参数资料
型号: 101-0814
厂商: Rabbit Semiconductor
文件页数: 20/94页
文件大小: 0K
描述: COMPUTER SNG BD BL1810 512K SRAM
标准包装: 10
系列: SBC
模块/板类型: 单板计算机模块
适用于相关产品: BL1810
User’s Manual
23
3.4 D/A Converters
Two digital-to-analog (D/A) converter outputs, DA0 and DA1, are supplied on the Jack-
rabbit. These are shown in Figure 10.
The D/A converters have no reference voltage. Although they may be fairly accurate from
one programmed voltage to the next, they do not have absolute accuracy. This is because
Vcc can change ±5%, the PWM outputs might not achieve the full 0 V and 5 V rail out of
the processor, and the gain resistors in the circuit have a 1% tolerance. The D/A converters
therefore need individual calibration, with the calibration constants held in software
before absolute accuracy can be relied on. The Jackrabbit is sold without such calibration.
Figure 10. Schematic Diagram of D/A Converters
Note that DA0 is used to provide a reference voltage for the A/D converter and is unavail-
able for D/A conversion when the A/D converter is being used.
Pulse-width modulation (PWM) is used for the D/A conversion. This means that the digi-
tal signal, which is either 0 V or 5 V, is a train of pulses. This means that if the signal is
taken to be usually at 0 V (or ground), there will be 5 V pulses. The voltage will be 0 V for
a given time, then jump to 5 V for a given time, then back to ground for a given time, then
back to 5 V, and so on. A hardware filter in the circuit consisting of a resistor and capacitor
averages the 5 V signal and the 0 V signal over time. Therefore, if the time that the signal
is at 5 V is equal to the time the signal is 0 V, the duty cycle will be 50%, and the average
signal will be 2.5 V. If the time at 5 V is only 25% of the time, then the average voltage
will be 1.25 V. Thus, the software needs to only vary the time the signal is at 5 V with
respect to the time the signal is at 0 V to achieve any desired voltage between 0 V and 5 V.
+
Vcc
LM324
R29
1 MW
PD2
PD1
R22
10 kW
2
3
1
R26
82.5 kW
DA0
R20
1.1 kW
R27
255 kW
C20
100 nF
R21
110 kW
+
LM324
PD4
DA1
1.1 kW
100 nF
R24
100 kW
C22
R25
R28
100 kW
5
6
7
相关PDF资料
PDF描述
101-1007 MODULE POWERCORE FLEX 3810
101-1028 MODULE RABBITCORE RCM3750
101-1087 MODULE RABBITCORE RCM 3365
1B31AN IC SIGNAL COND STRAIN GAGE 28DIP
1B32AN IC SIGNAL COND HYBRID 28-DIP
相关代理商/技术参数
参数描述
101-0815 功能描述:单板计算机 SR9100 512K SRAM RoHS:否 制造商:Ampro By ADLINK 外观尺寸:EPIC 处理器类型:Intel Atom D510 频率:1.66 GHz 存储容量:2 GB (max) 存储类型:DDR2, L2 Cache 接口类型:Ethernet, PS/2, SATA, Serial, USB 工作电源电压:5 V, 12 V 功耗:13 W 最大工作温度:+ 70 C 尺寸:165.1 mm x 114.3 mm
101-0816 功能描述:KIT DEV RABBITCORE TCP/IP 2000 RoHS:否 类别:编程器,开发系统 >> 过时/停产零件编号 系列:* 标准包装:1 系列:- 类型:MCU 适用于相关产品:Freescale MC68HC908LJ/LK(80-QFP ZIF 插口) 所含物品:面板、缆线、软件、数据表和用户手册 其它名称:520-1035
101-0817 功能描述:单板计算机 BL2030 512K SRAM RoHS:否 制造商:Ampro By ADLINK 外观尺寸:EPIC 处理器类型:Intel Atom D510 频率:1.66 GHz 存储容量:2 GB (max) 存储类型:DDR2, L2 Cache 接口类型:Ethernet, PS/2, SATA, Serial, USB 工作电源电压:5 V, 12 V 功耗:13 W 最大工作温度:+ 70 C 尺寸:165.1 mm x 114.3 mm
101-0818 功能描述:单板计算机 BL2100 Fric Lk 512K RoHS:否 制造商:Ampro By ADLINK 外观尺寸:EPIC 处理器类型:Intel Atom D510 频率:1.66 GHz 存储容量:2 GB (max) 存储类型:DDR2, L2 Cache 接口类型:Ethernet, PS/2, SATA, Serial, USB 工作电源电压:5 V, 12 V 功耗:13 W 最大工作温度:+ 70 C 尺寸:165.1 mm x 114.3 mm
101-0820 功能描述:COMPUTER SGL-BD BL2000 SRAM/FLSH RoHS:否 类别:集成电路 (IC) >> 嵌入式 - 微控制器或微处理器模块 系列:SBC 产品目录绘图:DLP-245SY-G 标准包装:1 系列:USB 模块/板类型:开发板 适用于相关产品:USB 其它名称:813-1006