参数资料
型号: AD5415YRU
厂商: Analog Devices Inc
文件页数: 10/29页
文件大小: 0K
描述: IC DAC DUAL 12BIT MULT 24-TSSOP
产品培训模块: Data Converter Fundamentals
DAC Architectures
标准包装: 62
设置时间: 120ns
位数: 12
数据接口: 串行
转换器数目: 2
电压电源: 单电源
功率耗散(最大): 3.5µW
工作温度: -40°C ~ 125°C
安装类型: 表面贴装
封装/外壳: 24-TSSOP(0.173",4.40mm 宽)
供应商设备封装: 24-TSSOP
包装: 管件
输出数目和类型: 4 电流,单极;4 电流,双极
采样率(每秒): 2.47M
Data Sheet
AD5415
Rev. E | Page 17 of 28
Positive Output Voltage
The output voltage polarity is opposite to the VREF polarity for
dc reference voltages. To achieve a positive voltage output, an
applied negative reference to the input of the DAC is preferred
over the output inversion through an inverting amplifier
because of the resistors’ tolerance errors. To generate a negative
reference, the reference can be level-shifted by an op amp such
that the VOUT and GND pins of the reference become the virtual
ground and 2.5 V, respectively, as shown in Figure 37.
VDD
RFBA
IOUT1A
IOUT2A
C1
VOUT = 0 TO +2.5V
GND
VDD = 5V
VREFA
NOTES
1. ADDITIONAL PINS OMITTED FOR CLARITY.
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED
IF A1 IS A HIGH SPEED AMPLIFIER.
12-BIT DAC
ADR03
VOUT
VIN
GND
–5V
+5V
–2.5V
04461-036
Figure 37. Positive Voltage Output with Minimum of Components
ADDING GAIN
In applications where the output voltage must be greater than VIN,
gain can be added with an additional external amplifier, or it can
be achieved in a single stage. Consider the effect of temperature
coefficients of the thin film resistors of the DAC. Simply placing
a resistor in series with the RFB resistor causes mismatches in the
temperature coefficients, resulting in larger gain temperature
coefficient errors. Instead, the circuit in Figure 38 shows the
recommended method for increasing the gain of the circuit.
R1, R2, and R3 should have similar temperature coefficients,
but they need not match the temperature coefficients of the
DAC. This approach is recommended in circuits where gains
of greater than 1 are required.
VDD
RFBA
IOUT1A
IOUT2A
C1
GND
VDD
VREFA
NOTES
1. ADDITIONAL PINS OMITTED FOR CLARITY.
2. C1 PHASE COMPENSATION (1pF TO 2pF) MAY BE REQUIRED
IF A1 IS A HIGH SPEED AMPLIFIER.
12-BIT DAC
VIN
R1
R3
R2
VOUT
R1 =
R2R3
R2 + R3
GAIN =
R2 + R3
R2
04461-037
Figure 38. Increasing the Gain of the Current Output DAC
DIVIDER OR PROGRAMMABLE GAIN ELEMENT
Current-steering DACs are very flexible and lend themselves to
many applications. If this type of DAC is connected as the
feedback element of an op amp and RFB is used as the input
resistor, as shown in Figure 39, the output voltage is inversely
proportional to the digital input fraction, D.
For D equal to 1 2n, the output voltage is
VOUT = VIN/D = VIN/(1 2n)
VIN
NOTES
1. ADDITIONAL PINS OMITTED FOR CLARITY.
VREFA
VDD
RFBA
IOUT1A
IOUT2A
GND
VOUT
04461-038
Figure 39. Current-Steering DAC Used as a Divider or
Programmable Gain Element
As D is reduced, the output voltage increases. For small
values of the digital fraction, D, it is important to ensure that
the amplifier does not saturate and that the required accuracy is
met. For example, an 8-bit DAC driven with the binary code 0x10
(0001 0000)—that is, 16 decimal—in the circuit of Figure 39
should cause the output voltage to be 16 times VIN. However, if
the DAC has a linearity specification of ±0.5 LSB, D can have a
weight in the range of 15.5/256 to 16.5/256, so that the possible
output voltage is in the range of 15.5 VIN to 16.5 VIN—an error of
3%, even though the DAC itself has a maximum error of 0.2%.
DAC leakage current is also a potential source of errors in
divider circuits. The leakage current must be counterbalanced
by an opposite current supplied from the op amp through the
DAC. Because only a fraction, D, of the current into the VREFA
terminal is routed to the IOUT1A terminal, the output voltage
changes as follows:
Output Error Voltage Due to DAC Leakage = (Leakage × R)/D
where R is the DAC resistance at the VREFA terminal.
For a DAC leakage current of 10 nA, R = 10 k, and a gain (that
is, 1/D) of 16, the error voltage is 1.6 mV.
相关PDF资料
PDF描述
AD5421CREZ IC DAC 16BIT SPI/SRL 28TSSOP
AD5422ACPZ-REEL7 IC DAC 16BIT SRL 40LFCSP
AD5441BRMZ-REEL7 IC DAC 12BIT SERIAL IN 8MSOP
AD5445YRU IC DAC 12BIT PARALL IOUT 20TSSOP
AD5446YRM IC DAC 14BIT MULTIPLYING 10-MSOP
相关代理商/技术参数
参数描述
AD5415YRU-REEL 制造商:Analog Devices 功能描述:DAC 2-CH R-2R 12-bit 24-Pin TSSOP T/R 制造商:Analog Devices 功能描述:DAC 2CH R-2R 12-BIT 24TSSOP - Tape and Reel
AD5415YRU-REEL7 功能描述:IC DAC DUAL 12BIT MULT 24-TSSOP RoHS:否 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 产品培训模块:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色产品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 标准包装:91 系列:- 设置时间:4µs 位数:10 数据接口:MICROWIRE?,串行,SPI? 转换器数目:8 电压电源:单电源 功率耗散(最大):2.7mW 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-DFN-EP(4x3) 包装:管件 输出数目和类型:8 电压,单极 采样率(每秒):*
AD5415YRUZ 功能描述:IC DAC DUAL 12BIT MULT 24-TSSOP RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:50 系列:- 设置时间:4µs 位数:12 数据接口:串行 转换器数目:2 电压电源:单电源 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:8-TSSOP,8-MSOP(0.118",3.00mm 宽) 供应商设备封装:8-uMAX 包装:管件 输出数目和类型:2 电压,单极 采样率(每秒):* 产品目录页面:1398 (CN2011-ZH PDF)
AD5415YRUZ-REEL 功能描述:IC DAC 12BIT DUAL MULT 24-TSSOP RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 产品培训模块:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色产品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 标准包装:91 系列:- 设置时间:4µs 位数:10 数据接口:MICROWIRE?,串行,SPI? 转换器数目:8 电压电源:单电源 功率耗散(最大):2.7mW 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-DFN-EP(4x3) 包装:管件 输出数目和类型:8 电压,单极 采样率(每秒):*
AD5415YRUZ-REEL7 功能描述:IC DAC 12BIT DUAL MULT 24-TSSOP RoHS:是 类别:集成电路 (IC) >> 数据采集 - 数模转换器 系列:- 产品培训模块:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色产品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 标准包装:91 系列:- 设置时间:4µs 位数:10 数据接口:MICROWIRE?,串行,SPI? 转换器数目:8 电压电源:单电源 功率耗散(最大):2.7mW 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-DFN-EP(4x3) 包装:管件 输出数目和类型:8 电压,单极 采样率(每秒):*