參數(shù)資料
型號: LTC1409
廠商: Linear Technology Corporation
英文描述: 12-Bit, 800ksps Sampling A/D Converter with Shutdown(12位, 800ksps,采樣模數(shù)轉(zhuǎn)換器(帶關(guān)斷))
中文描述: 12位,800ksps與關(guān)機采樣A / D轉(zhuǎn)換器(12位,800ksps,采樣模數(shù)轉(zhuǎn)換器(帶關(guān)斷))
文件頁數(shù): 8/20頁
文件大?。?/td> 343K
代理商: LTC1409
8
LTC1409
APPLICATIO
S I
FOR
ATIO
U
CONVERSION DETAILS
W
U
U
The LTC1409 uses a successive approximation algorithm
and an internal sample-and-hold circuit to convert an
analog signal to a 12-bit parallel output. The ADC is
complete with a precision reference and an internal clock.
The control logic provides easy interface to microproces-
sors and DSPs. (Please refer to the Digital Interface
section for the data format.)
Conversion start is controlled by the CS and CONVST
inputs. At the start of the conversion the successive
approximation register (SAR) is reset. Once a conversion
cycle has begun it cannot be restarted.
During the conversion, the internal differential 12-bit
capacitive DAC output is sequenced by the SAR from the
most significant bit (MSB) to the least significant bit
(LSB). Referring to Figure 1, the +A
IN
and –A
IN
inputs are
connected to the sample-and-hold capacitors (C
SAMPLE
)
during the acquire phase and the comparator offset is
nulled by the zeroing switches. In this acquire phase, a
minimum delay of 150ns will provide enough time for the
sample-and-hold capacitors to acquire the analog signal.
During the convert phase the comparator zeroing switches
open, putting the comparator into compare mode. The
input switches connect the C
SAMPLE
capacitors to ground,
transferring the differential analog input charge onto the
summing junction. This input charge is successively com-
pared with the binary-weighted charges supplied by the
differential capacitive DAC. Bit decisions are made by the
high speed comparator. At the end of a conversion, the
differential DACs output balances the +A
IN
and –A
IN
input
charges. The SAR contents (a 12-bit data word) which
represents the difference of +A
IN
and –A
IN
are loaded into
the 12-bit output latches.
DYNAMIC PERFORMANCE
The LTC1409 has excellent high speed sampling capabil-
ity. FFT (Fast Four Transform) test techniques are used to
test the ADC’s frequency response, distortion and noise at
the rated throughput. By applying a low distortion sine
wave and analyzing the digital output using FFT algorithm,
the ADC’s spectral content can be examined for frequen-
cies outside the fundamental. Figure 2 shows typical
LTC1409 plots.
Figure 1. Simplified Block Diagram
COMP
+C
SAMPLE
–C
DAC
D11
D0
ZEROING SWITCHES
HOLD
HOLD
+A
IN
–A
IN
+C
DAC
–C
SAMPLE
12
LTC1409 F01
+
SAR
OUTPUT
LATCHES
+V
DAC
–V
DAC
HOLD
HOLD
Figure 2b. LTC1409 Nonaveraged, 4096 Point FFT,
Input Frequency = 375kHz
FREQUENCY (kHz)
0
A
100
200
300
400
LT1409 F02b
0
–20
–40
–60
–80
–100
–120
50
150
250
350
f
SAMPLE
= 800kHz
f
= 375kHz
SFDR = 89dB
SINAD = 72.5dB
Figure 2a. LTC1409 Nonaveraged, 4096 Point FFT,
Input Frequency = 100kHz
FREQUENCY (kHz)
0
A
100
200
300
400
LT1409 F02a
0
–20
–40
–60
–80
–100
–120
50
150
250
350
f
SAMPLE
= 800kHz
f
IN
SFDR = 89.1dB
SINAD = 73.1dB
相關(guān)PDF資料
PDF描述
LTC1412 12-Bit, 3Msps, Sampling A/D Converter
LTC1412C 12-Bit, 3Msps, Sampling A/D Converter
LTC1412CG 12-Bit, 3Msps, Sampling A/D Converter
LTC1412I 12-Bit, 3Msps, Sampling A/D Converter
LTC1412IG 12-Bit, 3Msps, Sampling A/D Converter
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LTC1409CG 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率(每秒):300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數(shù)目和類型:1 個單端,單極;1 個單端,雙極
LTC1409CG#PBF 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率(每秒):300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數(shù)目和類型:1 個單端,單極;1 個單端,雙極
LTC1409CG#TR 功能描述:IC ADC 12BIT 800KSPS SMPL 28SSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率(每秒):300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數(shù)目和類型:1 個單端,單極;1 個單端,雙極
LTC1409CG#TRPBF 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率(每秒):300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數(shù)目和類型:1 個單端,單極;1 個單端,雙極
LTC1409CSW 功能描述:IC A/D CONV 12BIT SAMPLNG 28SOIC RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率(每秒):300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數(shù)目和類型:1 個單端,單極;1 個單端,雙極