and it is not referenced to ana" />
參數(shù)資料
型號: 20-101-1154
廠商: Rabbit Semiconductor
文件頁數(shù): 51/112頁
文件大?。?/td> 0K
描述: MODULE RCM4120 RABBITCORE
標(biāo)準(zhǔn)包裝: 1
系列: RabbitCore®
模塊/板類型: MPU 核心模塊
適用于相關(guān)產(chǎn)品: RCM4120
其它名稱: 316-1122
User’s Manual
39
If a device such as a battery is
connected across two channels
for a differential measurement,
and it is not referenced to
analog ground, then the current
from the device will flow
through both sets of attenuator
resistors without flowing back
to analog ground as shown in
Figure 10. This will generate a
negative voltage at one of the
inputs, LN1, which will almost
certainly lead to inaccurate A/D
conversions. To make such differential measurements, connect the R1 resistors to the A/D
converter’s internal reference voltage, which is software-configurable for 1.15 V, 2.048 V,
or 2.5 V. This internal reference voltage is available on pin 49 of header J3 as VREF, and
allows you to convert analog input voltages that are negative with respect to analog ground.
NOTE: The amplifier inside the A/D converter’s internal voltage reference circuit has a
very limited output-current capability. The internal buffer can source up to 20 mA and
sink only up to 200 A. Use a separate buffer amplifier if you need to supply any load
current.
The A/D converter’s CONVERT pin is available on pin 48 of header J3 and can be used as
a hardware means of forcing the A/D converter to start a conversion cycle at a specific time.
The CONVERT signal is an edge-triggered event and has a hold time of two CCLK periods
for debounce.
A conversion is started by an active (rising) edge on the CONVERT pin. The CONVERT
pin must stay low for at least two CCLK periods before going high for at least two CCLK
periods. Figure 11 shows the timing of a conversion start. The double falling arrow on
CCLK indicates the actual start of the conversion cycle.
Figure 11. Timing Diagram for Conversion Start Using CONVERT Pin
Appendix B.4.3 explains the implementation examples of these features on the Prototyp-
ing Board.
Figure 10. Current Flow from Ungrounded
or Floating Source
R5
R6
2.2 nF
R14
R13
2.2 nF
ADC
AIN0
AIN1
+
I
LN0
LN1
+
-
Device
CCLK
BUSY
CONV
Conversion starts
相關(guān)PDF資料
PDF描述
20-101-1197 MODULE RABBITCORE RCM3910 ROHS
20-101-1215 MCU RCM4050 RABBITCORE
20-101-1246 CORE MODULE RCM5400W
20-101-1260 BL5S220 SBC (RCM5400-BASED)
20-101-1319 MINCORE MODULE RCM6710
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
20-101-1170 功能描述:Zigbee/802.15.4模塊 RCM4510W CORE MODULE RoHS:否 制造商:Digi International 頻帶:902 MHz to 928 MHz 視線范圍: 數(shù)據(jù)速率: 靈敏度: 工作電源電壓:2.4 V to 3.6 V 傳輸供電電流:215 mA 接收供電電流:26 mA 輸出功率:250 mW 天線連接器類型:Wire 最大工作溫度:+ 85 C 尺寸:32.94 mm x 22 mm x 2.03 mm
20-101-1179 功能描述:模塊化系統(tǒng) - SOM RCM3209 RABBITCORE RoHS:否 制造商:Digi International 外觀尺寸:ConnectCore 9P 處理器類型:ARM926EJ-S 頻率:150 MHz 存儲容量:8 MB, 16 MB 存儲類型:NOR Flash, SDRAM 接口類型:I2C, SPI, UART 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 尺寸:1.97 in x 1.97 in x 6.1 in
20-101-1183 功能描述:程序設(shè)計(jì)器配件 USB PROGRAM CABLE RoHS:否 制造商:Lattice 產(chǎn)品:ispDOWNLOAD Cables 用于:In-system Programming
20-101-1184 功能描述:模塊化系統(tǒng) - SOM IC CPU RABBIT 2000 (2 pack) RoHS:否 制造商:Digi International 外觀尺寸:ConnectCore 9P 處理器類型:ARM926EJ-S 頻率:150 MHz 存儲容量:8 MB, 16 MB 存儲類型:NOR Flash, SDRAM 接口類型:I2C, SPI, UART 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 尺寸:1.97 in x 1.97 in x 6.1 in
20-101-1185 功能描述:微處理器 - MPU IC CPU RABBIT 3000A (2 pack) RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時(shí)鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:FBGA-324