参数资料
型号: LTC2224CUK
厂商: Linear Technology
文件页数: 5/24页
文件大小: 0K
描述: IC ADC 12BIT 135MSPS SAMPL 48QFN
标准包装: 52
位数: 12
采样率(每秒): 135M
数据接口: 并联
转换器数目: 1
功率耗散(最大): 680mW
电压电源: 单电源
工作温度: 0°C ~ 70°C
安装类型: 表面贴装
封装/外壳: 48-WFQFN 裸露焊盘
供应商设备封装: 48-QFN-EP(7x7)
包装: 管件
输入数目和类型: 1 个单端,双极; 1 个差分,双极
LTC2224
13
2224fa
CONVERTER OPERATION
As shown in Figure 1, the LTC2224 is a CMOS pipelined
multistep converter. The converter has five pipelined ADC
stages; a sampled analog input will result in a digitized
value five cycles later (see the Timing Diagram section).
For optimal AC performance the analog inputs should be
driven differentially. For cost sensitive applications, the
analog inputs can be driven single-ended with slightly
worse harmonic distortion. The encode input is differen-
tial for improved common mode noise immunity. The
LTC2224 has two phases of operation, determined by the
state of the differential ENC+/ENCinput pins. For brevity,
the text will refer to ENC+ greater than ENCas ENC high
and ENC+ less than ENCas ENC low.
Each pipelined stage shown in Figure 1 contains an ADC,
a reconstruction DAC and an interstage residue amplifier.
In operation, the ADC quantizes the input to the stage and
the quantized value is subtracted from the input by the
DAC to produce a residue. The residue is amplified and
output by the residue amplifier. Successive stages operate
out of phase so that when the odd stages are outputting
their residue, the even stages are acquiring that residue
and vice versa.
When ENC is low, the analog input is sampled differentially
directly onto the input sample-and-hold capacitors, inside
the “Input S/H” shown in the block diagram. At the instant
that ENC transitions from low to high, the sampled input
is held. While ENC is high, the held input voltage is
buffered by the S/H amplifier which drives the first pipelined
ADC stage. The first stage acquires the output of the S/H
during this high phase of ENC. When ENC goes back low,
the first stage produces its residue which is acquired by
the second stage. At the same time, the input S/H goes
back to acquiring the analog input. When ENC goes back
high, the second stage produces its residue which is
acquired by the third stage. An identical process is re-
peated for the third and fourth stages, resulting in a fourth
stage residue that is sent to the fifth stage ADC for final
evaluation.
Each ADC stage following the first has additional range to
accommodate flash and amplifier offset errors. Results
from all of the ADC stages are digitally synchronized such
that the results can be properly combined in the correction
logic before being sent to the output buffer.
SAMPLE/HOLD OPERATION AND INPUT DRIVE
Sample/Hold Operation
Figure 2 shows an equivalent circuit for the LTC2224
CMOS differential sample-and-hold. The analog inputs are
connected to the sampling capacitors (CSAMPLE) through
NMOS transistors. The capacitors shown attached to each
input (CPARASITIC) are the summation of all other capaci-
tance associated with each input.
CSAMPLE
1.6pF
VDD
LTC2224
AIN
+
2224 F02
CSAMPLE
1.6pF
VDD
AIN
ENC
ENC+
1.6V
6k
1.6V
6k
CPARASITIC
1pF
CPARASITIC
1pF
15
15
Figure 2. Equivalent Input Circuit
APPLICATIO S I FOR ATIO
WU
UU
相关PDF资料
PDF描述
LT6300IGN#PBF IC XDSL LINE DRIVER 16-SSOP
LTC2369IDE-18#TRPBF IC ADC 18BIT SRL/SPI 1.6M 16-DFN
LTC2379IMS-18#TRPBF IC ADC 18BIT SPI/SRL 16MSOP
LTC2864HDD-2#PBF IC TRANSCEIVER RS485 10-DFN
LTC2379IDE-18#TRPBF IC ADC 18BIT SPI/SRL 16DFN
相关代理商/技术参数
参数描述
LTC2224CUK#PBF 功能描述:IC ADC 12BIT 135MSPS SAMPL 48QFN RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 其它有关文件:TSA1204 View All Specifications 标准包装:1 系列:- 位数:12 采样率(每秒):20M 数据接口:并联 转换器数目:2 功率耗散(最大):155mW 电压电源:模拟和数字 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-TQFP 供应商设备封装:48-TQFP(7x7) 包装:Digi-Reel® 输入数目和类型:4 个单端,单极;2 个差分,单极 产品目录页面:1156 (CN2011-ZH PDF) 其它名称:497-5435-6
LTC2224CUK#TR 功能描述:IC ADC 12BIT 135MSPS SAMPL 48QFN RoHS:否 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1 系列:- 位数:14 采样率(每秒):83k 数据接口:串行,并联 转换器数目:1 功率耗散(最大):95mW 电压电源:双 ± 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:28-DIP(0.600",15.24mm) 供应商设备封装:28-PDIP 包装:管件 输入数目和类型:1 个单端,双极
LTC2224CUK#TRPBF 功能描述:IC ADC 12BIT 135MSPS SAMPL 48QFN RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1 系列:- 位数:14 采样率(每秒):83k 数据接口:串行,并联 转换器数目:1 功率耗散(最大):95mW 电压电源:双 ± 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:28-DIP(0.600",15.24mm) 供应商设备封装:28-PDIP 包装:管件 输入数目和类型:1 个单端,双极
LTC2224IUK 功能描述:IC ADC 12BIT 135MSPS SAMPL 48QFN RoHS:否 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1 系列:- 位数:14 采样率(每秒):83k 数据接口:串行,并联 转换器数目:1 功率耗散(最大):95mW 电压电源:双 ± 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:28-DIP(0.600",15.24mm) 供应商设备封装:28-PDIP 包装:管件 输入数目和类型:1 个单端,双极
LTC2224IUK#PBF 功能描述:IC ADC 12BIT 135MSPS SAMPL 48QFN RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模数转换器 系列:- 标准包装:1 系列:- 位数:14 采样率(每秒):83k 数据接口:串行,并联 转换器数目:1 功率耗散(最大):95mW 电压电源:双 ± 工作温度:0°C ~ 70°C 安装类型:通孔 封装/外壳:28-DIP(0.600",15.24mm) 供应商设备封装:28-PDIP 包装:管件 输入数目和类型:1 个单端,双极