(+) input is 2.5 V to 2.52 V. If AIN(–)
is 2.5 V and the ADuC824 is configured for an analog input range
of 1.28 V, the analog input range on the AIN(+) input is 1.22 V
to 3.78 V (i.e., 2.5 V
±
1.28 V).
As mentioned earlier, the auxiliary ADC input is a single-ended
input with respect to the system AGND. In this context a bipolar
signal on the auxiliary ADC can only span 30 mV negative with
respect to AGND before violating the voltage input limits for
this ADC.
Bipolar or unipolar options are chosen by programming the
Primary and Auxiliary Unipolar enable bits in the ADC0CON
and ADC1CON SFRs respectively. This programs the relevant
ADC for either unipolar or bipolar operation. Programming for
either unipolar or bipolar operation does not change any of the
input signal conditioning; it simply changes the data output coding
and the points on the transfer function where calibrations occur.
When an ADC is configured for unipolar operation, the output
coding is natural (straight) binary with a zero differential input
voltage resulting in a code of 000 . . . 000, a midscale voltage
resulting in a code of 100 . . . 000, and a full-scale input voltage
resulting in a code of 111 . . . 111. When an ADC is configured
for bipolar operation, the coding is offset binary with a negative
full-scale voltage resulting in a code of 000 . . . 000, a zero
differential voltage resulting in a code of 100 . . . 000, and a
positive full-scale voltage resulting in a code of 111 . . . 111.
Burnout Currents
The primary ADC on the ADuC824 contains two 100 nA con-
stant current generators, one sourcing current from AVDD to
AIN(+), and one sinking from AIN(–) to AGND. The currents
are switched to the selected analog input pair. Both currents are
either on or off, depending on the Burnout Current Enable
(BO) bit in the ICON SFR (see Table VIII). These currents can
be used to verify that an external transducer is still operational
before attempting to take measurements on that channel. Once
the burnout currents are turned on, they will flow in the exter-
nal transducer circuit, and a measurement of the input voltage
on the analog input channel can be taken. If the resultant volt-
age measured is full-scale, this indicates that the transducer has
gone open-circuit. If the voltage measured is 0 V, it indicates that
the transducer has short circuited. For normal operation, these
burnout currents are turned off by writing a 0 to the BO bit in
the ICON SFR. The current sources work over the normal abso-
lute input voltage range specifications.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ADUC824BS | MicroConverter, Dual-Channel 16-/24-Bit ADCs with Embedded FLASH MCU |
| ADUC831 | LJT 6C 6#22D PIN RECP |
| ADUC831BCP | Circular Connector; No. of Contacts:6; Series:LJT07R; Body Material:Aluminum; Connecting Termination:Crimp; Connector Shell Size:9; Circular Contact Gender:Socket; Circular Shell Style:Jam Nut Receptacle; Insert Arrangement:9-35 |
| ADUC831BS | MicroConverter, 12-Bit ADCs and DACs with Embedded 62 kBytes Flash MCU |
| ADUC836 | MicroConverter, Dual 16-Bit-ADCs with Embedded 62 kB Flash MCU |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ADUC824BCP | 制造商:Analog Devices 功能描述:MCU 8-Bit ADuC8xx 8052 CISC 8KB Flash 3.3V/5V 56-Pin LFCSP EP 制造商:Rochester Electronics LLC 功能描述:8BIT CISC 8KB FLASH 12.58MHZ 3.3/5V 56LFCSP - Bulk |
| ADUC824BCP-REEL | 制造商:Analog Devices 功能描述:MCU 8-Bit ADuC8xx 8052 CISC 8KB Flash 3.3V/5V 56-Pin LFCSP EP T/R |
| ADUC824BCPZ | 功能描述:IC MCU 8K FLASH ADC/DAC 56LFCSP RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器， 系列:MicroConverter® ADuC8xx 標(biāo)準(zhǔn)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(shè)備:欠壓檢測/復(fù)位，LED，POR，PWM，WDT 輸入/輸出數(shù):16 程序存儲(chǔ)器容量:4KB（4K x 8） 程序存儲(chǔ)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(shù)據(jù)轉(zhuǎn)換器:- 振蕩器型:內(nèi)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 |
| ADUC824BS | 制造商:Analog Devices 功能描述:MCU 8-bit ADuC8xx 8052 CISC 8KB Flash 3.3V/5V 52-Pin MQFP 制造商:Rochester Electronics LLC 功能描述:8BIT CISC 8KB FLASH 12.58MHZ 3.3/5V 52MQFP - Bulk 制造商:Analog Devices 功能描述:8BIT MCU +24BIT ADC LQFP52 824 |
| ADUC824BS-DEN | 制造商:Analog Devices 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。