参数资料
型号: AD7805CRZ-REEL7
厂商: Analog Devices Inc
文件页数: 9/28页
文件大小: 0K
描述: IC DAC 10BIT QUAD PARALL 28-SOIC
产品培训模块: Data Converter Fundamentals
DAC Architectures
标准包装: 400
设置时间: 1.5µs
位数: 10
数据接口: 并联
转换器数目: 4
电压电源: 模拟和数字
功率耗散(最大): 66mW
工作温度: -40°C ~ 85°C
安装类型: 表面贴装
封装/外壳: 28-SOIC(0.295",7.50mm 宽)
供应商设备封装: 28-SOIC W
包装: 带卷 (TR)
输出数目和类型: 8 电压,双极
采样率(每秒): 667k
AD7804/AD7805/AD7808/AD7809
–17–
REV. A
Table VII shows the twos complement transfer function for the
Sub DAC. Figure 23 shows the Sub DAC transfer function for
twos complement coding. Any Sub DAC output voltage can be
expressed as:
VOUT" = VBIAS/16
× (NB/256)
where NB is the decimal equivalent of the twos complement
input code. NB ranges from –128 to +127.
Table VII. Twos Complement Code Table for Sub DAC
Digital Input
Analog Input
MSB . . . LSB
01111111
(VBIAS/16)
× (127/256)
01111111
(VBIAS/16)
× (126/256)
00000001
(VBIAS/16)
× (1/256)
00000000
0
11111111
(–VBIAS/16)
× (1/256)
10000001
(–VBIAS/16)
× (127/256)
10000000
(–VBIAS/16)
× (128/256)
127
VBIAS
256
16
0
DAC
OUTPUT
VOLTAGE
128
VBIAS
256
16
80
81
DAC INPUT CODE
FF
00
01
7E
7F
Figure 23. Sub DAC Output Voltage vs. DAC Input Codes
(HEX) for Twos Complement Coding
The total output for a single channel when using twos comple-
ment coding is the sum of the voltage from the Main DAC and
the Sub DAC.
VOUT = VOUT' + VOUT"
= VBIAS + 1.875
× V
BIAS
× (NA/1024) + V
BIAS/16
× (NB/256)
= VBIAS
× (1 + 1.875 × NA/1024 + NB/4096)
where NA ranges from –512 to +511 and NB ranges from –128 to
+127. Figure 28 shows a pictorial view of the transfer function for
any DAC.
Configuring the AD7805/AD7809 for Twos Complement Coding
Figure 24 shows a typical configuration for the AD7805/AD7809.
The circuit can be used for either 3.3 V or 5 V operation and uses
the internal VDD/2 as the reference for the part and 10-bit paral-
lel interfacing is used. The following are the steps required to
operate the Main DACs in this part.
0.01 F
AD7805/
AD7809
AVDD
DVDD
VOUTA
VOUTB
VOUTC
VOUTD
AGND
DGND
LDAC
CLR
COMP
MODE
D9
D0
CS
WR
DVDD
REFIN
REFOUT
0.1 F
10 F
A1
A0
0.01 F
A2*
*USED ON THE
AD7809 ONLY
DIGITAL
INTERFACE
+3.3V/+5V
Figure 24. Typical Configuration for AD7805/AD7809
System Control Register Write:
MODE = 0, address inputs (A2, A1, A0) are don’t cares.
Write 020 Hex
Configure part for 10-bit parallel, twos
complement coding, normal operation
Channel Control Register Write:
MODE = 0, address inputs (A2, A1, A0) select desired channel.
Write 011 Hex
Internal VDD/2 selected as VBIAS for
DAC, and any DAC data writes that
follow are to the Main DAC.
DAC Data Register Write:
MODE = 1, address inputs (A2, A1, A0) select desired channel.
Write XXX Hex
With MODE = 1 all data writes are to
the selected DAC. XXX is the required
data. 200 Hex will give zero scale and 1FF
Hex will give full scale from the DAC.
相关PDF资料
PDF描述
MAX3761EEP+ IC AMP LIMITING 622MBPS 20-QSOP
MAX3762EEP+ IC AMP LIMITING 622MBPS 20-QSOP
MAX3268CUB+ IC AMP LIMITING 1.25GBPS 10-UMAX
LTC1667CG#TRPBF IC D/A CONV 14BIT 50MSPS 28-SSOP
LTC1667CG#TR IC D/A CONV 14BIT 50MSPS 28-SSOP
相关代理商/技术参数
参数描述
AD7806 制造商:未知厂家 制造商全称:未知厂家 功能描述:AD7804/AD7805/AD7806/AD7809: +3.3 V to +5 V Quad/Octal 10-Bit DACs Datasheet (Rev. A.12/98)
AD7808 制造商:AD 制造商全称:Analog Devices 功能描述:+3.3 V to +5 V Quad/Octal 10-Bit DACs
AD7808BN 制造商:Analog Devices 功能描述:DAC 8-CH 10-bit 24-Pin PDIP Tube 制造商:Analog Devices 功能描述:10BIT DAC OCTAL SERIAL 7808 DIP24
AD7808BNZ 功能描述:IC DAC 10BIT OCTAL SERIAL 24DIP RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 标准包装:2,400 系列:- 设置时间:- 位数:18 数据接口:串行 转换器数目:3 电压电源:模拟和数字 功率耗散(最大):- 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:36-TFBGA 供应商设备封装:36-TFBGA 包装:带卷 (TR) 输出数目和类型:* 采样率(每秒):*
AD7808BNZ 制造商:Analog Devices 功能描述:10BIT DAC OCTAL SERIAL 7808 DIP24